Re: [APML] Benefits of Registar?

[Matt BenDaniel <matt@starmatt.com>]

Kevin,

RegiStar is one of the best tools to use for stacking. Stacking takes 
multiple shots of the same subjects, registers them, and combines them. The 
typical combination method is "average". The purpose of this is to increase 
the signal-to-noise ratio, where the noise is the grain pattern in each 
image. Typically 2 to 10 images are stacked. When the grain is reduced, 
faint detail becomes better defined.

Stacking is not the only way to show more faint detail. Other methods 
include using longer exposure, a darker/clearer/calmer sky, finer grain 
film, filtration (e.g. H-alpha), larger aperture, longer focal length, 
faster focal ratio, recording medium with higher quantum efficiency, better 
focus, better tracking, etc.

Matt

At 05:18 PM 5/22/2002, Kevin Wigell wrote:
>Newbie question: Can anyone explain to me what are the benefits of 
>stacking images with Registar (besides grain reduction)?
>
>I downloaded the trial version and used it to combine two good film images 
>of M42. The reduction in grain was obvious, but otherwise I didn't see any 
>big improvements.
>
>Will stacking images with Registar bring out more contrast or fainter 
>details? I have a decent film image of M51 (it's no Tony Hallas or Rob 
>Gendler), but I would like to improve the image contrast (darken the sky 
>background) without losing the fainter details, as well as just bringing 
>out more of the faint stuff. Here it is if anyone wants to look at it: 
><http://home.twcny.rr.com/kevinwigell/images/M51b.jpg>http://home.twcny.rr.com/kevinwigell/images/M51b.jpg 
>(I told you it was no Tony or Rob). This is 90 minutes on RG200, 
>unhypered, 10" LX200 f/10. Can I expect to get more of the faint stuff if 
>I stack it with more similar images?
>
>Kevin Wigell

--
Matt BenDaniel
matt@starmatt.com
http://starmatt.com


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