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Grahame
15-08-2011, 02:25 AM
Just going to throw it out there - what does everyone use for data rejection methods in which ever flavor of software your using to stack images?

I find myself using the sigma reject method most of the time in CCD Stack, with occasional use of clip min/max also.

jase
15-08-2011, 10:56 AM
CCDStack

I use Poisson sigma-reject on small stacks (4 to 8 subs). Its very reliable at detecting outliers after good normalisation (selecting both background and highlight manually).

For large stacks (8+ subs), STD sigma-reject is preferred. Poisson can still be used however but I've found that you don't need a strong standard deviation value.

If the data is of good quality a deviation value of 2.2 works well. I'll drop down to 2 or 1.8 for mediocre. For a small stack of RGB, at times I'll drop down to 1.5 deviations. I rarely go lower than this.

Hope that helps.

Cheers

tlgerdes
17-08-2011, 12:27 PM
Favourite Data Rejection method: Telling Fred V he is full of it and moving on :P :lol:

Octane
17-08-2011, 01:18 PM
lol!

H

jase
17-08-2011, 01:47 PM
You may be in for a surprise. With poor data normalisation, Fred V may not be computed as an outlier thus not rejected. As a result Fred would be embedded to increase 'signal over noise'. Put another way, he may be full of it, but his parted wisdom is 'gold over crap'. :D

Geoff45
21-08-2011, 04:37 PM
Poisson for Small stack, STD sigma reject for large ones. I aim at getting between 1 and 2% rejection on most of the frames.
Geoff

Grahame
21-08-2011, 09:23 PM
Thanks everyone, general consensus seems to be heading the same way - I have been using roughly the same percent rejection however always used poisson reject for all my stack rejection.

Grahame.