Recovering highlights for photo restoration
This is only possible if the original image has tone or texture in the highlights to be recovered. With photo restoration the highlights are the important part. It’s best not have highlights that are completely white as when printed they look very disappointing as plain white paper. What we want to achieve is a subtle texture and tone.
For example If an image if very white in the sky, to correct it one method might be to use apply image. This mixes the same image on top of and combines the tones to multiply them. In effect what we get is a darker image, used in conjunction with a layer mask to hold back the areas we don’t want darkened this technique can be used to good effect in photo restoration to recover the highlights.

Photo restoration apply image