Atik cooling question

[Skipper Billy]

I usually image with the Atik 460EX camera set to -10º - it crossed my mind as the temperature is currently -7º and dropping - what happens if the ambient temperature drops below the set point of the camera ??  Can it 'warm' as well as cool ?? Or will it just sink to the ambient temperature??  

My guess is the latter in which case I will have to drop my set point.

In which case do I really have to replace my entire library of calibration files ?? Is the difference between -10º and -20º going to make a significant difference to my calibration files ??

[SkyBound]

The cooler the better, so set it to -20

[Tim]

My Atiks typically rise to a little above ambient with cooling turned off and when they are doing something.

But! The 460ex is so low in noise that you probably aren't going to be able to discern any difference between darks at -20°, or -10°, and bias and flat frames are so short in duration that I should think the noise signal in them is irrelevant in the normal range of temps. Plenty of reports of people with 460ex's that don't even bother with darks. I have two, a mono and colour and find them very clean indeed.