From: Milton Aupperle <milton@outcastsoft.com>

Date: August 31, 2009 10:25:56 AM MDT

To: Astro_IIDC@yahoogroups.com

Subject: Re: [Astro_IIDC] darks & flats

Hi Willie;

On 31-Aug-09, at 12:47 AM, Willie Strickland wrote:

When a dark frame is created, is it stored to disk?  If so where?  The  

same question for a flat frame.

No neither are stored. It's kept in Ram and applied that way.

I have just been creating averaged frames for flats and darks, so that  

I will have some masters to use.  I also have experimented with  

capturing movies and processing them for darks and flats, but it seems  

to be overkill.  The results are quite similar.

They can be over kill unless your :

a) shooting longer than probably 30 second exposures once your out to 10+ minute exposures, it really becomes necessary.

b) not stretching / processing / brightening the image very much in post processing.

c) Your CCD has bad Amp glow which causes the top left corner and top area to brighten as exposure increases, almost like a light leak.

HTH..

Milton J. Aupperle