Can anyone speak to the supposed problem with the lens cone made for the 135mm f5.6 Apo-Sironar-S for the Horseman 612? I’ve found only a few references to this without much additional info and am trying to confirm if it is true and also determine if it was redesigned/resolved after a certain serial number. If anyone knows any of this for certain please let me know. Thanks very much.
Edit: I forgot to state the actual problem
Apparently Horseman made the lens cone too narrow which causes the lens to vignette, progressively worse at closer focusing distances. I guess there was rumor that they’d remedy it with a design update but I haven’t found anything that confirms that happened or if it did, what serial number the corrected cones begin at.
Edit: I forgot to state the actual problem

Apparently Horseman made the lens cone too narrow which causes the lens to vignette, progressively worse at closer focusing distances. I guess there was rumor that they’d remedy it with a design update but I haven’t found anything that confirms that happened or if it did, what serial number the corrected cones begin at.
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