Is the the screw thread of a filter regulated by some standard?

Question

Is the the screw thread of a filter regulated by some standard? I am talking about round filter. For example, is the ISO metric screw thread standard applicable?

Asked by uvts_cvs

Answer

I don't know the real answer, but in lieu of someone who does, a quick search tells me that apparently not, but that a 0.75mm thread pitch is used by "most Japanese photographic manufacturers today".

Answered by mattdm

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