Help with retouching a very old photo

+1 more for a tutorial. Your conversion is really beautiful.

When I get around to putting together a tutorial, I will start a new thread. Bigbitt, sorry if I hijacked your thread here - If you can post a better scan of your aged newspaper photo, I will be happy to take a whack at it.

Thanks for the encouragement to do a tutorial folks - it will, unfortunately, involve a little geekitude so that you understand what FFT is, what it can and can;t do, etc. Hopefully it will make the point without putting everyone to sleep.

Kirk

NIH Image was originally a Mac-only image processing software but got ported over to Windows as "Scion" and is still available at:
http://www.scioncorp.c​om/pages/scion_image_w​indows.htm

I recall doing FFT work with it years ago in my "physics" days. As I recall it was NOT Java based and was very well documented....hopefull​y it remains as such....but it might be worth a try.

Cool. I figured someone had ported that to PC before the Java version came out. I have been a Mac person since my sweet Mac SE20 so I never really looked too hard for the PC version.

Here is a first attempt at getting this old image retouched a bit. The screen pattern is not very well defined, maybe due to the original quality of the image, as well as the low contrast on the scan (yellowed paper, light ink). The screen pattern shows in the FFT, but there are frequency components of the screen that are tougher to isolate. I went gentle on the removal of the screen to preserve what little detail in the photo remained. After removing the screen pattern, I used a gentle pass of Neat Image to filter some of the more random noise. I sharpened and did a curve move to get better contrast. I sacrificed some shadow detail in the background at that point. Finally, I converted the image back to RGB and colorized it with a sepia-esque tone. It could be better. A flatter, higher contrast scanned original would improve the result as well.

Original:

Hopefully you will link the new thread from here.......

Absolutely incredible technique. I've downloaded Fiji and I'm learning about this now. It's amazing that an image can be recovered so effectively.

kirkt wrote in post #5793303
Bigbitt - If you can post a better original, flattened under glass, etc. per Mike_D, you might be able to use a couple of different techniques. Here is an example where a regular pattern (a screen pattern) was removed with a filtering technique called Fast Fourier Transform filtering, and then that image is manipulated to final. I used Neat Image to remove the noise after FFT treatment, but I am sure there are many other ways. If you use basic blurring techniques, or noise removal techniques, on the entire image to remove the regular screen pattern, you will essentially be losing all of the detail at the screen resolution (sort of what Jon is referring to). With FFT, you can target the frequency of the regular pattern, remove that component of the image, and retain more detail for sharpening, etc.

If the screen frequency is 65 LPI, you want to scan the original at least twice that frequency to avoid aliasing the screen data.

Post a better original and I'll give it a shot. Here are a couple of links to my smugmug page with some FFT examples:

http://kirkt.smugmug.c​om …1871_49ury#4478​2280_FMroZ

http://kirkt.smugmug.c​om …8997_fbkQ7#4570​0479_EV8Rz

Kirk