Two questions about recorded digital photo files:\n1. Filename for photos : Canon with IMGxxx, Panasonic with Pxxx, Casio\nwith CIMGxxx, Sony with DSCxxx. What about others such as Pentax,\nNikon, Kodak, Olympus, Fuji, etc. ?\nCould this name be changed prior to picture taken? or is this feature\nbuilt-in the camera that the photos will always have that file name,\nplus the numbers that follow?\n2. Why there are so many file extension for the RAW files? I heard\ndifferent extension name for different brand camera, and even\ndifferent name for same camera with different model. Example : Nikon\nwith .NEF extension. With this different extension name, does this\nmean that the data must be read by a special softwares (as the one\nthat comes with the camera or special PSP or Photoshop) ? What\nhappens if you rename the file extension on purpose, can it be read by\nPSP or photoshop? or it will become corrupt? Is there a common file\nextension name, such as .RAW?\nThanks for info.