Here's my first offering to you all - using selective colour to change hair colour.
I hope the pics uploaded ok, there should be two examples. The first jpg is from a thread on Model Mayhem, I can't remember which one exactly, the second is from the Chris Orwig Portrait Retouching Essentials series which I've found very good for a beginner like me. I've been into retouching for a couple of months and am trying to build up a few basic techniques as I go along. On these pics I went backwards and forwards between the neutral and black modes in selective colour and moved each colour slider along until I found colours I liked for each model.
Once the colour was in place on each head I went through the blending modes and found fascinating variations in colour but You can play with these things all day so in the end I left each blend on normal and lept the opacity of each at 50% to keep it looking a bit more natural. I added a black layer mask and painted the new hair colour back in, and at a lower opacity around the edges. I know my brushing isn't very good and the technique is a simple one but it's always exciting to learn something new. Next on the list is to learn how to mask hair, any suggestions?
Here's a third example, photo also from Chris Orwig Portrait Retouching Essentials. This time I added a levels layer and a curves layer on top of the selective colour layer, to adjust the colour cast and brighten the pic up. I was trying to get eh hair colour from brunette to blonde and somehow ended up making it a fetching purple! It's amazing how you can end up with something totally unexpected when you experiment. Still, I think it suits her.