Lomo Square front anamorphic - rotating problem

[Daniel Silwerfeldt]

Hi

I just recieved a Lomo Square Front Anamorphic 80mm which seems to be in very good shape..

I have one big problem...
The lens rotates when I turn the focus ring...
When I hold the lens I can tur the OCT-19 mount.. It seems to me that I can unscrew it... Should it be like this or is something really wrong?

Sorry if its a dumb question

Cheers

 

[Steffen Vala]

Presumably this is not the way it "should" be, but that depends on how much force you are applying in order to turn the mount. If it is very loose you need to fix it.

I have a couple handfuls of Lomo's and one of them had a similar issue.

 

[David C]

This may have been a lens that was converted to Oct-18 from Oct-19 mount. Oct-18 mounts was designed so that the entire lens rotates in the mount to focus.

Maybe someone did the conversion and it still turns (maybe it's supposed to)? Or it could be just loose, and you need to find some way to lock it down.

 

[Mike Prevette]

Dito what David C said. probably a bad oct-18 conversion.

 

[Daniel Silwerfeldt]

Thanks for all the answers.. I have taken a photo and it looks like there is a hole where I can fasten the mount.. I thought it was Hex wrench tool but its not...
Does anybody know what "tool" I should use and if I can fasten the mount tighten that "screw"?

 

[Anders Holck]

Does anybody know what "tool" I should use and if I can fasten the mount tighten that "screw"?

A hammer?

 

[David C]

I just got my 80mm in - looks to me like it's a tiny flathead screw. Be VERY careful with it, though... from what I've read, the screws that Lomo used back in the day are very fragile.

 

[Daniel Silwerfeldt]

Thanks for all the help and some jokes...
It was an allen wrench 1.3.

I can fasten it now Just have to get it 100% straight

Cheers

 

[Nick Gardner]

Any chance you want to rent me your oct-19 mount for a week?

Nick

 

[Dan Hudgins]

Ring

Ring

The ring behind the mount part with the set screw probably needs to be tightened, they should have a huge force on them to clamp the mount down.

I had to put great force on mine to get it off so I take that to mean that at the factory they used a foot wide wrench and two hands to tighten it.

Its very important for the anamorphic that it be level to he frame (film or sensor also).

The set screw is because any wiggle over time will make the ring loose, the set screws RUST into their holes though and can be hard to adjust later. I had to use penetrating oil (the purple kind) to get it out and change it to a new one as the holes in the Russian set screws may strip out.

The 35mm square front (well oval front?) is like that the ring needs to be very tight, any set screw can squeeze the focus parts and make it hard to focus, so the ring takes most of the role in holding the lens level.

You need to go to a good camera shop where they have the right lens wrench to adjust the ring tension, probably. It may SEEM tight, but it needs to be tight enough that you CANNOT rotate the lens mount part around.

Also be sure the grove is on the pin in the OCT-19 mount since it is possable to put the lens in and not have it on the pin.

Be sure to check the level with the lens on the camera, use a 90 degree square and the reflections on the front element of a window edge, they shoud align in the vertical.

It can be hard to get the lens level since when you tighten the ring the lens mount rotates, I guess that is what the set screws are added to stop. Anyway, the way to deal with that is to set the lens a bit off level, then as you tighten the ring the mount will rotate a small bit INTO alignment as it clamps harder. It may take several tries.

Some of those lenses that are sold as OCT-19 have BNCR backfocus maybe, since the Russians seem to have had some BNC with warnout rackover gibs so they decreased the flange to focal distance to compensate then rounded off the fractional part to a metric value. The backfocus on the set of Square front lenses did not match out camera, or each other. I had to adjust the mount parts thickness to get them to alingn with the camera and not a small amount. It seems the newer the lens the shorter the flange to focal length, I got a very old 1960's lens in brass mount and it had an adjustable focus mark, but even with that I needed to shorten the flange-to-focal by several thousandts.

The Lomo anamorphics can be quite sharp if they are in good alignment, but its hard to purchase one and have it work as is because they seem to not have a uniform interchangeability among various cameras.

Also they use plastic shims around the square lens elements, so unless you have special equipment, if you take it appart for cleaning, it will probably never be as sharp again once worked on because they just jam pastic shims in to get the anamorphic elements aligined, very Russian?