Ckw From UK - England, joined Aug 2010, 660 posts, RR: 17 Reply 4, posted (10 years 4 months 4 weeks 3 hours ago) and read 827 times:
You can't do what you want as you describe it Phil (if only!).
But there is a way of working so that you can achieve this to some extent, commonly used by graphics professionals.
The secret is to create a new layer for each and every process you apply to the picture. For example, you can make a duplicate layer of the image and apply sharpening. Another layer may incorporate colour adjustments.
Each layer can be edited and modifed independent of other layers, and even better, you can control how the multiple layers are eventually combined (eg. you can "fade" the effect of a particular layer).
Working in multiple layers is of course far more complex than working on a single layer, but the only way of achieving the control you want.