As a scientist, I process digital images all day. Although I have access to powerful image editing tools such as Photoshop I have to be careful not to manipulate data unfairly. Thus, while skilled in post processing, I can't be too creative with it in my profession.

Digital photography, on the other hand, is not a science; it's an art. The purpose isn't communicating complex data but merely creating something beautiful. And, quite frankly, it's a great way to get creative after a long day at work ;^)