Canon 40D Night Time Exposure Tests: Part One

For the past five years, I've been using a Canon D60 for all of my night time work. When it was first introduced, I believe it was the only digital camera capable of shooting a whopping four minutes (under cool temperatures) without producing unacceptable levels of noise. Since then, sensor technology has improved. Clean exposures of up to ten minutes without noise reduction are not uncommon. And longer exposures of up to one hour, using in-camera noise reduction, are also possible.

(Click here to see the 100% crops taken at various long exposure intervals)

Last month Canon introduced the EOS 40D, the forth-generation replacement for the D60 (don't be confused by the naming conventions... this lineage went D30, D60, 10D, 20D, 30D, 40D). Last night I conducted some long exposure tests with the 40D. The subject isn't interesting, but I didn't have time to drive somewhere more interesting and start jumping fences.

I've uploaded the various 100% crops to this Flickr set, which also includes some daytime ISO tests. The shooting parameters are in the title of each shot.

Since my preferred ISO setting for night shooting has always been 200, I took most of these shots at ISO 200 over 3, 6, 9 and 12 minute exposures. I also had time for one 3-minute ISO 100 exposure to determine the difference between ISO 100 and 200 at long exposure.

Keep in mind that you can't directly correlate daytime ISO comparisons to long exposure night shots because the noise increases as the duration of the exposure increases (it's also effected by the temperature of the sensor). I may add more examples of different ISO/exposure combinations (along with in-camera noise reduction and Noise Ninja post-processing) in the future.