The last set of images (showing removal of the texture in print paper
with Neat Image) illustrates a technique also shown by Ctein in his book
on photo restoration "Digital Restoration From Start to Finish"
(recommended). Neat Image can develop a profile that recognizes the
texture as low frequency noise while the control sliders can be adjusted
to leave high frequency detail alone. Ctein manages to make an even
better job of it than Koren's example since (for the particular case of
textured paper) he chooses to rephotograph the original rather than
scanning it. By using copy lights at 45 degrees he can eliminate the
shadowing in the texture seen by the scanner but not the camera. The
resulting texture in the copy is still visible but not nearly as strong
as in a scanned image and Neat Image is presented with a simpler problem
to solve.
Chuck Norcutt
ws wrote:
>> <snip>
>>
>> Of course noise reduction software might do a much better job than
>> simply resizing the image here but I was surprised at how long the grain
>> persisted in even modest enlargements from a 6x6cm frame.
>
> That would be the conclusion of
> http://www.normankoren.com/Tutorials/MTF8.html
> Note the NI examples on that page.
>
> Wayne
>
>
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