What has to be done, when one has just bought this mirrorlens, and discovers, that it doesn't fit on your camera...?

(or a MTO-11CA ( russentonne ))


Parts of this text and some pic's

borrowed from

Copyright 2001  
Leonard Flanagan



Should you follow me in these steps, I must point out now, that you will be doing so on your own account. I cannot be held resposible for damage.

Indeed, it's imaginable to ask yourself

"What good is there in dissassembling a totally fine working lens"?

After all, they are precision crafted... (at least that is what I thought).

In this tuorial, I won't tell you how to disassemble glass elements of mirrors. Yes, these Russian lenses are robust and quite hefty, so they will take this abuse graceiously.

This image illustrates the problem quite well. In fact, with my Nikon D70, the prob is even greater, It won't fit at all.

A solution is to use an extender, but that results into light-loss and degrading image quality. And there simply are moments, that we ONLY NEED 500mm.

So how about a macro ring?

Yes, an 11mm one would solve everything, but to use it, we need to adjust the infinity setting on the lens, to achieve proper focus at long distances.

In my case, an old and therefore cheap Panagor ring set was the right choice. It came withe the desired 11mm ring, and the other rings proved to be quite useful for macro photography.

The automatic exposure meter won't work anymore of course, due to lack of lens electronics, but I am studiying on that one. I may come up with a solution, maybe one of you readers???


It's time to start!!!!

Inside the Rubinars, we will need to move (adjust) a notch, to allow infinity "to be infinity indeed".


  De " Russentonne ", de MTO-11CA

This one is the easiest, just unscrew this screw...

It might be a good idea to put someting into the hole, to prevent dust, (or little animals such as ants...) from entering, and inviting others to come on in and have a good time...

That's all here, just be aware that there is NO infinity stop anymore, so don't turn too far!



 De Rubinar 500 5.8

A bit harder, but still easy (IMHO).

First remove the rubber grip, by sliding it gently over the barrel. The ring is stretched around it, so "strech it a little"

Then you will see these 3 tiny screws...

Unscrew these screws a bit, all three evenly. They are also used for centering the focus ring!

If the screws are loosened enough, the focus ring can be pulled off in forward direction.

This is how it should look after removing the focusing ring.

I myself have not removed the alu-stop-ring, I just loosened it a bit, and turned it, so that I achieved proper infinity setting, whilst losing some of the close focus ability.

(Which is not the best characteristic of this lens, anyway).



There also is a 1000mm Rubinar Mirror.

It should NOT be modified as mentioned above! It is constructed using ball-bearings, which might fall out during this excercise.


Left is the 1000mm Rubinar,          At the right the MTO..