>>3533884>lol, please find me a quote on 'scientific definition on standard lens'. One will do.Focal length = length of sensor diagonal
>Standard lens = 50mm. Always was, always will be.Nah. That's a historical coincidence that many 35mm cameras came with 50mm lenses. The inventor of the format just happened to use a 50mm cine lens cause that's what he had laying around and it was close enough.
Standard lenses in pretty much all other formats (6x6, 6x7, 4x5", etc.) are closer to 42mm (equivalent) than to 50mm (equivalent).
Also many fixed lens rangefinders came with 40-43mm lenses.
If popularity of the "available lens closest to normal" is your argument for standard, then 28mm is standard for phones, and 42mm for all formats except 35mm.