Can anybody explain frequency separation in Photoshop? It's generally used for retouching faces without affecting colour underneath.
I saw it demonstrated at a seminar by photographer Christian Fletcher. http://www.christianfletcher.com.au/photographs/ I thought I could use it to put sharpening on another layer and indeed this works. I did this by deleting the blurred "Low" layer and applying sharpening on the frequency separation "Top" layer. This works and you can turn down the opacity of the sharpening or deep etch it. However the top layer is already sharpened by the process, resulting in over-sharpening if I use my usual smart sharpen and then unsharp mask. I gather this is to counteract the usual blurring? The process doesn't work if you don't blur the "Low" layer. If I knew what sort of sharpening the process applies perhaps I could compensate better. I'll send this to the list too.
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