removing grey background

[FrEaKmAn]

Hello,

this is the example image
http://shrani.si/f/r/AA/2mAQAStH/stran011611.jpg

what I want is that I somehow make it lighter, but obtain black letters. The problem is that when I want to print it, I get grey background which is really annoying.. is it possible to somehow get better printing results?

[Damo77]

It's a pretty simple matter of Levels. Open Levels (Ctrl-L) and choose the white dropper and click on the paper to make it white. Then move the shadow slider in enough to keep the text blackish.

This might introduce some nasty colour artefacts, so you could probably then open Hue/Saturation (Ctrl-U) and partially desaturate.

This is the very quick and dirty solution, of course.

[FrEaKmAn]

Originally Posted by Damo77

It's a pretty simple matter of Levels. Open Levels (Ctrl-L) and choose the white dropper and click on the paper to make it white. Then move the shadow slider in enough to keep the text blackish.

This might introduce some nasty colour artefacts, so you could probably then open Hue/Saturation (Ctrl-U) and partially desaturate.

This is the very quick and dirty solution, of course.

can you show any final examples. I'm trying to find the best settings, but if I make background totally white, then I lose most of the text...

[Dave.Cox]

Try this. Should be good enough to be readable.

[mistermonday]

I converted the image to LAB color mode and then applied the L channel to the image. Did a Curve adjust to separate the text from the black gunge (there was already quite a separation between them). Then used the Dodge and Burn tools to darken the text and lighten the smudgy areas. Attached is a quick sample (did not ay much attention to detail). You could get it completely black & white and clean by spending a little more time.
Regards, Murray

[DCobb]

This is my try.

dc

[FrEaKmAn]

Originally Posted by mistermonday

I converted the image to LAB color mode and then applied the L channel to the image. Did a Curve adjust to separate the text from the black gunge (there was already quite a separation between them). Then used the Dodge and Burn tools to darken the text and lighten the smudgy areas. Attached is a quick sample (did not ay much attention to detail). You could get it completely black & white and clean by spending a little more time.
Regards, Murray

your example looks really good. I have few more question which might sound stupid...

- How do I apply L channel to the image?
- Any more details for curve settings (input, output)

and thanks again to all that replied...

[Gary Richardson]

This is about as good as I could get it.

Quick levels adjustment layer, then a little dodging and burning.

[FrEaKmAn]

Gary, yours look good also, get I get more info about level adjustment layer, which settings you used? I have 20 more pages to change so I would like to know how to do it...

[mistermonday]

After you convert to LAB, select the L channel in the Channel Palette and from the the little trianlge menu select New Channel. When the dialog box comes up select New from the Document window. This will create a new document from the L channel. Next go Image>Mode>Grayscale to convert this Multichannel document to a grayscale document.
(BTW, I used LAB instead of desaturating the RGB image because it yielded a better contrast grayscale image).
Next apply a curve or curve adj layer to separe the shades of gray. Ctrl click on the darkest spot you can find to set one point and ctrl click on a neutral gray area in the background to set the other point (see screen shot 1).
Move the dark point down and the lighter point up to blow add contrast. See screenshot 2.
Now you are into cleanup mode. Use the Dodge tool set to Hoighlights and brush over the gray background to turn it white. Use the burn tool set to shadows to darken the writing. You can reduce the brush opacity if you need finer control.
Regards, Murray