Someone on another forum asked me about using PS's Shadow & Highlights, so I wrote this up. I figured some here might find it interesting or useful, thus a cut & paste.
If anyone else has any tips with S&H please list them. I use it a lot, but I can use any help I can get.
My tips for S&H:
Use it very early in the post processing. It tends to dull images, mucking with contrast and saturation, and you'll want to adjust them later so why do it twice?
For both Shadows and Highlights my default settings are Amount 10%, Tonal Width 30%, Radius 30. Color Correction 0, Midtone Contrast 0, both Clip setting at 0.01%. Though the defaults are so important I think these settings give a good starting point for most images. Set your options to these and click Save As Defaults at the bottom.
Until you get used to S&H use one or the other. Set one to Amount 0% and play with the other. I'll then click OK and then go right back in to use the other. Changing too much at once can be confusing.
I click Preview on and off A LOT.
And after clicking OK to save my S&H changes I'll hit Control-Z a few times, which will flip the image back and forth between Before and After. (I do this with Curves a lot, too.)
Color Correction will often not seem to do anything, so I will get my other settings to what I want, and then set CC at -100, wait for the preview to update, then set it over to +100 and now you'll see a definite change. It's not very finicky, so moving it 10 points will often not seem to have an effect.
Midtone Contrast is often required since S&H will tend to flatten the image and it will lose contrast. It will not completely fix the contrast, so don't go too strong. If you do you may find that contrast adjustments later in the workflow are too much - and it's not the contrast adjustment you made with Levels or Curves, but it's held over from S&H earlier in the workflow. If you're good with Curves then leave it at 0 and fix the contrast in Curves.
A large Radius will help avoid or eliminate haloes, whereas a small Radius will help bring out details almost like a weak sharpening. A small Radius will often need a larger Amount to balance, and vice versa.
Tonal Width is the brightness range being affected, so this can also have an effect on haloes. A larger range can help elminate or reduce the visibility of haloes.
When I do S&H I like to start with my defaults listed above, and first play with Tonal Range until I basically get the range I want. Then I play with Amount. Then Radius, then around in a circle tweaking them here and there.
After that tweaking I might play with Midtone Contrast, though more often I'll do Curves. But after adjusting MC I'll look back to see if I need to tweak some of the other numbers again. Once again, don't go too strong on Midtone Contrast since you'll probably play with adjusting contrast later anyway.
S&H tends to dull colors as well as contrast, so I'll play with Color Correction but I usually don't get much out of it. Instead, after S&H I'll often do some saturation tweaking with Image... Adjustments... Hue/Saturation.
I have to admit that I've never changed the Clip settings - I'm not exactly sure what they do, but have never felt the need to look into it, I guess.
