OK, on with my question....
I create PDF files from old scanned books and reference catalogs. These books often have yellowed pages, or darkened with age. Do you have tips on how to best improve the look of the pages?
Over the past few years I've used a tool called Able Batch Converter. I originally purchased it because it has a "deskew" command. It too is script based. Everything XnConvert does, Able does as well, and then some. But, the graphical interface on XnConverter is so much better.
I have mastered, to a certain extent, Able Batch Converter, that I can eventually get a scanned book looking really nice. But, I don't quite know what I'm doing because I'm an engineer not a trained graphics designer. It's difficult to translate my current scripts to XnConverter.
I typically am facing these aged books plus lack of contrast from my scanners. It was just last year that I experimented a bit further and found that Gamma modifications often helped more than contrast control.
I hope to find a few tricks that I can use with XnConvert just like I have done with Able. Each document is a little different so I've made a couple of dozen different scripts.
USUALLY, when I convert one of these old books to a grayscale document, my scripts contain:
- "White Balance" (no controls available with that command)
Gamma correct downward
A slight increase in brightness to offset the Gamma correct
My script that processed the attached image looked like this:
- Gammasat 0.17
Levels Black point = 62, White point = 218
HLS. Hue = 0, Lightness = Lightness = 2, Saturation = -6
While writing this post, I did a bit of research on the web and found advice that said to play with the levels in the histogram. These XnConvert commands play with levels so I know I'm on the right track with it all.
I'm really happy with the outcomes so far, but am looking for any advice other may have, especially if you've done them with XnConvert.