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Invader Xan
03-04-2005, 03:45 PM
Hey people...

If it was up to me, I'd try and avoid scanning glossy printouts and suchlike... Though sadly "the customer is always right", as that old adage goes. So I was just wondering if anyone has any good methods of descreening scanned images in Photoshop.

I usuallylike to put a Smart Blur on the blue channel in RGB mode, then switch to Lab colour and use a gaussian blur on the two colour channels. That works ok on same size scans, but it's not so great for any image that needs to be blown up.

Another handy trick (which works well in the right context) is to duplicate the image layer, use curves to burn it out a bit (works best in RGB mode), apply a fairly strong gaussian blur and then decrese the opacity (sometimes changing the blending mode to Screen works well too. Using a moderate opacity like that tends to put a soft focus effect on the image, a la original series Star Trek.

Incidentally, the abovemethods are also good at removing those blocky distortions caused by too much Jpeg compression, or if someone sends you alow resolution image. Sometimes these things are salvageable, and it's easier than trying to explain image resolutions to clients.

All the same, I'm sure there are other techniques that can help.
Any suggestions?

I would've taken over the world, but I got distracted by shiny things.

Ooo! Shiny things!

1984
03-04-2005, 05:42 PM
I use two tricks as well, I'll scan with the documnet at an angle to combat moire, and scan at a real high rez and shrink the image down some.

Blah Blah. Pitter Patter.

Invader Xan
03-04-2005, 06:15 PM
Scanning it at an angle...? Interesting. I'll have to try that, thanks. =)

I would've taken over the world, but I got distracted by shiny things.

Ooo! Shiny things!

Allen Harkleroad
03-04-2005, 07:00 PM
If you can screen it 45 degrees opposite it will remove the moire as well. We have acetate 'dot' screens and we just 45 degree em when scanning a print that was previously screened for print.



Allen Harkleroad
'I didn't do it... You didn't see me... You can't prove a thing...'