Reply to thread

OP: "... The second question is basically the same but this time the reference photo is a different picture..."

I interpret this to mean that you want to apply the same adjustments that you just developed for one image to a second image.   This is very easy to do.  One way is to simply have both images simultaneously open in PS and drag the set of adjustment layers over to the new image.   Obviously, there are many other approaches, as well.  For example, you could develop an action to insert the same set of adjustment layers in any image, etc. etc.

I can also think of a second interpretation to your 2nd question.  That is, what approach do you take to your question #1 if you don't have an unprocessed or SOOTC image that is exactly the same scene as your Image_A.   For example, perhaps you moved the camera or changed lenses between shots.   In such a case, my difference technique is essentially useless, and unfortunately, as far as I know, you are better off simply using your eyes and judgement to develop the appropriate set of adjustments.

Tom M