Serious photographers who host their pictures at 500px will soon get to profit from their skills -- if not quite in they way they'd expect. The company has just unveiled Prime, a licensing store that's theoretically more lucrative than many cut-rate stock photo sites. Every image will carry a minimum $250 license fee, and photos will be ranked based on community reactions. A frequently shared photo may stand out from the pack, for instance. There's only one catch. 500px is only giving sellers a 30 percent commission, regardless of the licensing terms -- that's a considerably smaller cut than some pros are used to, and might not be as rewarding as selling the work directly to customers. Prime may be difficult to justify for full-time shutterbugs, then, but it could prove useful to hobbyists who'd like to earn some extra cash with minimal effort.