Re: [APML] Beginner scanner images

[Jerry Lodriguss <jerry@astropix.com>]

Hi Steve,

Looking at your histograms for that scan, you are clipping some data in the 
highlights on the right hand side in the red and green channels. The bright 
core of the Lagoon has definitely lost detail because of this.

The left hand of the histogram in the green channel also looks weird, like 
data was clipped there and then the curves re-adjusted later. This may be 
an artifact because there is that thin strip of black on the bottom edge of 
the frame.

Try cropping in on the prescan to get rid of that black strip and the 
vignetting in the corners, and try letting the scanner set the exposure on 
that crop. Then look at the histograms.  Ideally you want the histogram to 
stretch from one end to the other without anything cut off on either end. 
Then you can leave the settings alone and remove the crop and scan full frame.

Jerry

At 06:45 AM 7/18/2003 -0700, you wrote:
>Thanks Stuart!
>I rescanned the RG200 M8 shot last night and put a raw 1000 by 700 pixel
>copy up along with the curves shown by the scanner in prescan. This time I
>could see some vignetting present, and spent a way too much time trying to
>help the image.
>
>This scanning stuff is tough. But I've gotten orders of magnitude more
>detail out of the shot than my overpriced local photo lab!
>
>For anyone interested in fiddling with the scan (about 1.2 meg), its at:
>http://www.sonic.net/~banburys/June30,2003/RG200M8RescanJul17.jpg
>
>and the scanner curves are at:
>http://www.sonic.net/~banburys/June30,2003/Prescan_curves.jpg
>
>Apologies for the names--I'm not very creative at 2 AM!!
>
>Steve
>
>
>Stuart Heggie wrote:
>
> > Steve, I really liked all the images. I think the advice you have gotten
> > back on the scans will improve them but what a great start!
> > Stuart
> >
> > steve banbury wrote:
> >
> > >I've posted some shots taken last new moon and scanned with a newly
> > >acquired Scan Dual III at:
> > >
> > >www.sonic.net/~banburys/June30,2003/
> > >
> > >Constructive comments would be appreciated.
> > >Go easy on me guys--this is my first attempt at film scanning and even
> > >with Jerry L's CD I found scanning a negative  to be a real challenge!
> > >
> > >:^} Steve
> > >
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