"what degree is "adjusting" the image acceptable?" as much as you damn well want. You could spend 40 hors doing some sick adjustments to an image, and it will look antirely natural, or you might be in the right place at the right time, and get a photo that looks impossible, do no post work on it, and it looks completely fake. anyone tells you something is unacceptable, point out to the that they neglected to remove the tomcat from their rectum when they woke up this morning.