[ATMoB-discuss] First photo from C14/ST7

[Bruce Berger]

I may be misunderstanding something. I thought the dark exposures were
supposed to null out the hot & dark pixels. How do you subtract them
separately? Should I apply a 2-4 pixel Gaussian blur?

Bruce

-----Original Message-----
From: mmotta at massmed.org [mailto:mmotta at massmed.org] 
Sent: Tuesday, August 08, 2006 1:53 PM
To: bruce at scopemaker.com
Subject: RE: [ATMoB-discuss] First photo from C14/ST7

Choose only those that have tracked well.
do basic processing on each (Dark/ flatt field/ bias).
Then, do the hot and dark pixels on each.
Then, stack your best ones, and do all higher level processing (digital
processing, masking, etc ) on the combined deeper stacked image.

Mario

On Tue, 8 Aug 2006 13:44:17 -0400, "Bruce Berger" wrote:

> 
> Thank you. So here's a question - I have about 8
images
> @ 3 or 5 minute
> exposures. Should I align and stack, and THEN apply Dark & Bias 
> frames, or should the Dark & Bias be applied to each frame before 
> stacking?
> 
> I do not have MaxIm, but I do have Registax, CCDSoft 5.0 and Photoshop 
> CS2.
> 
> Bruce
> 
> -----Original Message-----
> From: mmotta at massmed.org [mailto:mmotta at massmed.org]
> Sent: Tuesday, August 08, 2006 1:35 PM
> To: valleli at rcn.com
> Cc: bruce at scopemaker.com; atmob-discuss at atmob.org
> Subject: Re: [ATMoB-discuss] First photo from C14/ST7
> 
> Look on the black "sky" and you will see single pixel white dots. 
> Those are hot pixels.
> Mario
> 
> On Tue,  8 Aug 2006 13:19:35 -0400 (EDT), valleli at rcn.com wrote:
> 
> > 
> > Mario,
> > 
> > I see the dark pixels, no problem. Not sure what you
> are referring to
> > for 'hot' pixels.
> > 
> > Is it the mottled (grainy) background?
> > 
> > I downloaded the JPG and then viewed it in
Photoshop.
> > 
> > What I saw on the laptop screen had a lot more
detail
> in the ring than
> > this processed exposure shows.
> > 
> > Would binning for such a small object have been
> helpful?
> > 
> > Paul
> 
> 
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