Scale of manufacture is irrelevant. Back to topic, there are various helicals available that are marked for focus distance based on extension. Infinity calibration is done by the user by setting up the camera to infinity based on their design or needs with the helical at min. extension. These are easily found via the Chinese distributors mentioned or larger manufacturers for specific lenses they make. Hacks from cheap helicals from old lenses are also workable with more work/risk.
OP should mention what lens.
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