Quote:
Originally Posted by gregbradley
A couple of nice shots there Steve.
360 seconds is kind of short for one shot colour though.
I talked with Alan Homes of SBIG one time as I had a one shot STL11.
His advice was to take the longest subexposure time you could like 20-30minutes to get the best results.
I think this is because the Bayer matrix causes the chip to lose a fair bit of QE (sensitivity) and also because it reduces the colour noise.
I think the best strategy is to max out the cooling - don't worry if its an odd number, use adaptive darks (in CCDstack you can select different ways of scaling your darks - I found it works really well). And to go for the longest subs you can with your tracking.
Greg.
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Thanks Greg ...........
I don't think my polar alignment would be accurate enough for 20-30 min subs and I haven't got to grips with drift aligning. I think I would get field rotation if I tried stretching it out that far. I remember doing a 20 minute sub once from here and it seemed ok actually but when I've tried longer subs since they don't work out well. When I get some clear nights and no wind I'll see how far I can go.
I use adaptive darks option in CCDOPS to compensate for any slight temp differences between exposures when I convert to fits files before stacking in DSS.
