Re: [APML] Push Processing (was Scanning slides)

[Alan Voetsch <alanv12952@yahoo.com>]

Hey Dave,

--- "D. Kodama" <kodama@alumni.caltech.edu> wrote:
> But as mentioned earlier, the main benefit to pushing is not so much
> the speed as the lightness of the background for scanning.

Finally, I now understand that. Because I've never used slide film I
have not paid much attentuion to the posts regarding it over the years.
 
> It's true that push processing will increase the grain, but even at
> +3
> push, I think it's far less grainy than an equivalent negative shot
> because far less post scan contrast enhancement is necessary for the
> already contrasty positive than the rather flat negative.  The
> contrasty
> positive does make high contrast objects saturate, but in general,
> for subtle nebulosity, it's a benefit.

Are you talking objects like M8, M42 as far as high contrast is
concerned? Or, clusters? Seems like most objects I'm shooting are
pretty subtle. Then again, generally, almost everything we shoot is
subtle. I think, as I mentioned in my reply to Carlos, I'll give it a
try with a variety of objects and see what develops.
 
> My normal procedure is to go with a +2 push with E200.  In southern
> California, I get a light background in 45 minutes at f/4.  In the
> dark skies of Namibia, I went with 60 minutes

Is there anyone besides me who has NOT been to Namibia to shoot? 8-)

Thanks Dave,
Alan



=====
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& http://www.pbase.com/avoetsch12952/fs102


		
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