Gamer has been removed
The requirements for this achievement are to take at least one photo in every research group. There is an extensive list but you will have taken a photo of everything up to Fort Frolic if you have been thorough. So the research categories are quite simple;
Upon taking a photo of a Bouncer in Fort Frolic this achievement will pop for you, if not then take a photo of every different thing in that list that you come across.