[vonBaloney]

Tomioka Yashinon 60mm 2.8 macro preset -- the Mamiya/Sekor lens with the same specs is the same lens I'm told. Just received this, and it has an odd property. I'm wondering if anyone else is familiar with it and can tell me if it is normal behavior. The aperture is preset and has two rings, but the focus seems like it has a preset type mechanism as well. Like any 1:1 macro, it has a long focus throw and the lens extends quite a bit, with markers for the various levels of magnification. Once you get to 1:2 and below moving towards 1:1 it has a hitch in the focus -- it becomes more dampened. It acts like a stop -- if you aren't applying much pressure you'll find it easy to stop exactly on this point. If the lens has been in the un-expanded position (focused on infinity) then this hitch/stop will be at exactly the 2.0 mark, but if you then turn it to say 1.5 and then turn back in the other direction but not too far (say back to 2.0) and then reverse direction again you'll hit the stop at 1.5 -- the farthest point you previously reached. In other words at close magnifications, it acts as a limiter that indicates the point of greatest magnification you had previously reached. It gets "reset" when you turn the ring more than a half-turn or so -- you can feel the inner ring or whatever it is pulling back in the other direction. I've never seen any lens do this, but this is a rare and special lens. But is it on purpose (it does seem potentially useful) or is it broken and whatever is floating around in there shouldn't be doing that?

[babajoof]

Hi VonBaloney. I have the Macro Yashinon version. I just got it out and I am not experiencing any inconsistencies with the focus ring. It seems smooth focusing throughout the entire range, from infinity down to 1:1.

[vonBaloney]

Hi VonBaloney. I have the Macro Yashinon version. I just got it out and I am not experiencing any inconsistencies with the focus ring. It seems smooth focusing throughout the entire range, from infinity down to 1:1.

Thank you for checking.

Yeah, must have a missing screw or something sheared off inside, although if the inner part that seems to be floating around were clamped down, it seems like it would just stop the focus ring cold mid-range. It is strange though, because even though it has that hitch, it isn't scraping and it doesn't have heavy resistance -- it doesn't really seem broken and the condition otherwise is almost new. But clearly something in there is being pushed back and forth with the action of the ring. I probably don't want to attempt disassembly because I'll probably make it worse it does have a warranty from the dealer.

Oh well -- looks like I'll be returning it. Such a cool lens.

[ducdao]

Thank you for checking.

Yeah, must have a missing screw or something sheared off inside, although if the inner part that seems to be floating around were clamped down, it seems like it would just stop the focus ring cold mid-range. It is strange though, because even though it has that hitch, it isn't scraping and it doesn't have heavy resistance -- it doesn't really seem broken and the condition otherwise is almost new. But clearly something in there is being pushed back and forth with the action of the ring. I probably don't want to attempt disassembly because I'll probably make it worse it does have a warranty from the dealer.

Oh well -- looks like I'll be returning it. Such a cool lens.

I have two copies of the Mamiya Sekor 60/2.8 and both work as intended. Your copy looks like it was opened by previous owner and he/she did not properly assemble it back.

[vonBaloney]

Thank you also. It's going back...