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Mamiya 7 - DigitalBack Adapter Plate Concept

pedro39photo

New member
Any one know if its technical possible to make a back plate for great film Mamiya 7 system work with digital backs?

And sorry my bad photoshoped concept image...
Pedro





 
It has been done with a Mamiya 6. I can't find the images online any more, it has some monstrous extension to the eyepiece to reach back over the back.

Even though the back is removable on the M7II, my guess is it could not focus at infinity because the sensor is some distance from the mounting plane, so even if the adapter could push the digital back right up against the film guides, your capture plane would still be offset some distance behind the film plane ... unless of course you wanted to sacrifice the body completely and make an irreversible modification.
 
In your mock up, apart from the obvious perspective, which is hard to get right ... the Zeiss eyepiece is looking back at you!! :)
 

trev2401

Member
The museum i used to intern at, used heavily modified Mamiya 7 backs (version 1) with Veio backs then. I remember my jaw hitting the floor when i first saw one mounted on the copy stand.... It was a custom made back done by mamiya/leaf back in 2008.
 

Ken_R

New member
I am sure it can be done. It is just a matter of getting the math right and machining the parts. Most likely the Mamiya 7 will need to be made for digital back use only. Since the lenses use a leaf shutter you do not need to worry about a focal plane shutter being in the way. Many more details will need to be addressed of course but I think it is possible. Is it all worth it? That is the question.
 

MaxKißler

New member
I suppose the real issue won't be the modification itself but changing the frame lines in the finder to match the crop and aspect ratio of the digital format. Apart from that, rangefinder accuracy might be a problem aswell. Just because it works with film, doesn't mean it does so with digital. Keep in mind, digital means you get absolutely zero tolerance. Things like focus shifts (when stopping down slightly changes the lens' focal length) that are hardly visible on film will show up. Even if the rangefinder mechanism is calibrated and spot on, focussing will be very difficult too I imagine and the slightest focussing errors will be visible.

These are just some things to consider but after all someone should really give it a try. ;)
 

Shashin

Well-known member
Tolerances are not a big issue and the Mamiya 6/7 lenses don't have any focus shift I ever noticed. No, the big issue is you are making a frankencamera that would be a monster to use. My all-time favorite camera was the Mamiya 6. It was small and light, fast and easy to use, and inconspicuous. Everything this modification will not be. I would go for an Alpa TC with a nice Rodenstock. By the time you sink all the money and time into this conversion, you can easily afford the Alpa. And it will be bigger than a TC. Either that, buy a Leica M9, ME, or M, if you want a rangefinder.

But it can be done. But you are making a digital only camera.
 

fotografz

Well-known member
There was a NPC Polaroid Film Back for Mamiya 6 and 7 series Cameras (now discontinued). I had one. You removed the film door on the camera and replaced it with the NPC Polaroid back. It had a 6X7 fiber optic lens in front of the Pola film carrier, and also accommodated a dark slide ... which all then worked like all the other Pola film backs.

It seems the fiber optic lens allowed the pola film to be further back than the roll film would have been. I think it may have had to be in direct contact with the Pola film pack which probably would not be optimal for a digital back sensor (Duh!). All I do know is that it focused to infinity.

If you could get one of those, it may show exactly where the digital sensor has to be ... or even perhaps could be the thing to modify for a digital back. (???).

I no longer have it, it's been gone many years, so I can't look at it to see if it helps or not.

NPC Polaroid Film Back for Mamiya 6 and 7 Series CamerasMF22 B&H

- Marc
 

pedro39photo

New member
" I would go for an Alpa TC with a nice Rodenstock. By the time you sink all the money and time into this conversion, you can easily afford the Alpa. And it will be bigger than a TC. Either that, buy a Leica M9, ME, or M, if you want a rangefinder.

But it can be done. But you are making a digital only camera.
Yes you made a good point, but mamiya 7 lens are great lens with a fraction of the costs of Rodenstock, if this conversion could be possible will be a low cost alternative to "ALPA" like systems.
I love to see this adapter come to market, but it had to made with great detail expertise because of the tolerances. and including a "shim" Kit like ALPA. hehehe
 

Shashin

Well-known member
The adapter would also have to engage the film transport system as the lens shutters are cocked when the film advances.
 

pedro39photo

New member
The adapter would also have to engage the film transport system as the lens shutters are cocked when the film advances.
I think that the shutter lens cocked with film lever rotating not with the help of the film, but i am not fully certain of this.
 
I can't tell you whether it can be done (i.e. if it works well), I can tell you that it has been done. They pop up on eBay from time to time for about $4,000 out of Hong Kong but I don't think anyone here has used one. If you search on here you should be able to find a link or pictures.

The Mamiya 7 is a supremely elegant camera, but I think you lose that elegance by sticking a huge digital back on it. It would seem like going with an Alpa or the new compact Arca would make more sense.
 

ondebanks

Member
Yes you made a good point, but mamiya 7 lens are great lens with a fraction of the costs of Rodenstock, if this conversion could be possible will be a low cost alternative to "ALPA" like systems.
I love to see this adapter come to market, but it had to made with great detail expertise because of the tolerances. and including a "shim" Kit like ALPA. hehehe

So your main motivation for this is not really to use the M7 camera with a digital back, but mainly to use the M7 lenses with a digital back?

If you are willing to forego their leaf shutters, you might be able to just mount the M7 lenses on a slim, non-reflex, focal-plane shutter MFD platform like the Hartblei or Alpa FPS. I'm making two assumptions here -
1) When off the camera, can the M7 lens shutters be in an open state? The lenses I've seen for sale seem to have their shutters closed...
2) Are the Harblei and FPS slim enough (or can the lens adaptor be recessed enough) to get the M7 lens close enough to the sensor for infinity focus?

I like this idea; it would be great if it worked.

Ray
 

alajuela

Active member
Hi

I think this is a nice arts and craft project but not logical.

Why keep thinking in the same confines?

Facts..

1. The Mamiya 7 is an elegant camera

2. Has great lenses.

3. Not so heavy

4. Satisfies that "Ranger Finder Lust"

5. Phase owns them.

6. The S2 and Pentax both have "captive sensors" this has not stopped either of them from being successful cameras with a very loyal user base.

7. Phase has an entire inventory of sensors and technical ability (I would assume more than one Mamiya engineer is still on thier payroll).

I think Phase should put all this together and bring out a ranger finder camera with a large as possible captive sensor (maintain the aesthetics) - does not need long exposure.

You would have the best mirror-less almost tech camera there is. No Mirror, nor FP shutter vibration.

They could even make a model, coat it in snakeskin and wipe the lunar off the map.

A real Lamborghini - Form follows function and so - functional and so - beautiful form. Like an F16.

Phil

ps- Still want a film option, a used Mamiya 7 body is really cheap on the second hand market
 

Shashin

Well-known member
I think that the shutter lens cocked with film lever rotating not with the help of the film, but i am not fully certain of this.
I am basing this on the Mamiya 6, but the film advance lever does not cock the shutter directly and the shutter will not fire without the film reach the first frame. I also know if I lose power, the film cannot be advanced without taking the lens off and manually cocking the shutter and so I think it is not a simple mechanical connection. Whether you can use the multiple exposure feature to get around this, I do not know.

I like Rays idea if you can find the connections to open and close the shutter. You might fashion a simple timer to control the exposure.

I liked my Mamiya 6 lenses and it would be nice to use them. I still have one Mamiya 6, my first. I just could not bring myself to sell it.
 
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