Photographing the transit was an interesting experience. I've never photographed the sun before. I've heard claims that photographing the sun can damage your camera. Although I'm not convinced (I'm fairly certain most of these claims are exaggerated) I didn't want to take any chances. So rather than use my good camera and lens, I used my original Canon Digital Rebel and Sigma 70-300mm lens, both purchased in 2004. Neither of them have been used since about 2008, so I figured if something bad happened, it was no big loss.

At first I tried photographing without any filters. I set all the camera settings to give me the darkest exposure (ISO 100, f/32 aperture, 1/4000 second shutter speed). Needless to say, even that wasn't enough to get anything more than an overexposed white blob. So I added a filter, a 3 stop neutral density. That wasn't enough so I added on my polarizer. When then wasn't enough, I borrowed my wife's polarizer to add to the stack. That was getting close, but still wasn't enough. I added on an adapter and my Cokin polarizer. Finally I was able to get a good exposure with no overexposed spots. And it only took 4 filters (a 3 stop ND and 3 circular polarizers) for a total of about 9-10 stops of light reduction (filtering out more than 99.8% of the light) combined with the fastest shutter speed, smallest aperture, and slowest ISO to accomplish it.

Having solved the exposure problem, the next difficulty was aiming and focusing. Normally that's not such a major issue. However, even with all these filters in place, I still wasn't about to look through the viewfinder (in fact, I taped over it so I couldn't accidentally look, since it can be hard to override instinct), so I needed to do this blindly. For focusing, I just put the lens into manual focus mode, focused the lens to infinity, and then backed off a tiny bit (backing off isn't necessary for most lenses, but this is one of those odd lenses that focuses "slightly beyond infinity").

Aiming was the more difficult part. When zooming in (especially at the levels I was using) you have to make extremely small adjustments to your aim. Even what seems like just a very slight adjustment can be enough to take you from too-far-left to too-far-right. So the way I did it was that I first zoomed all the way out. Then I took a photo and looked at the LCD. I noticed where the sun was and tried to adjust the aim so that the sun was centered in the photo. I'd repeat this aim,take photo, review cycle until I had it pretty close. Then I'd zoom in about 1/3 of the way, repeat the cycle until it was centered, zoom in another 1/3 of the way, repeat, and then zoom in all the way. If at any point I screwed up and moved the aim too far one way or the other, it was nearly impossible to correct without zooming all the way out and starting over.

At first I was photographing with just my 70-300mm lens, which wasn't too difficult for the aiming. However, I wanted more magnification than that, so after my first batch of photos (and before the clouds cleared), I added on a 2x teleconverter to double the magnification. This gave me a better image, but made the aiming much more difficult. After photographing for about a half hour this way, I added on an additional 1.4x teleconverter, for a total of 2.8x magnification (on top of the magnification of my 70-300mm lens). This got me the largest image of the sun, but made aiming nearly impossible. This would have been MUCH easier if I had a tripod mount better suited for tiny adjustments, like you usually find on a telescope mount.

The end result was pretty satisfying. I was able to get a nice exposure, fairly sharp, and was able to make out several sunspots.

Photographs taken before 7PM were done from my home. Photographs taken after 7PM were done from the astronomy balcony and the University of Michigan - Dearborn.