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Monday, November 12, 2012

It's a bird! It's a plane! It's a flying saucer! It's ...

First time to spot the International Space Station and shoot it. It's fainter to the naked eye than I expected. Not least because it was only 34 degrees (at its maximum) above the eastern horizon to begin with. Venus was rising and the station was much dimmer. I almost didn't recognize the blip as the station. As a matter of fact it was already close to the northeast (where it would "set") when I spotted it. According to NASA it would be visible for just two minutes. True enough, as NASA claims, it zips across the sky at the rate of an airplane.

I initially wasn't planning on shooting, just checking whether I could see the station and if I did then I'd note its brightness and speed, using the observations in planning a future shoot. But at the last minute I said to myself, What the heck. I'll get my gear out and try anyway. Little beginner's luck here. Though I was able to--a miracle in itself--capture the station, the images were crappy.

While waiting for the appointed time, I preset the camera to ISO 3200, 1/50", f/10. Shot the very first frame with this setting. But I subsequently decremented the shutter speed until it was just 1/10". I kept the aperture fixed because any larger and lens sharpness deteriorates. In what was going to turn out to be the very last shot--because I couldn't see the station after that--I bumped up the ISO to the maximum of 6400 (I wasn't even going to use "H"--ISO 12800--because of its very high noise) since judging by how quickly the station was moving across the frame in the viewfinder and because I was so damn concerned about camera shake, 1/10" was the slowest I was willing to go.

Was able to shoot a mere seven frames. I learned pretty quickly that tracking a faint object racing across the night sky with a long lens while trying to keep camera shake to a minimum even as it's mounted on a tripod most certainly isn't a walk in the park.

In the image below the station appears simply as a bright blob. 

Canon T3i, 1/20", f/10, ISO 3200, EF 75-300mm III @300mm, 10-second self-timer enabled

Because of the time constraint I was in panic mode and was fumbling over the camera's controls. I had preset the camera with both mirror lockup and the 10-second timer enabled to dampen camera shake from pressing the shutter button. Not an excellent choice. I discovered that ten seconds is about the amount of time the station takes to traverse the frame of a 300mm lens (APS-C sensor). So I found myself actually re-aiming the camera after I had pressed the shutter the second time (the first press just locks the mirror up). The mirror was already out of the way so I was doing this without feedback of whether I'd be able to catch the subject in the frame (I didn't even bother using Live View).

I disabled the timer towards the latter of the shoot. Unfortunately, there aren't any dots in the images which I'm confident of as being stars. That would give me a barometer as to how much camera shake there was. After much poring over the images I've concluded that all of the white specks in the images are digital noise, and what I thought were solar panels of the station are more likely to be streaking caused by camera shake after I disabled the self-timer. Dang!

1/10", f/10, ISO 3200, 300mm, self-timer off

In lieu of the self-timer I may have to use a remote shutter control.

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