Re: [APML]: Star Trailing Reduced by Image Processing

[mwcook@concentric.net]

The Astro-Photography Mailing List
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Actually, I believe the side effect is similar to reduced 
exposure rather than smearing.  When combining in Darken
mode, the non overlapped area is not added to the final image
resulting in a slice effect for the trailed image.  This
also has the effect of reducing the graininess of the image as
well as darkening the photo.



> The Astro-Photography Mailing List
> ------------------------------------
> 
> > >Very interesting technique, but didn't the result smear the actual image? 
> > 
> > Help me understand this; wasn't the original image smeared by the trailing?
> > Didn't the processing actually unsmear it somewhat? 
> 
> 
> Hi Robin
> 
> If you take a look at the image I think you'll see what I mean. The
> original image is smeared slightly but the trailing removal
> technique smears the image much more. Although the stars look better
> the nebulosity in the image looks much worse, to me at any rate. 
> You need to study the removal technique in PW to understand why it
> happens this way.
> 
> Regards
> --Philip
> 
> Philip Perkins  --  philip@astrocruise.com
> 51 27'N 1 36'W  --  Wiltshire, UK
> 43 54'N 5 32'E  --  Luberon, France
> Astrocruise     --  http://www.astrocruise.com
> 

de Mike, AF9Y
http://www.webcom.com/af9y
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