07 December 2010

Song of the day: "It's De-lovely" by Cole Porter

I always feel like belting out this song in a hallway.
I feel the sudden urge to sing
The kind of ditty that invokes the spring
So, control your desire to curse
While I crucify the verse
This verse you've started seems to me
The "Tin Pan-tithesis" of melody
So to spare you all the pain
I'll skip the darn thing and sing the refrain

Mi-mi-mi-mi, re-re-re-re, do-so-mi-do-la-si

The night is young, the skies are clear
So if you wanna go walkin', dear
It's delightful, it's delicious, it's de-lovely

I understand the reason why
You're sentimental, 'cause so am I
It's delightful, it's delicious, it's de-lovely

You can tell at a glance what a swell night this is for romance
You can hear, dear Mother Nature murmuring low, "Let yourself go"

So please be sweet, my chickadee
And when I kiss ya, just say to me
"It's delightful, it's delicious, it's delectable, it's delirious,
It's dilemma, it's de-limit, it's deluxe, it's de-lovely"

Time marches on and soon it´s plain
You´ve won my heart and I lost my brain
It´s delightful, it´s delicious, it´s de-lovely

Life seems so sweet that we decide
It´s in the bag to get unified
It´s delightful, it´s delicious, it´s de-lovely

See the crowd in that church
See the proud parson plopped on his perch
Get the sweet beat of that organ sealing our doom
Here goes the groom – boom!

How they cheer and how they smile
As we go galloping down the aisle
It´s divine, dear, it´s de-vene, dear, it´s de-wunderbar, it´s de-victory
It´s de-velop, it´s de-vinner, it´s de-voix, it´s de-lovely

The night is tired and so we take
The few hours off to eat wedding cake
It´s delightful, it´s delicious, it´s de-lovely

It feels so fine to be a bride
And how´s the groom while he´s slightly fried
It´s divineful, it´s delicious, it´s de-lovely

To the pop of champagne, off we hop in our plush little plane
´Til a bright light through the darkness cosily calls, "Niagara Falls"

Well, my love, our day´s complete
What a beautiful bridal suite
It´s de-reamy, it´s de-rousy, it´s de-reverie, it´s de-rhapsodie
It´s de-regal, it´s de-royal, it´s de-ritz, it´s de-lovely

We settle down as man and wife
To solve the riddle called married life
It´s delightful, it´s delicious, it´s de-lovely

06 December 2010

Song of the day: "Experiment" by Cole Porter

Finally, a song loosely about science written by a real songwriter, and not just any songwriter... one of the greatest American songwriters in history, Cole Porter! (If you watch the movie "It's Delovely," you might guess what the characters think the song is about.) My PhD advisor really likes this song.
Before you leave these portals,
to meet less fortunate mortals,
there's just one final message I would give to you.

You all have learned reliance,
on the sacred teachings of science.
So I hope through life you never will decline,
in spite of Philistine defiance.
Do what all good scientists do.

Experiment.
Make it your motto day and night.

Experiment.
And it will lead you to the light.

The apple on the top of the tree
is never too high to achieve.
So take an example from Eve,
experiment.

Be curious,
though interfering friends may frown.

Get furious,
at each attempt to hold you down.

If this advice you always employ,
the future can offer you infinite joy
and merriment.

Experiment,
and you'll see.

28 November 2010

How to do theoretical physics

I talked to a few of my colleagues about what to do when you are stuck. Here is a compilation of their suggestions.

Every theoretical physics PhD student reaches a point where mindless cranking and/or doing what their advisor tells them to do doesn't work anymore. This is a hump that the student must learn to get over. Typically the advisor doesn't know how to solve the problem either. If the advisor sat down for a week and thought about it, he/she could probably solve it, but of course, that's not what happens. Either the student solves it or the project is abandoned. Smetimes the student shows the advisor why the project is too hard.

If you are stuck:
  • Read the literature. Work out all the equations in the papers, and keep your work in a notebook.
  • Talk to lots of people. Be aggressive. It is especially helpful to talk to other students because they are at your level.
  • Figure out why you are stuck. If you quit the project, as least you know why. Sometimes you go around in circles because you don't even know why you are stuck.
Sometimes, there's no problem to solve, because it's been solved already and only a very serious publication search recovers it. Sometimes, it's very hard to find the paper where your problem was solved because many years ago, people used different language. One way to avoid this is to find some people who are experts on the type of problem you're working on, and ask them. This could be tricky, because you don't want them to steal it from you, but if you do it in an advanced stage it would probably won't happen.

A good theoretical physics PhD advisor sees his/her students multiple times during the week. Some advisors likes to pop into their student/postdoc's office and provide "moral support". If your advisor doesn't have time, it's a good idea to email him/her to talk about the project between meetings.

You shouldn't be spending all your time hammering away at one problem. Classes are over, so you should spend time talking to other people and learning about other things. There is nothing to feel guilty about. This is why you are in academia!

For the PhD student, there should be a balance of what they are good at and not good at. If a student is naturally good at numerics, he/she should do some analytical work and vice versa if the student is good at analytical work.

Remember: theoretical physics is hard!! The purpose of theoretical physics PhD is to prove that you can do theory research. Unfortunately, not everyone can pass this "test."

27 November 2010

Essential skills for a scientist

I was having a conversation with someone who wasn't sure what he wanted to study in physics graduate school. He was worried that if he chose one field, it would be very hard to make progress, but it would be important work, whereas if he chose another field, it would be easier to make fast progress, but the work might not be so fundamental.

I wasn't sure what to say, so I advised him to take a different perspective:

"Another way you could make a choice is to think about what skills you want to acquire. You want to have the skills you need when the exciting development comes along, so that you can jump into it right away."

Wolfgang Ketterle, an atomic physicist and 2001 Nobel laureate, himself said that skills are important.
Changing fields was a crucial experience for me. Amazed to see how much of what I had learnt before could be applied within the new field, I realized that general skills are much more important than specific knowledge. I thought it would take a long time before I became productive in my new environment, but within months, graduate students who had been working in this area for much longer came and sought my advice and leadership. This experience gave me the self-confidence to venture into new areas, and provided the impetus for my later decision to come to the United States and start once again in a new field.
(Quoted from the Nobel Prize website autobiography)

The question is, what are the important skills for a scientist to learn? I can think of a few:
  • Asking important questions and picking good research problems, i.e. ones that are solvable and interesting.
  • Understanding the big picture and being able to pick out what is essential and interesting from a mess of details.
  • Turning a relatively vague and abstract research question into a concrete calculation or an observable quantity that can be measured in an experiment.
  • Writing (papers and grants)
  • Speaking
  • Managing and training (teaching) students
  • Collaboration skills
  • Life balance and project management
  • Programming skills
  • Math skills
In addition, for an experimentalist in physical science, it is also important to know some signal processing. (My sister contributed a few items on the list.)

26 November 2010

Arcade gaming at home

I was playing Metal Slug on my Nintendo DS Lite the other day and my hands were dying from so much button pressing. I realized that what I really need is an arcade style joystick. Arcade style games aren't really made anymore, so I could install MAME emulation software on my PC to play retro games like 1942, Gauntlet, Street Fighter II, and Samurai Showdown. A good resource for anything related to building your own MAME arcade box is MAMEWorld. I found some cool stuff like playing Mahjong in MAME and even light guns for your Time Crisis fix!

I had no idea there are so much information about different types of joysticks and buttons. slagcoin has an extensive guide here. Apparently, there are three major joystick types: Happ (US), Sanwa (Japan), and Seimitsu (Japan). It's much easier to get high quality arcade parts from Japan because the arcade games are still popular there. Americans don't really play arcade games anymore. Many people buy parts and mod their own custom joysticks. That sounds like fun, but I'd like to play with some of the off-the-shelf stuff first so I can get a feel for what I like. Eventually, I'd like to do a complete arcade box build project as described in MaximumPC's article "How to Build a Kick-Ass MAME Arcade Cabinet from an Old PC."

There are few recommended off-the-shelf manufacturers.
  • Hori is the biggest game controller manufacturer and has a high quality Real Arcade Pro line.
  • MadCatz makes a Street Fighter IV FightStick Tournament Edition for PS3 and XBox 360.
  • X-Arcade makes US style arcade joysticks. They are lower quality than Hori or MadCatz but they are easy to mod and the PC board is supposedly 100% compatible with MAME.
After some cursory research, these joysticks seem good for a MAME setup:
  • Hori Real Arcade Pro VX-SA for Xbox 360. A top-of-the-line model which uses all real arcade parts and layout.
  • Hori Real Arcade Pro EX-SE for XBox 360. Another top-of-the-line model which uses all real arcade parts. It's unusual in that it uses Seimitsu parts, rather than Sanwa parts. All the other Hori and MadCatz joysticks are Sanwa.
  • X-Arcade Solo Joystick. A decent joystick but kind of pricey for the parts. I would get this one for doing some modding.
There are Hori sticks that are 1/3 cheaper, but they don't use authentic arcade buttons and the whole point was not to do any modding. I looked into MadCatz joysticks, but there wasn't much feedback on using them successfully for MAME emulation.

06 November 2010

Quote of the day: Getting back to who you were

In the episode "False Labor" from the TV series Caprica, Daniel Graystone has a conversation with Joseph Adama.
Daniel: It's like every decision I've made since the bombing has been a wrong turn. By now I've made so many of them I'm not sure I even know how to get back.

Joseph: Get back to where?

Daniel: To who I was, or who I thought I was.

Joseph: You can't do that alone. You need somebody. You need someone who can see the man you were inside the man you've become and forgive you.

10 October 2010

What I've learned

  1. Physics should be fun, like a video game. When I started doing physics, I thought it was a religious calling and that physics was all about doing important things. Looking back, I realize that I invented the idea of a religious calling because I was afraid of my parents disapproving of me doing physics. I went to an elite college where the professors were all super-competitive and serious about science. My motivation for doing physics was horribly warped. A friend of mine told me that when she was excited about research, she would work enthusiastically all night. She said, "It's like playing a video game."
  2. Collaborate with a good friend. Science is so much more fun if you can hang out with your friends and do research at the same time! By friend, I mean someone of your level, not your advisor. When I came to grad school, I wasn't used to working with people my age. I had only worked with professors and senior postdocs. Relationships with senior people tend to be very formal. If you want to grow as a scientist, you need to have some freewheeling discussions where anything goes and no one feels embarrassed about anything.
  3. If you can, find a friend of similar cultural background and gender. This is extremely important if you are a minority. Your cultural majority friends may be the most well-meaning people in the world, but they can't see your whole perspective, only a part of it. It took me a long time to learn this, because I had a very strong ideal that everyone should be culturally neutral, gender neutral, and age neutral. I used to look down on the "women in science" meetings because I thought "these women are bunch of wimps, can't they toughen up?" (The other reason I disliked "women in science" meetings was because the majority of the women were of a different culture from me. So I was a minority within a minority.) The unfortunate reality of the world is that it is much easier for women to be close friends with other women. Similarly, it is much easier for people of the same cultural background to be friends. I was on a hockey team where no matter how much I tried, I never belonged. My teammates were women, but we didn't have anything else in common: different age, different education, different cultural background. Sometimes, a good commonality to bond over is simply sharing the experience of being a minority.
  4. Don't work through deep depression. It's true that when something bad happens, you should keep going to work and keeping up the routine. But don't do this for deep depression. It's the equivalent of trying to run a 10K race on a broken leg. You only make things worse. Not only do you fail to accomplish anything, you will end up destroying your confidence.
  5. When you are in trouble, make sure you talk to people who can *actually* help you. These seems kind of obvious, but when you are in a panic, you usually go to whoever you feel most comfortable with. That person may not be someone who can actually help you. If you are having problems in the workplace, you need to talk to people at your current workplace, not your old workplace. If you are having problems with family, you need to talk to people who know your family well or have the same cultural background as your family.
  6. If you are have a multi-cultural heritage and/or unconventional upbringing, life is even more confusing. My nationality and ethnic background are very different. This is a classic American problem. In addition, I have a gender related problem (hard to explain). My mom was not a good role model for me, so I adopted my dad as a role model and tried to imitate him. I feel uncomfortable around conventional women, but I don't quite fit in with the boys either.
  7. Lay down your burdens. Bad things happen to everyone, but we have to let go of the past and forgive people. I think I always knew this lesson pretty well, but I mention it for completeness.
[Additional note: One of my friends said my post made me sound biased towards certain types of people. I don't want to make it sound like I can only be friends with women or Asians. If I see a Hispanic male walking down the street, I don't think to myself, "Well! There is no way I can be friends with that guy." I strive to be gender-blind, race-blind, orientation-blind, age-neutral, etc. I simply notice that in hindsight, among the friends I gravitate towards most, we seem to have some strong common connection. It's almost possible that I went through a phase where I found it hard to fit in and decided out of bitterness to construct a theory to explain my troubles.]

15 September 2010

Flesh may freeze and stick to cold surfaces

This is a real figure in the Oxford dilution refrigerator manual.  Similarly, don't stick your tongue on cold surfaces.

14 September 2010

The zero Gmail inbox for minimizing distractions

In a somewhat old (but still good!) post, Cal Newport explains how to mark all your incoming messages to Gmail as "read."  I also take the additional step of moving the messages to another label called "process." 

So now I never see anything in my Gmail inbox, which is great for minimizing distractions.  I can still go into Gmail and write messages, but without getting sidetracked by new messages in my inbox.  Having a "zero" inbox means that I'm not tempted to check new messages.  Now I can really stick to only checking my personal email once a day.  I wait until the end of the day to look at my "process" label and respond to the messages then.

I restrict my Gmail account to personal mail, but I think this method might also be helpful to people who receive work mail.

Here's how to set up the filter.
  1. Go to the upper righthand corner of your Gmail screen and click on "Settings".
  2. Click on the tab "Filters".
  3. Towards the bottom of the screen, click on "Create new filter".
  4. In the "From:" field, type hyphen followed by your Gmail address, for example, "-me@gmail.com". This will prevent Gmail from marking your sent emails with the new label we are about to create. So any mail sent to me@gmail.com will not be affected and go to your Inbox normally. You can include several emails, for example, in the "From:" field, type "-me@gmail.com -mom@gmail.com -dad@gmail.com".
  5. Leave all the other fields blank and click on "Next Step".
  6. Gmail asks you to choose some actions. Select the following: "Skip the Inbox (Archive It)", "Mark as read", and "Apply the label:". For the "Apply the label" box, click on the drop-down box and select "New label". Enter a new label and click "OK". I called mine "process".
  7. Click "Update Filter" and you are done.
Instead of going to your inbox, now you go to the "process" (or whatever you called it) label to see your new mail. You can assign labels or delete messages as you normally due. When you are done processing a message, simply remove the "process" label. You can use the shortcut "Y" or click on 'Remove label "process".'

The excluded email addresses ("me@gmail.com" in this example) will not be affected and mail from this addresses are delivered to your Inbox. So you can include important addresses in the excluded list, for instance: "mom@gmail.com". I know, for sure, that a list of hyphened addresses works, e.g. "-me@gmail.com -mom@gmail.com -dad@gmail.com". I have heard reports that using something fancier like wildcards and Boolean operators has problems.

11 September 2010

Some interesting ideas summarized as quotes

“People always ask, ‘What is your greatest failure?’ I always have the same answer – We’re working on it right now, it’s gonna be awesome!” - Jim Coudal

"The key to success is to be cheerful in the face of constant failure."  - my take on failure

"Hara Hachi Bu.  (腹八分)" - a Okinwana saying which means you should eat until you are 80% full (not sure if my translation into Japanese is correct)

There is also some kind of Japanese saying that goes "made stupid by peace."  I'm not sure if this is really a Japanese saying, so correct me if I'm wrong.  The idea is that the peace and comfort we experience in first world countries makes us lazy and complacent.

04 September 2010

New top games list

Here is a new list of my favorite video games (from this decade).  Most of these games are for the Nintendo DS and Gamecube.  I've never owned an Xbox or Playstation console, so I wasn't able to play games on those systems.  The old list of top games was from the 1990s decade.
  1. Paper Mario: Thousand Year Door (Gamecube)
  2. Prince of Persia trilogy (The Sands of Time, Warrior Within, The Two Thrones) (console/PC)
  3. Chrono Trigger (SNES/DS)
  4. Phoenix Wright series (GBA/DS)
  5. The Legend of Zelda: Twilight Princess (Gamecube/Wii)
  6. Mario Kart: Double Dash (Gamecube)
  7. Dragon Quest V: Hand of the Heavenly Bride (SNES/PS2/DS)
  8. Mario Superstar Baseball (Gamecube)
  9. The Legend of Zelda: Phantom Hourglass (DS)
  10. Tales of Monkey Island (PC/Wii)
  11. Dragon Quest IX: Sentinels of the Starry Skies (DS)
  12. Paper Mario (N64)
  13. Mario Power Tennis (Gamecube/Wii)
  14. Super Smash Brothers Melee / Brawl (Gamecube/Wii)
  15. Ikaruga (Gamecube)
  16. flOw (PC)
  17. Professor Layton and the Curious Village (DS)
  18. Space Invaders Extreme (DS)
  19. Sid Meier's Civilization Revolution (DS)
  20. Age of Empires: Age of Kings (DS)
  21. Animal Crossing (N64/Gamecube)
  22. Cooking Mama (DS)
  23. Super Mario Strikers (Gamecube)

22 August 2010

Tabletop cameras for travel

The first time I went abroad with my dSLR camera, I brough a tiny tabletop tripod to Asia with me. It was a Manfrotto tripod (model 709B) with extension column. Tripods are the bane of photography. They are heavy and big. I didn't want to lug around a regular tripod, hence I brought the tabletop tripod.

It was actually much more useful that you would have thought. The photo below was taken with that tripod. I put the camera and tripod on the railing of the bridge.



Now I would like to emphasize that tabletop tripods are not a magic solution. They won't beat a regular tripod. Certainly, they are much less stable.  To use a tabletop tripod, you have to have elevated surfaces to put it on. You can get lucky and find spots like that in urban places, but I'm not sure if you will be so lucky in less developed areas. Also, if you are shooting outside on the mountain etc, you will need something that can stand on an uneven surface. Some people recommend the Gorrilapod.

In any case, bringing a tabletop tripod is a bit of a gamble. Some experienced photographers use the tabletop tripod as a "chest" pod. They put the tripod on their chest to stabilize the camera. I've never tried it but one of the guys at B&H likes doing it.

21 August 2010

Comments on picking a camera bag

Picking a camera bag is a bit like picking a purse. There is one for every occasion and you probably need more than one. The main categories of camera bags are backpack, sling bag, toploading.

Backpacks
I prefer camera backpacks (ex: I have Lowepro Fastpack 250 and Kata Sensitivity V) because it's easy to access the camera and I don't kill my back by using a shoulder strap. But it's extra luggage if you are traveling. I like camera backpacks with a lower camera compartment and an upper compartment where I can put other stuff. I also like the backpack to have a laptop compartment. Not that I would want to carry a laptop while I'm shooting, but it's handy if I travel on an airplane or if I want to put a folder with paper in it (the other compartments are too small for an 8.5" x 11" sheet of paper). I'm not a fan of the one huge compartment that you fill with camera equipment and lenses. But lots of pros use this type of bag.

Sling bags
Sling bags (ex: Lowepro Slingshot) are smaller than backpacks. They are called "sling" because they give you the option of quick access to your camera. Some backpacks may claim to give you quick access to your camera, but sling bags are much better for this feature. However, they only have a single shoulder strap, unlike a backpack which evenly distributes weight.

Toploading bags
Toploading bags are similar to sling bags (easy access to camera and one shoulder strap)... except toploading bags are only meant to carry the camera with one lens attached. There's no room for an extra lens. If you're traveling and can't carry an extra backpack, you could put your camera in a toploading bag and put that inside of a large backpack.

Combo bags
Kata has a new bag out called the Sling Backpack which supposedly can be used as both a backpack and a sling bag.

Other types of bags
Shoulder bags are kind of like really bulky messenger bags. I don't see why anyone would buy these. They aren't great for quick access to your camera. Also, there's the temptation to put too much in a shoulder bag and you will end up destroying your back. Beltpacks are for carrying your camera on your belt. It's an interesting idea, but I've never tried a beltpack. One worry I have is that the beltpack will get in your way or whack into people.

I should mention a few considerations in choosing a camera bag. One issue people often bring up is that if your bag looks too much like a camera bag, it is more likely to be stolen. My Kata Sensitivity V bag looks nothing like a camera bag and in that sense it's great. It also looks very stylish and I get compliments. I napped in a Starbucks once with my Kata bag at my feet and it wasn't stolen. Crumpler bags are also known for being very stylish and not looking like camera bags.

Another issue is whether the bag will fit under your airline seat. Never put a dSLR in the overhead compartment (my camera lens was damaged and it cost $200 to repair).

Also, I found that if my camera bag was too bulky, I was constantly knocking into people with it. A camera bag with a slim profile will help avoid this problem.

The three big camera bag companies are Lowepro, Tamrac, and Kata. Lowepro and Kata include a rain cover with some of their products, which is nice. However, you can always buy your own rain cover. Kata makes the most stylish and innovative products. You can't go wrong with any of these companies.

20 August 2010

Essential accessories for a digital SLR camera

  • Camera bag/backpack -This is the toughest item to shop for. Professional photographers have many bags for different situations. A discussion of camera bags deserves its own post.
  • Manual - Always bring your manual. You never know when you need to look up something. Keep your manual in a good ziplock bag, so it doesn't get wet.
  • UV filter - To protect your lens in rough environments
  • Lens cleaning kit - A kit typically includes a blower brush, lens tissues, and a bottle of lens cleaning fluid. I also like getting packs of lens wipes for convenience. A lens wipe is a lens tissue already coated with lens cleaning fluid and sealed inside a packet. Zeiss makes some nice lens wipes.
  • Waterproof pack cover - So the camera inside your pack doesn't get wet. For example, the Sea-to-Summit pack covers.
  • Extra battery - Never go without a backup battery. This is also useful for cold weather situations. You can keep the backup battery near your warm body and swap it with the battery inside your camera. Keep swapping back and forth whenever the battery in the camera gets too cold to operate.
  • Extra memory cards - I recommend 4 GB for 10-12 megapixel cameras and 8 GB for higher megapixel cameras. The speed of the cards should match the transfer speed of your camera. Cameras with higher frame rate will need faster cards. The idea is that you spread out the risk. Instead of getting one huge memory card (say 16 or 32 GB), you get 3 medium sized (say 4 or 8 GB) memory cards. If you lose one or it gets corrupted, you're still OK. You only lost the images on that one card.

  • Backup camera - If something goes wrong with your main dSLR camera, you need a backup. In fact, this is what separates a pro photographer from someone who just shoots as a hobby. A pro photographer has to have backup equipment because they can't tell their client that they took zero photos due to equipment problems. The backup camera doesn't have to be another dSLR. You can use a point-and-shoot camera. A good thing about point-and-shoot cameras is that they are great for macro because of their inherently short focal lengths. It's difficult to shoot macro on a dSLR without a specialized macro lens.
  • (optional but important) Tripod/monopod - If you want to do any macro or long-exposure work, you will need a tripod. You can get by without a tripod if you focus on event shooting, but eventually you will want a tripod. Monopods are useful when tripods aren't allowed or if you need some freedom for movement.
  • (optional but important) Flash - Important for shooting inside dark rooms like at a party. You want a flash that can be tilted at angles. This is useful for bouncing the flash off walls and ceilngs. You can use the built-in flash on your camera, but it's not very good. A small flash is fine. Examples are the Nikon SB-400 Speedlight and the Canon Speedlite 270EX. If you have the money and don't mind the weight, you could get a big, pro-level flash.
  • (optional but important) Better camera strap - I didn't like the strap that came with my camera so I got the Op-tech Pro strap. It was much more comfortable for carrying heavy lenses around my neck.

19 August 2010

Online resources for learning about digital SLR photography

I'm no expert on all the resources you can find on the internet, but here are some of my personal favorites.
  • dpreview - Trustworthy and extremely thorough reviews of digital SLR cameras and lenses. The articles can be quite technical.
  • B&H Event Space videos - B&H (arguably America's best camera store) holds dozens of seminars each month about photography. They are great to attend in person, if you can manage to get to New York. For the rest of us, fortunately, some of the seminars have been taped and posted online. If you watched 20 B&H seminars, you would learn so much.
  • Digital Photography School - Lots of nice articles about almost any topic in photography. Most articles are aimed at beginning and intermediate photographers.
If you are a beginning photographer, I would avoid Ken Rockwell. He is a very opinionated guy and I don't agree with everything he says. Novices won't be able to tell between facts and Rockwell's opinions.

18 August 2010

How to get a feel for the controls on a camera

The most important aspect of a camera is whether you are comfortable holding it and changing its settings. When buying a camera with manual controls (whether it is film or digital, point-and-shoot or SLR), you should go to a store and try it out.

At store, this is what you should try:
  1. Go into aperture mode and try changing the aperture.
  2. Try changing the ISO.
  3. Try changing the autofocus mode.
  4. Try changing the white balance mode.
  5. Try changing the exposure compensation (+/-).
  6. Go into manual mode and try changing aperture and shutter speed.
Do you have a good grip on the camera when you are shooting and when you are changing the settings? These are all important considerations because if you're not physically comfortable with the camera, you shouldn't buy it.

15 August 2010

Examples of exposure metering fooled

Here are some photos to illustrate how the camera metering system can be fooled by extremely light or dark scenes.  The camera assumes that the scene is a medium gray (the meter works in grayscale not color) and tries to exposure the scene so that the medium gray is properly exposed.  In these photos, I determined proper exposure by using the camera's evaluative (or matrix) metering setting.  One stop underexposed is equivalent to -1 in exposure compensation.  One stop overexposed is equivalent to +1 in exposure compensation. You can click on the photo to enlarge it.

A brick wall is a medium dark color, so the camera meter gets the right exposure.  As we can see below, the "properly exposed" shot looks best.


One stop underexposed




Properly exposed




One stop overexposed


A white scene (for example, snow or ice) will cause the camera to underexpose the scene.  The camera thinks the white is too bright and tries to reduce exposure.  If you encounter a very light scene, you should set your exposure compensation to be positive.  As we can see below, the "overexposed" shot looks best.  (In this case, the camera metering didn't quite do what I expected.  The best exposure might be in between the "properly exposed" and "overexposed" shots.)



One stop underexposed





Properly exposed





One stop overexposed


A very dark scene will cause the camera to overexpose the scene.  The camera thinks that the scene is too dark and tries to increase exposure.  If you encounter a very dark scene, you should set your exposure compensation to be negative.  As we can see below, the "underexposed" shot looks best.



One stop underexposed





Properly exposed





One stop overexposed

14 August 2010

The effect of aperture on depth-of-field

The larger the aperture (smaller f-stop), the smaller the depth-of-field.

Here's a series of bike photos (click on the photo to see larger size):

f/2.8 @ 1/2000 sec


f/22 @ 1/40 sec


Another example with a fence:

f/2.8 @ 1/1600 sec


f/8 @ 1/200 sec


f/16 @ 1/40 sec

13 August 2010

Entry level vs semi-professional digital SLR cameras

Grip
Entry level dSLR cameras are less sophisticated and have no weather sealing, so they have a smaller form factor. The semi-pro cameras will be larger and bulkier. If you have large hands, you may find it hard to grip an entry level camera. If you have very small hands, you may find it hard to grip a semi-pro camera.

Controls
Most functions on an entry level camera have to be changed on the LCD screen, which means that you have to take your eye off the viewfinder. You have to hold the camera way from you and scroll through menus to adjust settings. This may cause you to miss some shots. With semi-pro cameras, you can change almost all the important settings without taking your eye off the viewfinder. Most of the important settings have a dedicated button (ISO, white balance, AF, etc). Dedicated buttons and the ability to change settings quickly is very important to event photographers and journalists.

Autofocus and frame rate
The autofocus systems are better and the frame rates are higher on semi-pro dSLR cameras compared to entry-level ones. You get what you pay for. If you shoot sports or wildlife, you are better off with a semi-pro camera.

Weather sealing
Semi-pro dSLR cameras have some weather-sealing. Some even have professional grade weather sealing. The Canon 7D supposedly survived a trip to Antarctica. Entry level dSLR cameras don't have weather sealing. If you are using an entry level camera in rough conditions, I would recommend bringing a weather cover for the camera and lens.

Weight
Entry level cameras are lighter than semi-pro cameras because they are made of plastic. Semi-pro cameras have a metal frame which is more durable.

25 July 2010

Song of the day: "Danny Boy" by Frederick Weatherly

A beautiful song to sing, but not the easiest to sing. I think this is a "benchmark" song for tenors.
Oh Danny boy, the pipes, the pipes are calling
From glen to glen, and down the mountain side
The summer's gone, and all the flowers are dying
'Tis you, 'tis you must go and I must bide.

But come ye back when summer's in the meadow
Or when the valley's hushed and white with snow
'Tis I'll be here in sunshine or in shadow
Oh Danny boy, oh Danny boy, I love you so.

And if you come, when all the flowers are dying
And I am dead, as dead I well may be
You'll come and find the place where I am lying
And kneel and say an "Ave" there for me.

And I shall hear, tho' soft you tread above me
And all my dreams will warm and sweeter be
If you'll not fail to tell me that you love me
I'll simply sleep in peace until you come to me.

25 May 2010

How to consistently white balance photos in Lightroom

I have no professional training in graphic design or color management, but here is a Lightroom trick I use when I have a bunch of photos I want to consistently white balance.
  1. Get your photos into grid mode (whether this is by selecting a collection/folder or filtering a collection/folder).
  2. Pick one photo as your reference.
  3. White balance that photo the best you can. Sometimes I like to open up the photo in Photoshop and use Adjustments -> Variations to help me with the white balancing.
  4. After you are done, go back to grid mode, select the reference photo.
  5. Right-click on the photo and select "Lock to second window."
  6. Select the first photo in your grid, open it in the Develop module (press "D"), and press "Y" to open the photo in split view. You want the split view where there are two variations of the same photo side-by-side, not the one where you have one photo split down the middle. If you're in the wrong split view, press "SHIFT-Y" to change views.
  7. Open up the second window by clicking on the rectangle with "2" in it, at the bottom lefthand corner of the screen or pressing F11.
  8. This is your reference photo. Move the second window to cover up the photo on the left.
  9. Now you can white balance the current photo against reference photo. Use the left and right arrow keys to cycle through the entire set of photos in the grid.

19 May 2010

HD dSLR video vs traditional 35mm film

HD dSLR video is all the rage nowadays. But I'm a still shooter and know very little about "motion." I should discuss some terminology and technical issues that relate to motion pictures, but that we don't worry about in still photography. First, video refers to shooting without film (no rolls of film that need to be processed in a chemical lab. Second, you do not use auto-focus for shooting motion pictures. Hollywood studios employ "focus-pullers." Their job is to manually focus the camera at all times, so that the appropriate scenery/actor is in focus. People and things move around, so this is not an easy job.

I learned about the differences between HD dSLR and 35mm film from two sources: Ken Rockwell who used to work in Hollywood before focusing on digital photography and an interview with Greg Yaitanes who recently directed the season finale of House. The episode was filmed entirely with the Canon 5D Mark II. They're coming from a professional, Hollywood studio perspective, but I think much of the discussion is still relevant to amateur filmmakers.

Pros of HD dSLR
  • No film and processing to pay for (that same advantage that digital still cameras have over film still cameras) - this will save you tons of money. According to Ken Rockwell, an hour of film costs a Hollywood studio $10,000 - for the film itself and all the processing.
  • Since HD dSLR is already digital, you can take advantage of an all-digital workflow. This can save you lots of time and money since you can do all your post-production with your own team of people, in-house. The same advantage that digital still cameras have over still film cameras.
  • You can shoot at ISO 1600+ and do amazing low-light video, which is not possible on film.
  • The dSLR is tiny compared to the 35mm film camera, so you can record video in very tight spaces and not have to remove walls in your set in order to film from different angles
  • There are tons of fast lenses available already for still cameras. You can shoot with an f/1.2 lens and get amazingly shallow depth-of-field. Or better yet, use a macro lens! According to Greg Yaitanes, they shot the House episode mostly with the 50mm f/1.2 and 85mm f/1.2 Canon lenses, and they also used the 24-70mm f/2.8, 70-200mm f/2.8, and 100mm macro lenses somewhat. Yaitanes claimed that he could get depth-of-field on the Canon 5D Mark II that was one quarter smaller than film.
  • Or heck, imagine shooting video with a tilt-shift lens or fisheye! So many creative possibilities open up when you can use still camera lenses.
  • The dSLR full frame sensor (24mm x 36mm) is larger than the 35mm film frame (approximately 18mm by 22mm). APS-c sensors are comparable in size to film (approximately 16mm x 23mm). So you'll always get shallower depth-of-field with full frame dSLR sensors. This is the reason why Greg Yaitanes chose to use the full-frame Canon 5D Mark II over the APS-c Canon 7D and APS-H Canon 1D Mark IV.
Pros of 35mm film
  • In general (at "normal" ISOs), film simply has better image quality than HD dSLR video. This is the big issue. Film has a much better response to highlights whereas CMOS/CCD sensors blow out highlights very easily. However, if you are very good at lighting, you can probably use HD dSLR video and get around it somewhat. As Ken Rockwell says, you cannot do HDR with HD dSLR video. At least not right now.
  • Manual focus on HD dSLRs is very difficult. Since the exciting part of shooting with HD dSLR is the potential for super shallow depth-of-field, that makes focusing even more difficult. But this should change as camera manufacturers get feedback from film makers and they improve the technology. Zeiss recently came out with fast, manual-focus prime lenses, designed specifically for HD dSLR video.
  • Hollywood studios have been working with film forever, so they know how to use it. HD dSLR video is a new technology and film crews have to learn how to use it.

12 May 2010

What I've learned about making photobooks

I recently completed by first photobook. I used Adoramapix's online Flash software and had the book printed by Adorama, but my discussion should apply to making any photobook.

I wasted a lot of time because I would process a photo, put it into the photobook, and then move on to the next photo and do the same. Then I would realize that I didn't want to use that photo or that it was cropped wrong or that there was a color cast. Then I'd have to go back and fix it.

You should start by cropping and throwing the photos into the book making software, without any further corrections. Then move the photos around, swap photos in and out. Then wait a week or two and come back to it. Spend some time re-arranging the photos, swapping photos, etc. When you are reasonably sure of your design and layout, THEN start playing with color balance and curves. If you have a group of photos taken in the same lighting situation, record and use the same color settings for all of them. Be especially careful to make colors consistent for photos on the same spread. From your rough layout, you should know what size your photos need to be for 300 dpi. Crop your photos to exactly 300 dpi or whatever resolution the printer claims to use. Otherwise, you are at the mercy of the booking software for resizing your photos.

Be careful what font you use. Frankly, most people, including myself, have no taste in typography. What looks good on the screen is usually not good for print. John Paul Caponigro has some advice on good fonts for photobooks.

21 April 2010

Anne Lamott on the frustration and rewards of writing and other creative pursuits

Quotes by Anne Lamott from Bird by Bird
Hope begins in the dark, the stubborn hope that if you just show up and try to do the right thing, the dawn will come. You wait and watch and work: you don't give up. (pxxiii)

All I know is that the process is pretty much the same for everyone I know. The good news is that some days it feels like you just have to keep getting out of your own way so that whatever it is that wants to be written can use you to write it. It is a little like when you have something difficult to discuss with someone, and as you go to do it, you hope and pray that the right words will come if only you show up and make a stab at it. (p7-8)

What's real is that if you do your scales every day, if you slowly try harder and harder pieces, if you listen to great musicians play music you love, you'll get better. At times when you're working, you'll sit there feeling hung over and bored, and you may or may not be able to pull yourself up out of it that day. But it is fantasy to think that successful writers do not have these bored, defeated hours, these house of deep insecurity when no one feels as small and jumpy as a water bug. They do. But they also often feel a great sense of amazement that they get to write, and they know that this is what they want to do for the rest of their lives. (p14)

E. L. Doctorow once said that "writing a novel is like driving a car at night. You can see only as far as your headlights, but you can make the whole trip that way." You don't have to see where you're going, you don't have to see your destination or everything you will pass along the way. You just have to see two or three feet ahead of you. (p18)

I also remember a story that I know I've told elsewhere but that over and over helps me to get a grip: thirty years ago my older brother, who was ten years old at the time, was trying to get a report on birds written that he'd had three months to write, which was due the next day. We were out at our family cabin in Bolinas, and he was at the kitchen table close to tears, surrounded by binder paper and pencils and unopened books on birds, immobilized by the hugeness of the task ahead. Then my father sat down beside him, put his arm around my brother's shoulder, and said, "Bird by bird, buddy. Just take it bird by bird."

I tell this story again because it usually makes a dent in the tremendous sense of being overwhelmed that my students experience. Sometimes it actually gives them hope, and hope, as Chesterton said, is the power of being cheerful in circumstances that we know to be desperate. Writing can be pretty desperate endeavor, because it is about some of our deepest needs: our need to be visible, to be heard, our need to make sense of our lives, to wake up and grow and belong. It is no wonder if we sometimes tend to take ourselves perhaps a bit too seriously. (p18-19)

I think that something similar happens with our psychic muscles. They cramp around our wounds -- the pain from our childhood, the losses and disappointments of adulthood, the humiliations suffered in both -- to keep us from getting hurt in the same place again, to keep foreign substances out. So those wounds never have a chance to heal. Perfectionism is one way our muscles cramp. In some cases we don't even know that the wounds and the cramping are there, but both limit us. They keep us moving and writing in tight, worried ways. They keep us standing back or backing away from life, keep us from experiencing life in a naked and immediate way. (p29-30)

If you don't believe in God, it may help to remember this great line of Geneen Roth's: that awareness is learning to keep yourself company. And then learn to be more compassionate company, as if you were somebody you are fond of and wish to encourage. I doubt that you would read a close friend's early efforts and, in his or her presence, roll your eyes and snicker. I doubt that you would pantomime sticking your finger down your throat. I think you might say something along the lines of, "Good for you. WE can work out some of the problems later, but for now, full steam ahead!" (p31)

There's an old Mel Brooks routine, on the flip side of the "2,000-Year-Old Man," where the psychiatrist tells his patient, "Listen to your broccoli, and your broccoli will tell you how to eat it." ... It means, of course, that when you don't know what to do, when you don't know whether your chracter would do this or that, you get quiet and try to hear that still small voice inside. It will tell you what to do. The problem is that so many of us lost access to our broccoli when we were children. When we listened to our intuition when were small and then told the grown-ups what we believed to be true, we were often either corrected, ridiculed, or punished. ... So you may have gotten into the habit of doubting the voice that was telling you quite clearly what was really going on. It is essential that you get it back.

You need your broccoli in order to write well. Otherwise you're going to sit down in the morning and have only your rational mind to guide you. Then, if you're having a bad day, you're going to crash and burn within a half hour. You'll give up, and maybe even get up, which is worse because a lot of us know that if we just sit there long enough, in whatever shape, we may end up being surprised. (p110-111)

If you are not careful, station KFKD [K-Fucked] will play in your head twenty-four hours a day, nonstop, in stereo. Out of the right speaker in your inner ear will come the endless stream of self-aggrandizement, the recitation of one's specialness, or how much more open and gifted and brilliant and knowing and misunderstood and humble one is. Out of the left speaker will be the rap songs of self-loathing, the list of all the things one doesn't do well, of all the mistakes one has made today and over an entire lifetime, the doubt, the assertion that everything that one touches turns to shit, that one doesn't do relationships well, that one is in every way a fraud, incapable of selfless love, that one has no talent or insight, and on and on and on. (p116)

Here is the best true story on giving I know, and it was told by Jack Kornfield of the Spirit Rock Meditation Center in Woodacre. An eight-year-old boy had a younger sister who was dying of leukemia, and he was told that without a blood transfusion she would die. His parents explained to him that his blood was probably compatible with hers, and if so, he could be the blood donor. They asked him if they could test his blood. He said sure. So they did and it was a good match. Then they asked if he would give his sister a pint of blood, that it could be her only chance of living. He said he would have to think about it overnight.

The next day he went to his parents and said he was willing to donate the blood. So they took him to the hospital where he was put on a gurney beside his six-year-old sister. Both of them were hooked up to IVs. A nurse withdrew a pint of blood from the boy, which was then put in the girl's IV. The boy lay on his gurney in silence while the blood dripped into his sister, until the doctor came over to see how he was doing. Then the boy opened his eyes and asked, "How soon until I start to die?"

Sometimes you have to be that innocent to be a writer. Writing takes a combination of sophistication and innocence; it takes conscience, our belief that something is beautiful because it's right. To be great, art has to point somewhere. So if you are no longer familiar with that place of naive conscience, it's hard to see any point in your being a writer. Almost all of my close friends are walking personality disorders, but I know innocence is in them because I can see it in their faces and in their decisions. I can almost promise that this quality is still in you, that you are capable of quiet heroism. (p205)

14 April 2010

Lorne Michaels on life

I've been watching rented DVDs of 30 Rock from Netflix. On Disc 2 of Season 2, there is a bonus feature showing footage from a group interview of the cast and crew by Brian Williams at the Academy of Television Arts & Sciences. I was surprised to learn how much the cast admires their executive producer, Lorne Michaels, who also runs Saturday Night Live.
Brian Williams: Alec Baldwin, same question [of all the things you've done, where does 30 Rock fit]. After all you've accomplished in your career from, gotta throw in Tony Bennett, classic, to Glengarry Glen Ross, the favorite scene of so many people here, this [30 Rock] gives you something else entirely.

Alec Baldwin: I learned from Lorne, that is to say, this is the greatest day of my life, right now, today, here, with all of you, now. This is the greatest day of my life, I'm so happy to be here with all of you, thank you... [cracks up] ... No ... [Alec Baldwin goes on to speak more seriously]

Brian Williams: ... Tina, that brings us circling back to you. I saw that the character, that Alec plays, is absolutely intended to be a mirror image of Lorne. Explain.

Tina Fey: It's not, it's certainly not...

Brian Williams: Misquoted?

Tina Fey: Yeah, of course. It's not entirely Lorne. But there is an element to it that is truncated, you don't get the full sense of it, that is, there is certainly a friendship between the two characters [Liz Lemon and Jack Donaghy] that I would like to believe reflects my friendship with Lorne. And there's, I think, a little bit of a worldview that Jack Donaghy has with like "you should have a great life." "And you should have a great house and you should rise above what you think you can be." And that actually is the part that, I feel, comes from Lorne. And then the more corporate aspects are all from sort of corporate biographies that we've tried to read and fallen asleep.

Brian Williams: Lorne, have you in fact urged people you've worked with to have a "great house"?

Lorne Michaels: Yes, I do.

Brian Williams: It's one of your bedrock principles.

Lorne Michaels: Exactly. I always say get an apartment so when you come home at night, you go "who lives here?.. Someone great must live here. Oh, it's I live here." [Tina Fey is mouthing the words and practically beaming while Lorne Michaels is saying this.] Because you work really really hard.
I like the idea: "today is the greatest day of my life." It's a variation on John Wooden's motto, "Make every day your masterpiece."

Here is my take on Lorne Michael's statements (which should not be attributed to Lorne Michaels since I don't know him at all). You deserve to live a great life, you are a great person, and everything you do should be a reflection of that. Today is the greatest day of your life because it's full of opportunity. You have the entire day to make yourself great and even better. And if you've done things right, you've made your life great and you should enjoy it.

11 April 2010

What is the comedy ethos?

Thanks to Tina Fey and her awesome TV sitcom 30 Rock, I've become interested and even excited about comedy. I was a big fan of Scrubs for the past couple years, but that show focuses on a narrow brand of comedy: outrageous fantasy sequences and slapstick. 30 Rock has much more variety and takes far more risks.

I've been so impressed by Fey's work and reputation that I even gave Saturday Night Live (SNL) a second chance. I prefer longer-form, character-driven comedy, so the sketch comedy of SNL doesn't really appeal to me. But now I can appreciate sketch comedy in the broader context of the comedy ethos.

I may very well be wrong, but this is what I think the comedy ethos is: First, you can do whatever you want as long as you insult everyone/everything equally. In other words, you can insult whoever you like as long as you spare no one. Second, a true professional will do whatever it takes to make the audience laugh, no matter how disgusting/offensive/disturbing/insulting. Sometimes the goal is not to make people laugh in the "haha" sense, but to shock them or make them think about a topic they ignore or avoid.

I now understand the appeal of being a comedy performer. You are allowed to behave in crazy ways that you'd never get away with in proper society.

07 March 2010

Song of the day: "Dream a Little Dream of Me" by Andre, Schwandt, and Kahn

Michael Bublé sings a beautifully smooth version of this song.

Music by Fabian Andre and Wilbur Schwandt
Lyrics by Gus Kahn
Stars shining bright above you, night breezes seem to whisper, "I love you".
Birds singing in the sycamore tree, "Dream a little dream of me".
Say "nighty-night" and kiss me. Just hold me tight and tell me you'll miss me.
While I'm alone and blue as can be, dream a little dream of me.

Stars fading, but I linger on, dear.
Still craving your kiss, I'm longing to linger till dawn, dear.
Just saying this: Sweet dreams till sunbeams find you.
Sweet dreams that leave all worries behind you.
But in your dreams whatever they be, dream a little dream of me.

Stars fading, but I linger on, dear.
Still craving your kiss, I'm longing to linger till dawn, dear.
Just saying this: Sweet dreams till sunbeams find you.
Sweet dreams that leave all worries behind you.
But in your dreams whatever they be, dream a little dream of me.

04 March 2010

Link of the day: Looks, 1/f distribution, myth of meritocracy

First, an old link from months ago that I forgot to post: Your looks and your inbox. OK Cupid, an online dating service, does cool statistical analyses of how your profile affects response rate. One idea to take away is that women are very harsh on men's looks. Ouch.

One of the key ideas in my research is quantum noise. So it's neat to find an article claiming that modern movies have a cut frequency that follows a 1/f distribution.

Finally, via Cal Newport and a few links, I enjoyed the following New York Magazine article on why kindergarten admissions tests are worthless. The single most interesting takeaway message is how unreliable intelligence tests are for 4 year-olds.
I wrote to [University of Iowa psychologist David] Lohman and asked what percentage of 4-year-olds who scored 130 or above would do so again as 17-year-olds. He answered with a careful regression analysis: about 25 percent.

17 February 2010

Link of the day: Luck and choices

I read an interesting psychology article about so-called "luck" (via Lifehacker). A UK psychologist studied "lucky" versus "unlucky" people. I wouldn't call it luck, but rather a good attitude and a positive, optimistic attitude. According to the results of the study, having those things make you more open to new possibilities and opportunities.

Again from Lifehacker, I found this poetic image entitled "When faced with two choices." It reads "When faced with two choices, simply toss a coin. It works not because it settles the question for you. But because in that brief moment when the coin is in the air, you suddenly know what you were hoping for." I interpret this as: if you are having a hard time making a choice, force yourself to make a decision in a split second. Then you'll go with your intuition and feelings.

04 February 2010

Link of the day: Canon 7D + Lensbaby used to shoot Hollywood television

Awesome! I didn't know big-time Hollywood people were using the Canon 7D (+ the Lensbaby!) to shoot television. Read all about it in this post by Philip Bloom. Too bad I can't find the relevant clip from "Dollhouse" but according to the information in the post, I believe it is in the episode "Belonging."

31 January 2010

Thoughts on deliberate practice

Lately I've been intrigued by discussion of deliberate practice. Cal Newport has a nice post explaining what "deliberate practice" really is.

Looking back at life, I can see where I applied deliberate practice. It’s really easy to do deliberate practice with sports since they are so structured and well-defined. I think that’s a good area to start with, to see how it’s done and to gain confidence. That's right: learning a sport is a good way to "practice" deliberate practice. In college, I spent about a year learning skating and hockey so I could make the varsity hockey team. I went to a couple PE classes and then spent as much time as I could at public skate and intramural hockey.

Here are my general thoughts about how to apply deliberate practice. The obvious factor everyone has already mentioned is practice time. (Malcolm Gladwell has popularized the notion that it takes 10,000 hours to become an expert on something.) Then read as much as possible about your subject. That could mean reading books, talking to people who are good at what you want to learn, or watching videos on the internet. Learn good technique and learn good taste (why do people think successful person X in your field is so great?). If you really want to get good fast, move to a place where you can fully immerse yourself in the topic. For example, if you want to become an artist, move to New York. If you want to learn a foreign language, move to that country.

Then refine and tailor the learning technique to yourself. Not all training methods will work for everyone. Find a way to maximize the efficiency of your learning technique. In hockey, professionals don’t practice hours everyday. They practice one hour at maximum intensity, just like a game situation. It is better to practice small amounts of time at high intensity then for long periods at low intensity.

If you want to become decently good at multiple things (as opposed to the 10,000 hour expert), I think it’s best to choose a hard fundamental area of the topic. If you want to become a scientist, physics is a great topic because it forces you to appreciate deep understanding. Physicists find it really easy to jump into other sciences like biology or linguistics. (Disclaimer: I am a physics grad student.) If you want to become a great visual artist, I would pick drawing/painting over photography. I’ve studied bits of both and I can already see that the technical aspects of photography are really easy to pick up. Drawing is much more skill-oriented and really forces you to think hard. There are plenty of self-taught photographers, but that's not really so true of painters.

Deliberate practice can be done in different amounts. Malcolm Gladwell's figure of 10,000 hours is intimidating because it means spending 20 hours a week learning for ten years. Committing ten years of your life isn’t really realistic. What I think one should do is do deliberate practice on one thing for a year at a time and evaluate at the end of the year.

20 January 2010

Being grateful

It is hard to get caught up in negativity. An American society that constantly glorifies a select few and ignores everyone else. The media that seems to think that the only good news is bad news.

One of my professors from college told me that once in a while, he will go to a cafe, sit down for a while, and just write down the things he's grateful for. My sister told me about how she and her friend would email each other every day about what they were grateful for.

My sister and I have been doing the email exchange ourselves for the last couple months. We call it the "gratefulness thread." I like it a lot; a low-key way for me to remember the good and share in my sister's pleasures (small and large).

13 January 2010

Song of the day: "Daddy" by Sammy Kaye

This is a fun but slightly sketchy song. I love Kristin Chenoweth's interpretation of it.
Hey, listen
To my story 'bout a gal named Daisy May
Lazy Daisy May
Her disposition
Is rather sweet, and charming
At times, alarming
So they say

Do do do do do doo doo doo
Do do do do do doo doo doo

She had a man tall, dark, and handsome
Large and strong
To whom she used to sing this song

Hey, Daddy
I want a diamond ring
Bracelets, everything
Daddy
You oughta get the best for me

Hey, Daddy
Gee, won't I look swell in sables
Clothes with Paris labels
Daddy
You oughta get the best for me

Here's an amazing revelation
With a bit of stimulation
I'd be a great sensation
I'd be your inspiration

Daddy
I want a brand new car
Champagne, caviar
Hey, Daddy
You oughta get the best for me

Here's an amazing revelation
With a bit of stimulation
I'd be a great sensation
I'd be your inspiration

Daddy
I want a brand new car
Champagne, caviar
Daddy
You oughta get the best for me
You oughta get the best for me
You oughta get the best for me

09 January 2010

Confessions of a converted lecturer

I watched "Confessions of a converted lecturer", a special talk on science education by Harvard physics professor Eric Mazur. The talk started a little slow, but became very interesting at the half hour mark. Well-worth watching. Here are my notes from the talk.

Prof. Mazur taught the introductory physics course at Harvard. It was mostly aimed at pre-med students, but unlike most pre-med physics classes, it was calculus based. The first year he taught the course, he went to a colleague who had taught it previously and asked him what textbook to use. The colleague said, "Halliday and Resnick", so Mazur assigned that as the text. But now that there was a textbook, what would he say in his lectures? The colleague had mentioned some other books and one of them was out-of-print. So Mazur thought, "Perfect! That's the book I'll use." Mazur would then spend 10 hours preparing each lecture out of this out-of-print book. When he first stated teaching, he thought he was a great teacher because the students did well on the tests and because he got good evaluations. Mazur provided photocopies of his lecture notes for the students and consequently, a few students complained that "Prof. Mazur lectures out of his lecture notes!"

This made Mazur realize that lectures focus on delivery of information. This was certainly important before Gutenberg invented the printing press, because lecturing was the only way to transmit information to the next generation. But now with books and internet, teachers should focus on assimilating information. Education is not just about information transfer. Students need to build mental models. After all, in a Shakespeare class, you don't have the instructor reading Twelth Night to the class. The students are expected to read the play before coming to class.

Meanwhile, Mazur came across a study on the effective of physics teaching. The study gave a so-called "force concept inventory" (FCI) test to the students before and after the course. An example question is: "A light truck and a heavy truck collide. How do the forces they exert on each other compare?" Possible answers are "A) The light truck exerts more force than the heavy truck, B) The heavy truck exerts more force than the light truck, C) The forces are the same, D) There are no forces. The trucks are just in each other's way." The correct answer is (C), using Newton's Third Law.

The student data was divided into four groups: students who had award-winning teachers, students in small instruction groups, students who had experienced a lot of hands-on demonstration in their class, and students who had teachers with the worst evaluations. There was little difference between the FCI pre-test and post-test scores. In fact, it made no difference what group the students had been in! All the students failed to learn basic physics concepts.

Mazur thought, "Well, I teach at Harvard" and wanted to prove the study's results wrong. He gave the FCI to his students at the beginning of his course and found that most of his students scored below 23/29. A score below 23 indicates Aristolian thinking and a failure to grasp Newtonian concepts. Then he gave the test at the end of the course. There was a little improvement but still over half the class scored below 23. Many of these students had scored 5's on the AP Physics exam.

You can define a statistical "gain" to characterize the student's improvement due to the course. If you plot Harvard's results along with data from other colleges, you find a gain of 23% which is much lower than the maximum possible gain of 100%.


Mazur considered various possibilities. Bad teacher? NO. Dumb students? NO. Blame the test! So he wrote his own test. He designed his exam so that each "conventional" question would be paired with a "conceptual" question. The conventional question was one you would find in a traditional textbook. The conceptual question was word based with no numbers or algebra. Moreover, he chose to do this on a topic that students had very little pre-existing intuition: DC circuits. For Newtonian mechanics, students might have real world experience that interfered with their reasoning. This could be avoided by testing them on DC circuits. An example paired conventional and conceptual question are shown below.

Conventional question


Conceptual question


Mazur found that the conventional questions gave misleading impressions of the students's performance. He had expected that conceptual question to be really easy, compared to the conventional question which requires cranking out a page of algebra. Any physicist can solve the conceptual problem in 30 seconds, with 5 seconds on parts (a)-(d) and 25 seconds on part (e). But the students freaked out on the conceptual question. The average score on the conventional question was 6.9/10. The average score on the conceptual question was 4.9/10, with a huge peak at 2/10. The students had been tripped up by the following fallacy. They thought that when the switch was closed, the current would be divided equally between the two paths (the wire with the short circuit and the wire with the light bulb). Therefore, they had all gotten part (b) correct, which is what resulted in the huge peak at 2/10. Mazur examined the correlation between the conventional question score and the conceptual question score. Students who did well on the conceptual question tended to do well on the conventional question. However, the converse was not true. Students who did well on conventional question did not necessarily do well on the conceptual question.


He realized that students were simply learning by "plug and chug", recipes, and memorization. No wonder people often complain that physics is boring! Physics is boring because students apply recipes they don't understand to solve problems. The way students try to solve problems is to look at the "problem solving strategies" box in the textbook. If that doesn't work, they find a worked problem and try to substitute the numbers. There is no real understanding of the concepts. Unfortunately, in physics, recipes only work sometimes. If a recipe only works for 75% of the textbook problems and not for the other 25%, then students get frustrated.

Imagine that you are in a room of 150 students taking an exam. As you turn the page to the first problem, you see the conventional question with the circuit diagram we just discussed. what is your first thought? Kirchoff's Law problem! So, in a split second, you have already determined the appropriate recipe to use and there is no physics left. It's become an exercise in algebra. But do students actually understand Kirchoff's Law? Clearly not, because they did poorly on the conceptual question. [My comment: Physics has turned into zoology! We just classify problems by which recipe applies to them!]

Mazur was at a loss. But then he remembered what happened after he gave the class the FCI. The students were appalled by their poor performance and wanted Mazur to go through the test question by question. He didn't have time to do that in class, so he reserved a lecture hall at night for discussion. Let's go back to the question about the light truck and the heavy truck. Mazur's first explanation was "use Newton's Third Law, done." The students looked utterly confused. So he tried again. The second explanation was "a = F/m, so even though the forces are the same, the heavy truck experiences less acceleration and feels less from the impact." Still, blank looks. Then Mazur gave up and told the class to discuss the problem with their neighbors. Chaos ensued.

He realized that students have a much better idea of what difficulties their classmates are having. The instructors learned the material so long ago, that they have forgotten these difficulties. Education is a two step process: 1) information transfer, 2) assimilation of the information. Therefore, we should give students more responsibility for gathering information.

Mazur now uses a peer instruction style teaching method. Peer instruction includes 1) pre-class reading, 2) in-class instruction focusing on depth, not coverage, and 3) ConcepTests. Each ConcepTest follows the sequence: 1) Question, 2) Thinking, 3) Individual answer, 4) Peer discussion, 5) Revised/group answer, 6) Explanation. In practice, this is how it works. The lecturer will put the question on the projector and ask the class to think about it individually. Then each student has a "clicker" and electronically selects an answer from multiple choice. After that, the students pair up and try to convince their partner that their answer is correct. Finally, the students answer the question, possibly changing their answer after the discussion. Since the instructor can see the distribution of the answers, he/she gets feedback about the class's understanding and can adjust the instruction accordingly. Thus, instead of a traditional lecture, the class becomes ConcepTests interspersed with snippets of demonstrations and the lecturer talking.

The benefits of peer instruction are that 1) there is little time to goof off, 2) there is two-way information transfer. The instructor can assess student understanding and the students can assess their own understanding without any impact on their grade.

Other colleges besides Harvard have implemented peer instruction and the results are astounding. The overall gain is 0.48 for peer instruction compared to 0.23 for traditional lecturing. Moreover, the gains are not instructor dependent.


What about problem solving? Mazur decided to stop doing example problems in class. He felt like he was simply writing the textbook on the board. Think of the following analogy. You don't learn the piano by listening to CDs.

Previously, Mazur had said that better conceptual understanding leads to better problem solving, but the converse is not true. He showed data proving this point. Since he never repeated any questions on exams, he decided it would be safe to give the exam from his traditional 1985 class to his peer-instructed 1991 class. The 1991 students did statistically better on the test than the 1985 class.

In retrospect, Mazur thinks that courses should be defined not by content, but by learning outcomes. For example, for a course on mechanics, a learning outcome could be "understanding Newton's three laws." Unfortunately, Mazur has surveyed his colleagues, and there is no consensus on learning outcome.

The audience had many questions about the practical implementation of peer instruction. Mazur said that preparing the course still takes the time, but instead of making lectures, all the time is put into writing good ConcepTests. You can develop good questions by 1) looking at mistakes on exams and 2) asking for feedback about what was confusing on the reading. For each reading assignment, Mazur has students answer two questions on the material and give feedback on what was confusing. This accounts for 10% of their overall grade.

Also, Mazur has found that it is better to reduce coverage of material. The traditional lecture course covered way too much. The peer instruction course covers less material, but the gain in understanding far outweighs the small loss of coverage.

He also tries to motivate the students by writing exams with conceptual questions. In fact, the first exam is completely conceptual. As he puts it, "it's amazing how students are driven by the exams." He also makes all the exams open-book. After all, in reality, people don't memorize. They look up information while they are solving problems.

Someone asked about labs. Mazur said that because of overcrowding, his students took lab biweekly. One half would do it one week and then the other half would do it the next week. He once gave an exam involving circuits and it turned out that because scheduling, half the students had done the circuits lab before the exam, and the other half were going to do the lab afterwards. The lab made no difference on the exam performance. In fact, the students who had done the lab did a little worse than the ones who hadn't. This just goes to show how cookie-cutter and badly-written the labs are. Mazur has just now started on the huge project of revising the labs.

The audience pointed out that students and colleagues will resist peer instruction. Students have two main complaints. First, there are the students who did well on conventional problems (5's on AP Physics exam), but do poorly on the ConcepTests. They try to blame the instructor and ask "when will we do real physics?" Second, there are students who write on the course evaluation, "Prof. Mazur doesn't teach us anything! We have to learn everything ourselves!" They are mad because they are paying $47,000 a year to be taught by their peers. Mazur tries to convince them by showing them the data and telling them anecdotes. As for colleagues, Mazur said that schools outside Harvard have implemented peer instruction and when his colleagues go to visit those places, they encounter peer instruction and warm up to it. As Mazur put it, "change comes from outside." Mazur had very little influence on "evangelizing" his colleagues about peer instruction. The point is that students and instructors have very deep rooted conceptions about how they learn.

To summarize, traditional indicators of success (class evaluations, exam scores) are very misleading. Education is no longer about information transfer; it's about how to use information.

My comments: I think the success of peer instruction is simply an illustration of ratios. Physics is a very difficult subject. In an ideal world, everyone would have an amazing tutor who would teach them one-on-one. But that is far too expensive, so we have these huge lectures in college. Peer instruction leverages students as teachers.

If I were the "smart" student in the class, I would object to peer instruction. Why should I come to class and have to teach my classmates while not learning anything from them?

The truth is that college is about learning how to teach themselves. What an instructor can do is show you how to approach the problem, what are the right questions to ask. In learning, just as in research, asking the right questions is 75% of the battle. In a sense, peer instruction helps students learn how to teach themselves, because they are forced to teach someone else and explain their reasoning. It's just like what all teachers say; they understood the material much better after teaching it.

I think one thing that Mazur fails to mention is that we still need teachers to inspire students. Difficult abstract subjects like math and physics benefit the most from an inspiring instructor.