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Subject: Re: [M]: Re: RE: Re: PictorView 6.4 noise
From: Chris Heapy
Reply To: mapug@shore.net
Date: Sat May 09 00:52:47 1998

Bob Freeze wrote:
>
> I've done some playing around with the histogram in 6.4. I don't know
> if anyone else has tried this, but...
>
> After opening an image and subtracting the dark, before making any
> other adjustments, I manually set the background to zero and the range
> to 65535. This lets you work in from both ends with a complete view
> of the histogram instead of just seeing the central portion. I don't
> know why I've never done this before. I've always just accepted the
> default histogram.
>
> Overall I'm finding images scaled this way have less overall
> brighness, but have a softer, less grainy appearance more like the
> scaling that 2000IP does. I certainly like the results better for
> some kinds of images.
>
> Anyway, the images don't look as "noisy".
>

Yes, that's the procedure I use, particularly on the focus window just
prior to using the selection box - the focus window then 'remembers' the
settings while you are focussing.

However, if you take a normal image, adjust the display as described
above until it's acceptable, then take another image - you have to
repeat the process each time. I often take 5 (or more) images of the
same object and select the best one to save, or the acceptable ones for
stacking, and would like the same parameters be applied to each by
default - until I change something.

Chris

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