noun: Someone who counts pixels, measures the performance of cameras and lenses on graphs and does other trivial tests that have no real importance with reality. They are a person who puts WAYYYYY too much importance on the minutest details which in the end have zero bearing on the resultant photograph. Though this is specific to photography it's concept would apply to any field where an instrument is being used.

When someone thinks they are the main character of their life. Usually comes with a side of individuality complex, quirky style and a self centered point of view.