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Anybody seen one of these ?
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PostPosted: Tue Mar 13, 2018 11:19 pm    Post subject: Anybody seen one of these ? Reply with quote

This was posted in a MF lens group. The owner didn't know how to operate the aperture and the focus ring wont move. Anybody here think that there is something very strange about this lens

(Spiratone 35mm, f2.Cool



PostPosted: Tue Mar 13, 2018 11:21 pm    Post subject: Reply with quote

It's a Sankor, a common lens. A decent performer for it's age.


PostPosted: Tue Mar 13, 2018 11:25 pm    Post subject: Reply with quote

Its just that I have never seen two fully marked aperture rings in a preset before and there appear to be two dof scales !


PostPosted: Tue Mar 13, 2018 11:54 pm    Post subject: Reply with quote

hemeterfilms wrote:
Its just that I have never seen two fully marked aperture rings in a preset before and there appear to be two dof scales !


Almost certainly it's a pre-set lens, one aperture ring is used to set the minimum aperture required, it'll be detented in some way or another, the other aperture ring will be free turning, often mistakenly described as "stepless", though I suppose it can be considered as such.

To use such a lens, the required aperture is pre-set on the one ring, the required shutter speed set, the lens then focussed at full aperture, then the "stepless" ring is used to reduce the aperture to the taking value without having to remove the camera from the eye. Sounds clumsy by today's standards, but at the time it was leading technology! Remember, no TTL metering in those days, EVERYTHING was manual!

I'm not seeing two DOF scales, just the one either side of the central index plus an infra-red offset mark, all "normal" stuff for the age.

Can't help with the stuck focussing ... it's probably just stuck Wink


PostPosted: Wed Mar 14, 2018 4:05 am    Post subject: Re: Anybody seen one of these ? Reply with quote

hemeterfilms wrote:
This was posted in a MF lens group. The owner didn't know how to operate the aperture and the focus ring wont move. Anybody here think that there is something very strange about this lens

(Spiratone 35mm, f2.Cool



Yes, looks like a normal 2 ring preset lens, one ring is the preset ring, and the other ring is the aperture ring,
If you set the preset ring to the smallest opening f16, the aperture ring will move freely from wide open f2.8 to f16, change the preset to f8, and the aperture ring will freely move between wide open f2.8 and f8, set it to 2.8 and the other ring won't move. So as the lens sits in the picture, one of the rings should move easily between f2.8 and f4, if it doesn't, it may need service.
Takumar 50/4 1:1 Macro set to f4(the other dots[Blue, Yellow, Orange, Red] is the effective aperture depending on the focus distance/magnification) on this lens the preset ring is the lower ring, on a helios 44, it's the upper ring.


Odd that the focus ring is stuck, could be the grease has thickened up, a lens tech should be able to get it to operate properly.


PostPosted: Wed Mar 14, 2018 2:46 pm    Post subject: Reply with quote

Ditto re Sankor.
I have one on my workbench right now.

There are quite a few Japanese presets with dual scales.


PostPosted: Wed Mar 14, 2018 3:47 pm    Post subject: Reply with quote

It's one dof scale they have just angled the marks so the f stop numbers don't impinge on each other.