How to remove vertical lines (banding) from a scanned b&w image?

[The Candiru]

I have an image that was scanned years ago with a mediocre scanner (see attached). I'm having trouble removing the vertical lines.

This forum post talks about removing color banding, but my image is effectively monochromatic. Or at least I plan on removing all saturation eventually.

This one talks about a creating a duplicate layer in color blending mode, and applying a Gaussian blur. But I'm working with CS6, and this layer mode is unavailable to me.

Any help would be appreciated! Thanks in advance!

[Test Screen Name]

These lines look like moiré, which you get when rescanning material from books, magazines etc. and which is very hard to avoid with any scanner, because it's caused by the dot pattern used in the original printing. So search for info on moiré, there is a lot of discussion of this in Photoshop, though it's not easy to fix.

[josephlavine]

The concept from the second post you reference can still be used.  The idea is to see whether the banding is primarily in one of the channels, and not all three. 

Go to Channels and click on each one to see where the issue exists.  If it's just part of one channel, have that one selected and apply a  gaussian blur.

I hope this helps

[Barbara Ash · Accepted solution]

This is a difficult photo and no matter what you do it will be tedious and far from perfect.

Make 2 duplicates of the image: copy 1 and copy 2.

In copy 1, Filter > Blur > Gaussian Blur, somewhere between 1 - 10, depending on the resolution of the image. The idea is to minimize the lighter streaks, even though the image will be degraded. I copied the image from your post and used 10 because the image is low res and also because the banding is so extreme.

Go back to the original image. Image > Apply Image. Apply copy 1 using Darken mode.

Now go to copy 2, and use a Curve to darken the highlights.

Still in copy 2, Filter > Noise > Dust and Scratches. Use the same radius that you used earlier for the Gaussian Blur.

Go back to the original image. Image > Apply Image. Apply copy 2 in Lighten mode.

Select small areas one at a time and use content aware fill and use the Patch tool to remove the more prominent streaks in the face.

With the original on the bottom layer and the edited version on top, you could add a layer mask and hide areas like the eyes to bring back some sharpness.

You would end up with something like this:

Desaturating the image would help.

[The Candiru]

Yep, I was afraid this was going to be the case - going spot-by-spot and patching/blending, then revealing the original layer underneath in spots to preserve the underlying details. Thanks so much for the step-by-step!

[JaniceCA]

Thank you, guys. It worked:)