How do I highlight/increase visibility of a color?

[blickbox]

At work I photograph rocks/mountains with spray paint markings. Sometimes those markings are a little hard to see, so I would like to increase the visibility of them.

Usually, the photos are 95% greytones, and some red spray paint, so I guess it shouldn't be very hard to make the red color to stand out more.

It does not matter if the rest of the picture is slightly distorted, as long as it's easy to see the markings.

 

I have attached a sample photo. As you can see, another problem is that some areas have shaddows/darker areas - are there any simple techniques I can use to minimize the shaddows?

 

Thanks in advance!

[pdnnoob]

As long as the rocks are relatively gray like that, you can simply increase the color saturation to make the colored paint stand out. (Adjustments>Hue/Saturation or hotkey: ctrl+shift+u)

EDIT: The shadows are a bit more difficult, and how you go about reducing them depends on the purpose.

[blickbox]

Thanks, I already played around with the saturation, but It makes a bit too much changes to the rest of the picture - I only want the markings (red color) to be highlighted. Are there any other ways to achieve this?

[pdnnoob]

Ah I see. In that case, there is the Conditional Hue/Saturation plugin that worked pretty well when I tried it.

Set Hue range to about (280 to 20), Hue action to none, and Saturation adjustment to 200

[blickbox]

Thanks!! I'll try that! Looks like it's exactly what I need