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View Full Version : "Pepper grain" on Scitex Eversmart Pro II scans



kipdent
26-Jul-2008, 11:10
To all who have experience with this scanner, I wanted to ask if anyone has noticed what appears to be exaggerated film grain on their scans. I do "push" the resolution to 4000dpi if anyone thinks that has something to do with it, but I notice it on all types of film and even more so on negative color film.

The overall quality of the scans I get from this machine is incredible; I just think it is odd it presents many images with visible, black specks of grain in smooth areas like blue skies more than I think it should.

Thanks for any help!

sanking
26-Jul-2008, 11:24
The pepper grain effect, which can also be obtained with IQSmart scanners, is an artifact of the default sharpening, which the scanning software reverts to if you do not set it to something else. I would recommend either using no sharpening, and then do your input sharpening in Photoshop, or use Soft Sharp. Soft Sharp does not give the pepper dot effect and appears also to smooth the grain. I find Soft Sharp very useful with MF negatives.

Check to make sure which sharpening routing is selected just before you scan. If you make certain changes, say RGB to Grayscale, or vice-versa, the scanning software resets to Default Sharp, which I don't like because of the pepper dot effect.

I believe it is better practice to rez up the file when scanning with the EverSmart scanners than to do so later in Photoshop. The reason is that the resolution of the scanner (Pro and Pro II) is 3175 spi in one direction, but 8020 spi in the other direction, so scanning at 6350 does result in more resolution than scanning at 3175 spi. And even if the extra resolution is not needed I like to scan at 6350 spi and then downsize to 3175 spi. This reduces noise and minimizes grain.


Sandy King




To all who have experience with this scanner, I wanted to ask if anyone has noticed what appears to be exaggerated film grain on their scans. I do "push" the resolution to 4000dpi if anyone thinks that has something to do with it, but I notice it on all types of film and even more so on negative color film.

The overall quality of the scans I get from this machine is incredible; I just think it is odd it presents many images with visible, black specks of grain in smooth areas like blue skies more than I think it should.

Thanks for any help!

Ben Syverson
26-Jul-2008, 13:29
Apparently "pepper grain" comes from nanoscopic air bubbles in the plastic base of the film... It's especially evident when the scanner uses a small light source, since this gives the bubbles a hard shadow. It's less visible on scanners with softer illumination. For example, scanned on a Coolscan V, there may be a lot of pepper grain, but if the same transparency is scanned on a Coolscan 9000, it should be less visible.

As for getting rid of it without changing scanners... I'm not sure. If you're not opposed to digital manipulation, you can mask off homogenous areas like the sky, soften the mask, and then apply a healthy amount of Gaussian Blur, "Dust & Scratches," etc...

kipdent
26-Jul-2008, 22:19
Sandy--

Thanks! I never knew the Eversmart reverted to Default Sharp after changing settings. I'm sure this is what's happening, and I now will go fix it! Thanks so much for the gem-

Kip