A couple of my secondary applications asked for a photo... here's the process I used.
It probably sounds excessive, but I think it worked really well, and I don't think it took as long as you might think!
1. Grab a friend and a digital camera
2. Have the friend take literally 50-100 photos of you
A) Wear at least one light-colored shirt and one dark-colored shirt. Your shirt can be dressy here, but they'll see you in your best dress at the interview, so no reason to be worried here. Just make sure you don't have any logos/print/icons etc and anything is fine. In the picture I ended up using I was wearing a solid, dark-blue t-shirt. (I got interviews everywhere that they saw this, so it didn't hurt me!)
B) Stand in front of two different backgrounds for the photos. Both should be solid (no texture) and non-shiny. One should be light-colored and one should be dark-colored
C) Mix and match your outfit with both backgrounds
D) Take close-up photos. Head shots. Now is not the time to show off your biceps or your boobs. The photo might be very small when it gets printed, so make sure your face is clearly visible. Your face itself should take up about 1/3 of the area of the photo when you're done.
E) Although you should take lots of photos (50+), it really shouldn't take a long time. Have your friend just keep taking them quickly while you alter your expression. The key is to generate lots of variation from one photo to the next.
3. Import them all into your computer (I have a Mac, so I import them into iPhoto). Don't delete the raw photos from your camera until the last step!
4. Immediately delete any that you know you don't like. (Continue doing this throughout the rest of the steps!)
5. Convert the photos all to grayscale. Some schools might not print them in color, so I think it's safest just to make sure that your photos look good in grayscale!
6. Go through them one-by-one and adjust the contrast. I think most digital cameras have too little contrast anyway (actually, this was an argument my physics professor put to us), but since you don't know how well their printer/monitor will deal with intermediate tones it's best to just increase the contrast anyway.
7. Crop your photos to make sure your face is centered and that it's a close-up of your face.
8. Keep deleting photos as you go until you're down to 5 or so photos that you really like. Now get some opinions from some other people about which you should send.
9. Take the opinions of others into consideration, but ultimately you have to pick a photo that you feel confident about. Go with your gut!
10. Now do a final edit. Start from scratch with the original photo (use the "revert" function if you have it, or otherwise re-import from your camera).
A. Center and size your face appropriately, then make a few copies
B. Fiddle with the contrast and brightness until you have it just right. Some programs will also let you play with things like highlights, shadows, sharpness, and noise. Play with all of these things, but don't make yourself go crazy trying to make it perfect 🙂
Now you have a photo that will look good on any printer or any computer monitor, at any reasonable size. May sound like a lot of steps, but I really think of this as a fool-proof method
🙂