Cleaning Yellow Pages

[onmypace00]

I've tried to clean manga with yellow pages, but I can't do them right. They just remain yellow! Are there any ways to clean manga with yellow pages?

When I upload the picture to the internet it seems to be black-white like I want it to be (spoiler tag), but the original is yellow-ish. And when I saved the picture it's still yellow.

Spoiler

 

[zidane]

Option a) Image -> Adjustments -> Desaturate. Option b) Image -> Mode -> Grayscale.

 

[Gradonil_Ral]

Option c) Image -> Adjustments -> Gradient Map (a black&white gradient).

Personally, I think that changing the mode to grayscale is the most "neutral" option - desaturate tends to lighten up the lighter colors and gradient map can sometimes make the darker ones a bit too dark. Then again... you can adjust that by editing the gradient.

The only problem with changing the mode to grayscale is that it will turn the entire file to grayscale, not just the selected layer. So don't use it on files where you wanna keep something in color.