How to make a color photo black and white, with one color accented.
Here is the photo I'm starting with.
It was a stock photo supplied to me by dropbox an online file share service.
Isn't he cute?
Create a new layer on top of the "background" layer.
<--This is the button for it...
select the "background" layer.
Use the lasso tool to select something that should be colored.
OR, you can use Select>Color Range... and use the dropper to select a range of a specific color, I chose red.
This selects everything EXCEPT for what you want to change color.
Select the new layer created in step 1.
Use the paintbrush tool and make everything black.
Set the blending mode for the layer to Hue.
<---This is what it looks like.
Link to tutorial: www.instructables.com
Although, I didn't really need the tutorial to do this.