How to replace a (range of ) color with transparency?

[MrAnalogy Profile]

I'm trying to replace the green background behind a woman's hair (it was shot against a green screen) with transparency. I'd even settle for white.

I tried using the smart brush but it leaves bits of her hair that are greenish (or have a green edge). There's no other green in the photo so I'm thinking that a color replacement might work.

Here's the photo:
http://www.bungalowsoftware.com/downloa ... C-ipad.JPG

any suggestions?

-MrAnalogy

[admin]

This sort of picture should be a breeze with the Soft Edge finder. You'll need to use a nice large brush to avoid the centre circle going over her hair while managing to cover all of it. Occasionally you'll need to go back round the hair for a second pass. Another tip is to use the remove halo button (the third button on the underlay layer). I've attached an example of what I managed to achieve with just a couple of brush strokes in the composite tool.