Can anyone comment on why 40mm lenses seem to be so short and simple? I don't know of many, but the M-Rokkor and the recentish Canon 40mm EF lens are downright tiny. Same with the 40mm Voigtlander for E-mount, which is pushing the limits of pancake thinness. Then there's their super small 40mm 1.4...
I know that 43.5mm (ish, somewhere around there) is said to be the true standard focal length, whatever that means, rather than 50mm. I.e. the closest thing to human eyesight magnification and spacial relationships on the z-axis...maybe only for 135 film dimensions, I don't know. Though the master filmmaker, Yasujiro Ozu, thought 50mm on vertically fed 35mm film was the most comparable focal length to human eyesight, and thus the least distracting focal length. Anyway, what I'm trying to ask is whether or not the 40mm focal length is something special, like the simplest of all lengths for which to design. 35mm seems preposterously complex in comparison, but that could be because all the tech is focused there because of people's love for that length.
Thanks.