Does anyone have any figures for the dark current of an EOS 300D? I've tried to estimate it doing two 8min dark frames at ISO 800, subtracting them and then plotting the histogram.
My estimate is approx 0.5 electrons/pixel/sec at 18C in the main central area the CCD but there are some patches of higher dark current towards the edge (which are visible as reddish patched in the processed image). I wondered how realistic this is or if my methodology is flawed.
Never done it Mark - I believe that you do get some amp glow though on long exposures. When you took the darks did you make sure that the viewfinder was blacked out as well as front (lens) of camera as I believe you can get light leakage in via this.
Cheers, John.