Technique / Discuss

Tolka Rover    says:

I sometimes use this technique to create a photo that is partially colour and partially black and white. It is not as general as the cut-out technique because the colour you are selecting cannot appear anywhere else in the photo, but it is a lot easier because it does not require skilled mouse-work to "draw" regions.

This is very simple to do, and perhaps is already well known.

I do this in GIMP, but I assume there are similar capabilities in Photoshop.

(1) Open your photograph in GIMP

Decide what primary and secondary colours you want to keep and which you want to convert to black and white. Say for example you want to keep the blue sky as the only colour then you will keep BLUE and CYAN, and desaturate GREEN, YELLOW, RED, and MAGENTA.

(2) Select from the menu: "Layer -> Colors -> Hue-Saturation ...". Click the radio button for GREEN and move the Saturation slider all the way to the left until it reads -100. Then click the YELLOW radio button and move the Saturation slider to the left in the same way. Do this for GREEN and YELLOW too.

(3) If you want your blue to be even stronger you can click in turn on the BLUE and CYAN radio button and move the saturation slider a little to the right. But check the preview picture, because sometimes making these colours too saturated will cause undesirable effects if you have a little of the BLUE and CYAN scattered elsewhere in the photograph.

Here is an example that picked out the BLUE and CYAN of the sky:


Here is another example that picked out the RED:

Posted at 6:36PM, 10 April 2006 PST ( permalink )