Hi Buldric,
I dont know of many people that take Bias/Offsett frames, The only ones that I worry about are taking Darks and Flats.
When I take dark frames I always take a series of them starting with the shortest exposure that I may take on an object, all the way to the longest planned exposure, this will remove any readout noise from the CCD chip and hot pixels, Normally I take about 10 of each, starting from 1 second all the way to 45 seconds, I hardly ever go over a 45 sec sub.
IT would seem to me that a dark will eliminate the task of the Offsett / bias procedure you have quoted, that one has me intrigued???
A flat frame is very important, and is used as explained in your quoted post, the only part I dont like is the way they go about explaining how to create one.
I use the sky at twilight, you need a very even light, but not as strong as that quote says and certainly not with a towel! that will not give you an even illuminated field.
The Flat frames are averaged out to create a master flat frame.
With the darks you have to have an avg master dark for each planned exposure.
lets say for example that I plan on only Deep sky work, and I plan on only 30 second subs for the evening.
So I would take 10 or more darks at the ambient outdoor temp at the time, at 30 seconds each with my lens cap on my telescope.
while flats only need to be taken from time to time the darks must be taken before, halfway thru the night, and at the end of the night, this is only because of temperature changes.
Dennis
