Originally posted by hinman The komine copy of the vivitar zoom looks so much like the Tokina copy. In appearance, v2 from Tokina and v3 from Komine almost look identical, but there is the red line in lens' front distinguishing it from v1 and v2.
Actually, to me, the biggest visual difference between V.2 and V.3 (both V.3a and V.3b) is the DOF/IR markings on the barrels. In V.3, there is a white straight line for focus distance, a curved red line for IR focus distance, and several green lines for DOF range. In V.2, the multiple green DOF lines are absent, making for a "cleaner" (or less "busy") appearance.
As for the red line around the objective end of the lens, it is interesting that it is present in V.3b (Ka), but is absent in V.3a (K) - the two V.3 models are otherwise marked very similarly (except, of course, for the "A" button). Most of the newer versions (V.3b, V.4a, V.5, and V.6) have the red circle, while the older ones (V.1, V.2, V.3a) do not. (The gold V.4b lens is marked with black on gold and gold on black, with no other colors.)