I have a slide of the World Trade Center which produces a moire pattern on scanning. I read a procedure using PS7 to remove moire, but it uses separate color channels. I was wondering if there is a method in PSE to remove the pattern.
I have searched some of the archives, but most of the threads seem to be about scanning from printed media. The pattern disappears when I reduce the size of the image, but I'd like to print near the maximum resolution of the scan, so that method will not really work.
Thank you.
#1
Carl, Beth,
I just noticed something very interesting. I opened the image to try the method that Carl described. The image opened at 16.7% magnification, and I zoomed to 25% to work on it. The pattern disappeared! Every magnification shows a different pattern, so I think the pattern is coming from monitor issues, not image file issues. I'll print it later today and let you know what happens. The pattern is not there at 100%, which leads me to believe it will print fine. Moire is a nasty beast. Maybe it will show up at different print sizes.
Beth, I think the methods for avoiding moire during scanning are all related to scanning from print media.
Thank you both!
Eric
#2
I printed a 5x7 and it came out fine. I don't think it will be an issue at larger sizes either. Thanks again.
#3
Eric,
In case you need it for another problem, Rich's technique is to improve "posterization", or color banding, which is what I think of when I hear "moire". But maybe I don't know what "moire" means.
Your change with zoom sounds like aliasing due to dots from printed material (when screen dots & image dots don't match up & a pattern results due to ignored image dots, effect varies with zoom). Some scanner software has a descreen button for that, but Forum common knowledge is that a small amount of PSE's Gaussian blur filter generally works better, with more control.
Carl
#4
By the way Eric, I'm sorry but I'd missed you mentioning this was a slide in your original post. Duh. Time to slow down and read things more carefully!
#5