We recommend that you only use Photo Enhancement on the photographs you upload, which have not had any post production work. Its ideal for amateurs who want a little optimisation of their photography.
Our software has been fine-tuned to work with photographs specifically, and it can cause some unexpected changes to artwork, be it line art, bitmap or vector images, scans of paintings etc. It can also over-enhance any post production work that has already been done.
You can find out more about the specifics of Photo Enhancement here.