Quote:
Originally Posted by John K
Bumping this thread back up - possibly belongs in terms of my question in the astro-photography equipment section.
Over the last 12 months have used the S/N ratio graphs that Richard shared here to get the best results with my Canon 400D.
Now my camera is in the process of getting TEC cooled, and I am wondering what the new S/N ratio numbers will be? It will go 15 degrees below ambient so in winter this means well below zero.
So the question becomes, has anyone done some S/N ratio tests with a cooled DSLR that's close to the 400D sensor or an older model perhaps that they can share?
One of the things I am hoping with my modified and cooled to be DSLR, is to have better results with something like 10 minute exposures of faint galaxies where I think the non-cooled DSLR CCD's let things down.
Any info that people can share would be great.
John K.
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I did some testing when I installed active cooling on my 1000D (Digic 3 and live view,m but otherwise almost identical to the 400D). I was able to dig up this result for 0 C.
I had some condensation troubles with my setup when operating it below the dew point, so in the end I went for a setpoint of 10C - still well below the typical operating temp of the camera, but above the dew point on most evenings. My testing did not show the drop in SNR at longer subs that it did with the uncooled camera. rather SNR increased with sub time. Consequently I decided to run with 10min subs with the cooled 1000D, with good results as shown
here.