Digital back for M film cameras

FrankS

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I know this very clever and talented inventor fellow who, among other things, builds robots/robotics for Hollywood movie films. His shop has C+C computerized milling machines, etc. I met up with him today because he had a few old cameras that he knew I'd like to have. Anyway, we chatted and I think that I may have got him interested in the concept of building an interchangeable digital back for the Leica film camera. Full frame would be nice of course, but we're thinking that on the scale at which he'd be working, he would cannibalize new Canon digital Rebel X camera bodies for the guts of this back. Unlike the digital camera built into the screwmount body idea, this digital back would be self contained and interchangeable with the normal film (pressure plate) back, and the M camera's shutter with speed controls, and the interchangeable lenses with their aperture controls would still function.

If this interests you, how much would you be willing to pay for such a back? (Keep in mind the cost of the digital donor camera.)

If this idea does not interest you, please just ignore this post and move on. I can judge the popularity of theis idea on the number of (positive) responses this post does (or does not) get. Thanks.
 
Unfortunately the crop factor does not appeal to me and hence I wouldn't be willing to pay too much for it - maybe $1000 USD tops.
 
http://www.dpreview.com/news/article_print.asp?date=0001&article=00010604siliconfilm

The EFS-1.

http://www.imaging-resource.com/NEWS/1000760900.html

I was really disappointed back in 2001.

As for a Digital Back for an M camera, Kodak made a Digital Back for the F3. That was 20 years ago. So, it is possible. The NRE would be a few $100K, probably in the $350K range. That would assume starting with a sensor development kit, a mechanical engineer, and a computer engineer that wanted to have a Mechanical Digital M.

We've discussed this before on RFF. With the introduction of the M9, and the availability of the used M8 in the $2000 range, it is hard to make an economic case for such a digital back.

I would easily pay $1500 for a 1.3x crop factor Digital back for my M3. Use a Monochrome Sensor, please.
 
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The price would need to be in the 1K under for smaller sensor and 2K under for a full frame sensor. I think that a sensor of at least the size of the new Pentax MF digital in the Mamiya 7 would be of greater interest for me since this creates a form factor/performance that would not be possible at any price. Of course, starting with a camera and pulling it apart for parts won't make this project cheap.
 
I, too, would love a monochrome digital back for my m4-p. I would guess that the 1500 usd that Brian suggests would sell like hot-cakes to hungry folks.
 
I remember that article from 2000 /2001. It was before my first DSLR. I'd love to see something like that for my M6 TTL.

Steve.
 
EFS-1 is the most clever thing I have ever heard of. You can switch to digital without giving up the film. And it can fit to any 35mm film camera virtually. It is unfortunate that it did not become real. for 1.3x crop the price should be <= 1000$
 
First of all, I would definitely like a Full Frame sensor for my M6. I if could get a digital sensor for an M, I would probably even upgrade to an MP. I would love a monochromatic sensor, but certainly would not pay as much than a color sensor. This is b/c, from what I undersatnd, RAWs are only shot in color, and I would want to shooot RAWs. What is the digital Rebel crop factor? 1.5?
I would pay for a:
1. 1.5X monochromatic: no more than $1k
2. 1.5X color/RAWs: up to $1500
3. Full Frame monochromatic: up to $2k
4. FF color/Raws: up to $3K.
It would be awesome to see something like this come into fruition!
 
If you can keep the crop factor on par with the M8 - ala 1.33X, then I'd be willing to pay what equates to an M8/M8.2 $2000-3000.

You'd better be sure the low light performance is up to par!
 
As Frankie discussed before, some crop factor must occur to position the sensor at the image plane. A full-frame sensor must have a border, and that would be problematic because of the film gate design. He previously wrote that a 1.06x crop factor could be realized. I'm not personally aware of a sensor with a 1.06x crop, but he has explored this issue more than I have.

A monochrome sensor is likely to be a limited run these days, and the price would not be any less than a color sensor. It depends on volume and if the sensor offers a monochrome option. The Kodak KAF6300 series was offered in color, monochrome, infrared monochrome, and color infrared.

Sensor companies are more open to discussion than a lot of people might believe. Kodak made the first Infrared DCS camera after talking with them 18 years ago about it. They had a laugh, telling me that they expended a lot of research making Silicon sensors look like film with regard to spectral response, and that I wanted them to undo all of that. Kodak continued offering IR cameras and Monochrome cameras through the DCS760.
 
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Sure. it's done right. I'm price insensitive really if I can use my M7s with no significant external differences -- ie. the depth of the body doesn't increase (much?)

1.33x at the minimum. Smaller is a deal killer for sure.
 
The combined unit will be larger than an M8. There has to be a housing for the sensor and it's electronics. An off-the-cuff guess would be about the size of a Winder and a databack. Frankie had the clever idea of using the film compartment for a battery. Efficient use of space. With a sensor and 14~16-bit A/D's, you need a good bit of isolation between the Analog and Digital side of things. A 16-bit and better A/D allows non-uniformity correction to get rid of light fall-off at the edges of the sensor.

Like we stated before, all this project needs is one really rich Leica user that JUST HAS TO HAVE a digital M3. But for the rest of us, a used M8 at $2K is a great 1.3x crop camera, and the M9 at $7K looks cheap when you price out full-frame sensor development kits. Check Digi-Key.
 
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I have just returned from our annual industry conference...

A new 11,200 x 11,712, 7.2u pixel size monolithic panchromatic sensor custom-built by Dalsa was successfully used by Zeiss in the form of a new 130 mega pixel RMK-DX aerial camera.

Dalsa will make custom sensors, even super size sensors if an order is large enough.

Brain Sweeney had been diligent reading the sneak posting I made since I left to avoid confronting the Thought Police.

I personally believe a hundred thousand plus abandoned film M owners would be happy to send in a camera to authorized CLA person for a retrofit...if I bother to offer the package when ready.
 
I have just returned from our annual industry conference...

A new 11,200 x 11,712, 7.2u pixel size monolithic panchromatic sensor custom-built by Dalsa was successfully used by Zeiss in the form of a new 130 mega pixel RMK-DX aerial camera.

Dalsa will make custom sensors, even super size sensors if an order is large enough.

Brain Sweeney had been diligent reading the sneak posting I made since I left to avoid confronting the Thought Police.

I personally believe a hundred thousand plus abandoned film M owners would be happy to send in a camera to authorized CLA person for a retrofit...if I bother to offer the package when ready.

I'm reliably informed that Winston Churchill kept a large engraved sign on his desk thru WW2.....................ACTION THIS DAY.
It worked for him.
 
I've alpha tested new computer boards before... like Today, for example. HEX file was corrupt, had to re-assemble and reflash the processor!

and alpha tested new Digital Imagers before. 30 years ago.
 
We have a new forum especially for discussing such projects...

I know. Perhaps we can move that old thread to your new forum?

You might have also noticed I had posted an entry about "shim stock" and another about rubber eyepiece ring. Sure beats damaging expensive eyeglass lenses...at $12.95/100 pieces.
 
This was the 1.06 crop factor post Brian was talking about:

"After much thought, it occurred to me that if a FF CCD encased even with a 1mm thick rim [22 x 34mm net CCD size] would work fine (~95% coverage). The M framelines are only ~85% accurate anyway.

One CCD vendor contacted would/could package their chip that way upon a "large enough" order.

Such an encased CCD could be mounted in a way to fit through the shutter opening [net available depth 2mm, enough even for filter layers and cover glass], with the image plane aligned with the film guide rail top surface. The rest of the pins and frame materials are behind that plane and would not matter. No surgery needed.

A crop factor equivalent of 1.06 could not hurt much. I don't care if a 50mm lens is now really 53mm or a 35mm is really a 37mm. Most M-users could never compose to the true FF anyway.

The 45 x 90 x 7mm space now occupied by the back door could indeed be used to fit most of the simple Frame Grabber, Buffer and Write-to-SD electronics. If need be, place some of the components in a multi-layer board in the space now occupied by the removable take-up spool. Some more work needs to be done.

Many lithium-ion 1600 mAH battery fitting in the film cartridge space are available.

It also occurred to me that if a 24 M-pixel 16-bit B/W raw-only conversion is made, a 2Gb SD card would only hold about 40 shots. The existing camera frame counter is therefore perfectly usable...especially the M2. If I must use HC/SD, I can keep track mentally...or use only 2Gb SD, <$10 each. So change SD as frequently as you would using film.

Upon discussing with a few old-timer friends, we all agreed that if someone handed you an M2/3/4 camera pre-loaded with Tri-X, you would simply shoot away...using a hand-held meter or not. You could not and would not care if WB is daylight or otherwise. And, knowing there are a few stops of underexposure latitude helps a lot.

Considering colour: the minimal "new" control needed is selecting WB between 5600- and 3200-degrees k with Auto in between. The M2/3 and MP rewind knob is perfect for conversion into functioning as such a 3-position toggle switch. Rotate the engraved arrow head to a new detent either at the 1- 3- or 5 o'clock positions. Fine colour tuning can be done in post-processing.

If full-Auto WB can be made reliable, no such toggle switch is even needed.

Use an i-Touch or i-Phone for chimping after-the-fact. Assessory devices are now available.

The real issue for me is how to deal with M owners with bad shutter, RF or cannot shoot with sunny-16. No doubt they would think something is wrong with the DIY package before checking their own equipment...first.

Perhaps a mandatory CLA plus d-M package installation service can be organized...just like in my stereo plotter retrofit old days."
 
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