Black and White with a pop of color

It's easier in PS or PS elements but you can do it using the dodge and burn plug-in supplied with Aperture - just paint in the areas that you would like to desaturate.

RB

There was a tutorial that helped me do this that I saw on the Aperture 2 Quick Tips podcast which is in the iTMS. The tutorial was showing how to enhance colors using the "Color" controls: click on the little square next to a specific color, then select a color in the image to define it, then use the sliders to enhance that color. That was the basic idea. But I also realised that you can use the sliders to reduce the color to nothing (monochrome) fairly easily too.

I just put this up as an example: http://gallery.me.com/extensions1#100064/DSC_4737&bgcolor=black

That will only work if the color or colors you want to desaturate are of a limited range and not in the same range of the color that you want to keep.

RB

Agree. But its a start and does not require any additional software.