Well, you are correct that checking your photo refrences is always the way to go. This site clearly states however that they are merely representing
"standardized" zimmerit patterns and that "contradictions abound". There is even photo evidence of SP's having zimmerit applied which was not the norm.
A site like this is handy for the less learned(like myself) and you don't have to go chasing all over the internet for refrences. If your emulating a photo
however,that makes things a lot simpler.