How to take Darks, Bias subs

[BlueAstra]

Just a thought, while its cloudy I thought I would start a library of dark subs. I assume the important thing to note is the temperature, but do I also need the camera attached to the telescope? I could just put the camera outside with its lens cap on and shoot a series of 1, 2 , 4, 8 min subs and store them in a folder labelled with the temperature. This would be OK if DSS or Maxim is just looking for 'hot' pixels, but do the various stacking programs also detect the intensity profile of the dark (can there be one?) ? In which case I would need the scope.

Does the above argument also appiy to bias subs? And is the bias noise also dependent on temperature?

[Jupiter Martin]

Not a hundred percent on this but I belive they need to be at the same focal length so yes they need to be conected to the scope.

[Beyond_Vision]

No you just need to cover the camera to stop light getting in. You do not need the scope or lens. The exposure needs to be the same time as per the light frame and the temperature needs to be within a degree or so of the light frame. The bias is a the quickest exposure the camera can do. It may be worth doing the bias at the same temperature but is not so critical.

Regards

Kevin

[BlueAstra]

OK, thanks for the replies. Off to get a digital thermometer tomorrow!