neuroanatomist said:fullstop said:retrofocus construction is only needed to bridge long focal flange distance due to mirrorbox in mirrorslappers.
Your understanding of lens design is woefully inadequate. A retrofocus design is needed when the focal length (sensor to rear nodal point) is longer than the flange focal distance (FFD). That's essentially the definition of retrofocus. Practically speaking the rear nodal point must be at least a few mm in front of the rear element for a non-retrofocal design. So, with an 18mm FFD, a non-retrofocal lens with a focal length of 24mm is theoretically barely possible, but practically difficult and would result in severe optical compromises (a >28mm FL is more likely). But...you've repeatedly stated that 18mm is too short an FFD for a 'really right mount'. A 22-24mm FFD means a ~35mm or longer focal with a non-retrofocal design.
Of course, there's another way to use a non-retrofocal design with, for example, a 24-xx zoom and an FFD in the 18-24mm range. Simply use a hollow tube at the back to the lens to provide some additional distance between the sensor and the rear element. Perhaps you've seen that implementation somewhere, hmmmm? :
Once again, facts and reality demonstrate the fallacy of your opinions and statements.
I love a good zing.
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