Any experience with Rollei prism adapted for Mamiya TLR?

[villagephotog]

I’m thinking about getting a prism finder for my Mamiya C220. The obvious choice is Mamiya’s own prism finder for the C-series TLRs, but I’ve seen mention in several places of Rollei prism finders that have been modified to fit on Mamiya TLRs. (Always the 90° prism in the pictures I've seen.)

Anybody have any experience with this, or know why folks made this modification — i.e. what advantages it has over the Mamiya prism, if any? Maybe it actually has disadvantages, I dunno?

 

[Neil Grant]

...the Mamiya prism is extremely heavy and putting it ontop of what is already a very tall camera impairs the balance. On a tripod this may pass unnoticed but hand-held is a different matter. At the very least I think you'd need to attach a side grip to the camera to make it manageable. For hand-held, eye-level photography, the lightweight 'Porrofinder' makes real sense with these big, tall C-series cameras - they just feel much steadier.

 

[Marco Gilardetti]

It doesn't seem to me that the Rollei prism is significantly lighter, smaller and/or cheaper than mamiya's original one, so I can't even see the point of adapting it to a different camera. Is there any?

The only "pro" of porrofinders is that - being made with mirrors - they are very light. Under all other sides, size including, they are really nothing to write home about. The image they deliver is small, far, dark, and they don't have a sight correction dial.

 

[Main_Cogg]

@villagephotog , I have 2 Porrofinders that I have no use for that can be yours for the price of postage. I know very little about them, they were in a box of gear that came my way a few years but there wasn't a camera to mount them on. Neither one of them is perfect but I'm pretty sure that with a little effort you could have a usable finder. Shoot me a PM if you're interested.

 

[Sirius Glass]

I had convinced my father to use the Porroflex. Once he had if on his C330, he never took it off. And yes he used a pistol grip of a side grip too.

 

[MattKing]

the Mamiya prism is extremely heavy and putting it ontop of what is already a very tall camera impairs the balance.

I used one for years doing wedding work, and never found this to be the case.
It always used it with a left hand trigger grip, and often had a Metz 60 CT flash attached to the grip as well.
Here is a camera with prism attached - albeit on a tripod:

In some markets there may be more Rolleiflex prism finders around. That may be why people have adapted them.

 

[grahamp]

There used to be a Kiev prism modification available from Germany. I don't think it is around any more, though I may be wrong.

You need to ascertain three things:
Does the prism you want to use cover the Mamiya screen?
Is it feasible to make a mounting adapter to mount the screen to the Mamiya lugs and clamp screw? And does the prism overlap enough to foul the strap?
Will the adapter place the base of the prism at a suitable distance from the screen?

Those three conditions interact - if the prism is mounted too high, coverage will be reduced, and the adapter governs the spacing.

Over the years I have learnt to adapt to direct vision, SLR, TLR, and view cameras, so I don't feel the need to a prism, but if a prism is what you need you only have a limited set of options.

 

[villagephotog]

Thanks for the input, everyone. I didn't really expect anyone to have experience with this particular tiny corner of the photo world, but thought I'd ask.

If anyone's curious, KEH must have had at least one at some point, and they still have pictures of it here: https://www.keh.com/shop/mamiya-twin-lens-rollei-prism-modified-to-fit-mamiya-twin-267281.html

It's got all the right Mamiya connections; looks like maybe the Rollei part was cemented onto a base taken from a Mamiya finder of some kind (maybe a broken WLF?). Hard to know.

And I asked because there's currently one for sale near me (might be the same one that KEH had ). I'm only mildly interested, but there's a whole lot of experience on this forum, so I thought I'd see if anyone knew anything about it.

 

[Neil Grant]

...i think the Rollei prism looks smaller than the Mamiya one. Maybe it was introduced before Mamiya got around to doing their own prism. They were also slow on doing Porrofinders - the first ones were from Nikon.

 

[Neil Grant]

C 330s with Porrofinder and side grip.

 

[Marco Gilardetti]

Around 35 years ago I made with scrap material an adapter that would allow the metered prism of the Pentacon Six to be mounted on top of a C330. The reason why I did it was that in those years things like the CdS Porrofinder were basically non-existent in Italy, and would cost a fortune anyway. Contrarywise, after the Berlin Wall came down, accessories for the Pentacon Six were easily available and relatively cheap. The P6 prism would cover the C330 groundglass only partially (around 70% perhaps) and of course recalibrating the meter was tricky, but I managed to have it working somehow.

I see many people did more or less the same thing with the Kiev 66 metered prism. Again, to some degree, this is reasonable. The lack of a real metered prism is the most evident missing part in the Mamiya C system, in my humble opinion. Something I still wonder about today, decades later.

What I really fail to understand is why one would do the same thing with a Rollei prism. It isn't metered, is it? And also pricewise, I figure it would cost more than Mamiya's original prism.

To make a long story short, as (many...) years went by and I begun to have a regular salary and bought large format cameras, I had in any case to resign to use a handheld meter. I still definitely think that handheld meters stink and are a major annoyance compared to a good built-in meter, but that's life. So I progressively quit the chase for a decent metered prism for the Mamiya C. However, recently I stumbled in a like-new CdS metered porrofinder, with case in box, and I frankly admit I felt I had to buy it just because I desired it so much when younger. I tested it but never really used it: its non-coupled spot meter is a pain to use in quick-shot scenarios - which ironically are exactly those in which you would like to have a convenient eye-level prism - and as said above I find it optically disappointing. It's perhaps my only real "collection" piece, with no real use.