Forum: Photoshop


Subject: Moire pattern madness

BxMomo opened this issue on Jul 30, 2002 ยท 5 posts


BxMomo posted Tue, 30 July 2002 at 2:49 PM

First, let me say hello to all. Second,....help! I need help in removing a moire pattern. Is it possible???? I only, unfortunately, have access to PhotoShop 5.5. My clients seem to only possess film from which they want me to scan their art from; which constantly gives me this headache...Any advice, anyone?


Alpha posted Tue, 30 July 2002 at 4:37 PM

What type of film are you getting, and what type of scanner are you using?


retrocity posted Tue, 30 July 2002 at 10:41 PM

BxMomo, glad you stopped by... Check to see if you scanner has a setting for "Descreen", this will knock down "some" of the Morie Pattern. Next in PS create a layer and run a Gaussian Blur (Filter --> Blur --> Gaussian Blur) at a low setting (Radius = 1.1 pixels). To bring back some of the detail you can run a Sharpen filter. Play around with the settings but as long as you are doing this to a Layer and not you Background image you can always delete the Layer and try again. You might want to see what you get if you change the Blend Mode on the Gaussian Blur layer to allow some of the original image show through. my2c :) retrocity


Heronheart posted Wed, 31 July 2002 at 8:26 AM

You can try the Despeckle filter in Photoshop. Also, the moire will often be worse in one color channel then the others. Concentrate your efforts on that channel. - Ken Heronheart -


thyrain posted Wed, 31 July 2002 at 10:04 AM

I've found the best way to take care of moires right off the bat from film is to descreen, if possible, right with your scanner at the same linescreen as the media you're scanning (ie, if you're at 300dpi res, set descreen around 155lpi). That's removed most of the junk for me, but what heronheart says is true also, you do tend to get more moire in one channel than another, so that's something you'd definitely want to doublecheck even if you'd descreened right from the scan.