Photoshop is a very powerful tool. You can do almost anything to an image. BUT SHOULD YOU? Knowing when enough is enough is a vital skill, whether in framing the subject or adjusting the tones in an image. Knowing the difference between magnificent and cartoonish, subtle and boring takes skill, experience and a good eye.
Some claim the good eye is inherent, I think it is developed, through looking at fine images.
Some aspects of the fine image can be garnered from magazine and book quality reproductions while others require seeing original prints, and without glass between you if possible. Workshop teachers typically bring bare prints to show and this is a fantastic opportunity. If you don't spend 4X as much time going over the instructors prints as anyone else in the workshop, you aren't getting the most out of the workshop. Ask to view the prints at lunch time - so what if you starve. Find out if you can have a private look through at the end of the day. Far more than skill or talent, instructors admire enthusiasm and a willingness to learn.