If you mean Richard Lynch’s HPA3 tools try the forum on Retouchpro.com. The highlight mask just selects all the shadow area (masking out the highlights) The shadow area selects the inverse. (think I’ve got this the right way around – I always have to try it before i’m sure!)
Go to the forum Susan suggests … scroll down the screen until you find an area marked Tools. Click on Education and you will see the section you need to go to.
Learn how to rescue details, remove flyaways, add volume, and enhance the definition of hair in any photo. We break down every tool and technique in Photoshop to get picture-perfect hair, every time.
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