Dual format (6x4.5, 6x6) Mamiya Six Model V Folding RF - switch question

[brianssparetime]

I recently picked up an old folding Mamiya Six rangefinder Model V that can support both 645 and 6x6 formats.

I’ve read up on a few other posts about this camera, but I can’t quite figure out how the two switches on the back of my camera work. One is labeled on-off, and the other has markings for 12 and 16.

It’s clear to that this Model V has “automatic” advance since I have only a single red window (meaning that after initial alignment through the window, the camera knows when to stop advancing).

I've read that the 12/16 switch unlocks the advance, but what does the on/off switch do?

Can someone please explain how each switch functions?

What is the correct procedure for switching formats (aside from flipping the petals inside and adjusting the viewfinder using the tab on the front)? How does one advance film correctly? I’m a little hesitant to discover by button mashing…

Any help much appreciated, and thanks in advance!

Other posts for reference:

Two windows vs one, how to flip viewfinder between modes:
https://www.rangefinderforum.com/forums/showthread.php?threadid=169838

Distinguishing K from Model V, two windows vs one:
https://www.rangefinderforum.com/forums/showthread.php?t=153934

Thread doesn’t answer question about buttons:
https://www.photrio.com/forum/threads/mamiya-6-folder.177890/

My camera has a different button arrangement:
https://www.photrio.com/forum/threads/mamiya-six-folding-advance-mechanism.147030/
https://www.photrio.com/forum/threads/mamiya-6-folder.177890/
https://www.120folder.com/mamiya_six.htm

 

[shawn]

As I recall the on/off really just unlocks the ability to change from 16 to 12 exposure. It moves the bar out of the way so you can slide the exposure switch vertically between the two options.

Shawn

 

[brianssparetime]

Thank - when I slide the on/off switch, I can see something protrude into the 12/16 switch.

But the 12/16 switch I think only goes leftward (following the arrow, in the same axis as the on/off), not up down. It feels spring loaded to return to the right, and moves identically whether the on off is on or off.

From what I read, I think the 12/16 switch is related to advancing film, but maybe I'm missing how it moves or whether it's involved in changing formats....

 

[brianssparetime]

Here's the solution (credit to /u/BigFujica690 on Reddit on my thread there: https://www.reddit.com/r/AnalogComm...iya_six_model_v_multiformat_how_do_these_two/)

The frame counter must be advanced to between 12 and 1 (or between 16 and 1 on the 645 part of it), AND the switch must be in the off position.

Then, the 12/16 lever can be pushed all the way left, and then, and only then, can be it be pushed up or downwards, after which it clicks back to the right.

The on/off switch extends a bar between the two vertical positions of the 12/16 switch (on meaning locked and off meaning changeable).

Here's a short video of how it moves when the advance is at the end of the roll:
https://i.imgur.com/0yRZ9Hz.mp4

This does then beg the question of how the "auto" advance works.... with no film loaded, the advance wheel turns freely without stopping anywhere. Am I supposed to just use the alignment of the frame counter numbers with the indicator arrow to advance?

Thanks so much to everyone offering suggestions!

 

[Dan Daniel]

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[brianssparetime]

I think that's right. When I turn the advance knob, I do see the spindle turn and the frame counter turns at a different, much slower speed.

It appears that on many Mamiya Six models though, there is a feature that stops the advance knob from turning further once you hit the next frame. After taking a photo, you then slide the arrow lever (where my 12/16 lever is) left to unlock the advance knob, which then turns freely until stopping at the next frame.

Mine doesn't stop anywhere though....

So I'm wondering if I just use the frame counter and indicator arrow to know when to stop winding on, or if there's some way to engage the auto-stop mechanism assuming I have that?

 

[Dan Daniel]

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[shawn]

you definitely have the auto stop mechanism, I have the same camera. The models that don't have it don't have the switch at all.

I just grabbed mine. You do not need paper backing in it for the auto stop to work.

The way you use it is to wind until the camera is at the 1. (The numbers should stop advancing when you hit one) but you can keep turning the knob and the film advance will still turn. Load film and advance until you get the one in the window. Cock shutter and take your shot. You then push the lever to the left to unlock advance and it will wind to 2 and then stop and lock advance. Take the shot and the push the lever to the left to unlock advance again. Now it will wind to 3 and stop. After the 12th or 16th shot it will free wind (and the counter will stop at 1) allowing you to empty and reload the camera.

If yours isn't doing that it isn't working correctly.

Shawn

 

[shawn]

Any chance that the big black arrow is pointing to what to do to move to the next frame- push the 1z6/12 knob to the left?

The big black arrow is part of the film holder plate and is just pointing out how to feed everything. Once you close the back you can't see it. The Mamiya Six focuses by moving the film forward and backwards, not the lens.

Shawn

 

[brianssparetime]

Thanks Shawn - that's exactly right. Just gave it a go with some film. Thank you for the help!

 

[Dan Daniel]

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