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manolo

New Visoflex for M9

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"and for the weather-sealing: It is just another M mount; if they solved the first, they just do it on the second."

 

Well, no - all the places where your blue lines meet red or green or dotted-blue lines will also need sealing. They all represent seams between body parts.

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Reality check:

 

The total thickness of anything that will mount R lenses and allow infinity focus can be no more than 47mm - image surface to lens mount surface.

 

The M image-surface to lens-mount distance is 27-point-something mm

 

That leaves about 19-20mm for any adapter to fit R lenses to an M body. That is not enough room for even a pellicle (non-moving) mirror, which to cover a 24 x 36mm image area must be 33mm in smallest dimension (24mm x sqrt-2 because it is sloped 45 degrees)

 

It is barely enough room for a pellicle mirror on the cropped M8, which needs 18mm of thickness. It is not enough for a swinging SLR-type mirror on the M8 (requires 25mm)

 

IF a Leica M ever has live-view, it would be possible to use a regular R-to-M adapter, and add a slide-on EVF (like the Panny GF-1). The M9 won't have live view. End of story.

24/sqrt(2) indeed : = 17mm about... a (theorical) 2-parts mirror, one swinging up, the other swinging down (there has been a MF SLR made like this... first Bronica, maybe) could represent a razor-limit solution...but one has to reason upon the bayonet blades... I give up to F... (another member) the detailed solution...

)

Speaking seriously, they simply won't do such a thing.

Edited by luigi bertolotti

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Don't get me wrong, I would love a solution like this, but imo it is either impossible or prohibitively expensive.

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Don't get me wrong, I would love a solution like this, but imo it is either impossible or prohibitively expensive.

 

Jaap... I have to totally agree. I have a Visoflex III and have both an R and K adapters. The basic problems is the focal point. the further from the sensor, the more it becomes a close focus. Even a fraction of an inch changes it tremendously. The only way it could work is if Leica put a lens in the Viso to correct this, but the cost (image quality) would be excessive.

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Adan, your calculations are correct, IF the housing is filled with air. The calculations are NOT correct if the housing is filled with high index of refraction glass. eq look at fish in an aquarium. The water changes all the relationships because of its index of refraction.

 

This thread is about a reflex housing for the M9 that would use R lenses focusing to infinity; it is not about all the other issues people would like to see addressed.

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"and for the weather-sealing: It is just another M mount; if they solved the first, they just do it on the second."

 

Well, no - all the places where your blue lines meet red or green or dotted-blue lines will also need sealing. They all represent seams between body parts.

 

not quite, but with more work & expertise it seems easy enough.

Edited by manolo

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I thought this one out a couple of years ago. It seemed like a neat idea, but in the end it looked easier and cheaper to develop an M-body and an R-body that used the same sensor, shutter and electronics.

 

Yes but I wouldn't be able to buy both cameras.

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if the housing is filled with high index of refraction glass. eq look at fish in an aquarium. The water changes all the relationships because of its index of refraction.

 

This thread is about a reflex housing for the M9 that would use R lenses focusing to infinity; it is not about all the other issues people would like to see addressed.

 

that is all we need.

Edited by manolo

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Adan, your calculations are correct, IF the housing is filled with air. The calculations are NOT correct if the housing is filled with high index of refraction glass. eq look at fish in an aquarium. The water changes all the relationships because of its index of refraction.

 

This thread is about a reflex housing for the M9 that would use R lenses focusing to infinity; it is not about all the other issues people would like to see addressed.

 

so all we need is an R adapter with a high index of refraction mirror (for the M9,m8,m7...)

Edited by manolo

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Manolo, it would not be a mirror. It would be a beam splitter. This is two pieces of glass block with 45 degree faces and joined together. The interface joint sends part of the light to the finder the other part goes to focal plane. There are no moving parts. The meter works as it normally would because it is not blocked by a mirror. There is no mirror black out. The finder imager is 2/3 stop darker. The image at the focal plane is 1/3 stop less than the set aperture.

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If the mythical mechano-optical beast was built, no one would buy it as a Canon 5D would be cheaper. An M9 with live view would even be easier to manufacture. I still play with a Visoflex and have used it for a wedding on a tripod for selected shots by pre-focussing and lock up the mirror then engage with subjects and have perfect shutter response available thats how some pro's use medium format. Personally I can live with using Visoflex or R optics on a non Leica SLR. If you really need to be all Leica branded how about an R to M adaptor and a Leica laser rangefinder?

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Manolo, it would not be a mirror. It would be a beam splitter. This is two pieces of glass block with 45 degree faces and joined together. The interface joint sends part of the light to the finder the other part goes to focal plane. There are no moving parts. The meter works as it normally would because it is not blocked by a mirror. There is no mirror black out. The finder imager is 2/3 stop darker. The image at the focal plane is 1/3 stop less than the set aperture.

 

everything sounded grate until:

 

"The finder imager is 2/3 stop darker. The image at the focal plane is 1/3 stop less than the set aperture.":(

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You can build a mirror that is not at 45 degrees by using a fresnel design. the Polaroid SX70 used this technology and got round a few space problems.

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If the mythical mechano-optical beast was built, no one would buy it as a Canon 5D would be cheaper.

 

The M camera and lenses are better for a lot of things (and smaller etc...) I have both M & R lenses and one camera would work for me.

 

If you really need to be all Leica branded how about an R to M adaptor and a Leica laser rangefinder?

 

If there is no R adaper for the M I will buy a canon (but I don't like the cosmos sensor and aa filter).

 

Could you look through the lens with that laser finder?

Edited by manolo

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The M camera and lenses are better for a lot of things (and smaller etc...) I have both M & R lenses and one camera would work for me.

 

 

 

If there is no R adaper for the M I will buy a canon (but I don't like the cosmos sensor and aa filter).

 

Could you look through the lens with that laser finder?

 

I am sure Leica have made hot shoe viewfinders for most focal lengths.

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I already said this, but it is impossible.

 

A far more easy and economic solution would be a M camera with a detachable electronic viewfinder (similar to that of the Panasonic GF1, but much better; or the EVF of the RED prototype) and a R-to-M adapter, but the sensor has to support live view.

 

But it is possible to make R-M adopter with rangefinder coupling mechanism. But yes viso soloution is better than this. Is it really physically impossible? If possible, Then I will not sell my R lenses. Otherwise my Rs-have to go.

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Yes but I wouldn't be able to buy both cameras.

 

One "open" body and the two adapters would probably cost more than the M and R bodies together. You'd be saving money by only having one set of electronic components (comparatively cheap) and shutter (which I hope is mass-produced), but each adapter (rangefinder and reflex) would have its full complement of (expensive ) optical components and precision engineering and - being Leica - hand assembly and testing. And there'd be another chunk of precision engineering and testing for the joint between body and adapter.

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so all we need is an R adapter with a high index of refraction mirror (for the M9,m8,m7...)

 

 

 

Reality check:

 

Have you allowed for way R lenses protrude behind their mounting flange (6 to 8 mm) and the required thickness of the M flange and the body of the adapter (>2mm in order to cope with heavy 400-1000mm lenses? In practice the space available for the mirror or prism would be only about 13mm.

 

Where do you put the 24x36mm focusing screen, an essential component of a SLR viewfinder?

 

If the adapter is full of high-refractive-index glass, where do you put the secondary mirror for the autofocus system?

 

How do you carry the electrical and/or mechanical signals for aperture and AF through the M mount?

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Show us your patent. It would make for some pretty fancy mechanics for the mirror movement.

 

Why would it need to be a mirror? electronics would not need a mirror.

 

Kevin.

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