Certains scans "speckled"

  • Thread starter Thread starter Jim Hutchison
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J

Jim Hutchison

This link is an example of a film neg scan that has allot of
"speckling" that mystifies me.

http://www.jamesphotography.ca/speckle_example.jpg


It's scanned on a Minolta Dimage Dual Scan III, 8x sampling at 18 bit,
1420 DPI.

Seems to me these "artifacts" (if that's what they are called)
shouldn't be there after sampling 8 times. I could understand the
software having difficulty with black, but that doesn't explain why
the entire picture is like that.

Other scans look great, and the actual print of the neg from the lab
is outstanding...... making me hesitant to keep flouting this
scanner. I must be missing something...

Any insight or ideas? Thanks in advance.


jim h


~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

http://www.jamesphotography.ca

More than photographs: free downloads, prizes for every 1,000th visitor, a bit of humour...
 
Jim Hutchison said:
This link is an example of a film neg scan that has allot of
"speckling" that mystifies me.

http://www.jamesphotography.ca/speckle_example.jpg


It's scanned on a Minolta Dimage Dual Scan III, 8x sampling at 18 bit,
1420 DPI.

Seems to me these "artifacts" (if that's what they are called)
shouldn't be there after sampling 8 times. I could understand the
software having difficulty with black, but that doesn't explain why
the entire picture is like that.
Click to expand...

Is this the infamous "grain aliasing" effect? The fact that it is
there even when sampling 8 times means it is not random noise
generated by the scanner. I have had this on some negatives too, with
a Nikon Cool Scan V. And scanning multiple passes showed exactly the
same pattern on every pass.

I found the best way to reduce it was to scan at maximum resolution
(4000 dpi on the CoolScan V) and then downsample the output to the
required resolution. I found that downsizing the raw file in VueScan
or downsizing the output image in an editor with bicubic interpolation
gave very similar improvements.

Neat Image also gave quite good results as did selective use of image
editor's median filter or edge preserving smooth. But best of all was
the downsample.
 
Looks like Dust & Scratches to me - use a Dust & Scratches filter - ICE if
the Dual Scan III has it, Vuescan's if you're using Vuescan, or PS filters
or plugins.

Maris
 
Gawd no. Its some kind of digital noise

I found the problem could be minimized by setting the white and back
points to a slightly narrower range.....






Looks like Dust & Scratches to me - use a Dust & Scratches filter - ICE if
the Dual Scan III has it, Vuescan's if you're using Vuescan, or PS filters
or plugins.

Maris
Click to expand...

jim h


~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

http://www.jamesphotography.ca

More than photographs: free downloads, prizes for every 1,000th visitor, a bit of humour...
 
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