Digital Conversion

[johnd]

Advertisement (gone after registration)

I was thinking about how"film" cameras are falling into disuse and have got cheap now that the bottom has dropped out of the market, including many highly-prized ones.

 

It struck me that it might be possible to fit the battery, electronics and light-sensitive screen inside such cameras, using the space where the two reels used to go.

 

This would give a new lease of life the old equipment, and need not even be destructive.

 

Does anyone know if this has been attempted?

 

Or maybe it is already available and I didn't know?

[el.nino]

Read the whole story here (starting in the middle with "What about Silicon Film"):

Leica FAQ — Full-frame digital M

 

And besides that:

No sensor/camera manufacturer would wan't to do this as it would mean a cut in digital camera sales.

Manufacturers nowadays do "good" in selling you a whole new camera every few years.

[adan]

The key problem with converting film cameras to digital:

 

The sensitive surface of film is the very front surface (no depth). Therefore film cameras are designed for focusing on the front surface of the imaging material - the positioning of the lens mount, SLR mirror/screen, shutter mechanism all assume that the place where the image should be focused is pressed flush against the back of the shutter opening.

 

Digital sensors have to have, at a minimum, a layer of protective glass in front of the image plane (the sensitive silicon). And in reality even more layers: infrared filter (remember the M8?), microlenses, anti-alias filter (if used). The place where the image should be focused is usually at least 1mm behind the front surface (even in the M9, the cover glass is 0.7 mm thick).

 

So simply slapping a sensor up against the film rails of a film camera will mean all the pictures will be out of focus, usless there are major modifications to the place where the film used to sit - basically, moving the whole shutter/film-rail complex forward a mm.

 

Essentially, using a hacksaw to cut out everything between the film chambers, cutting a mm or so off the front of that section, and reinstalling the remainder, now a mm or so closer to the lens.

 

So much for non-destructive....

 

The alternative is using a cropped sensor that can fit INTO the shutter opening, so that the protective glass layer is practically touching the curtains/blades, and the silicon is where film would have been. (Leica DMR does this, as did Kodak's early conversions of Nikon F3s, 8008s, and F5s - http://www.mir.com.my/rb/photography/companies/Kodak/index.htm).

 

Of course, a cropped sensor would change the view for lenses, so in a rangefinder, the frameline mask would have to be replaced with a new one with more tightly-cropped lines (a la M8).

 

Cameras designed around a digital sensor simply build the shutter closer to the lens in the first place (which is why a Zeiss Hologon 15mm (that just fit into an M4 or M6) can't be used on the M8/M9 - the lens-mount-to-shutter-distance is shorter and there is no longer room for that deep rear element).

 

Medium-format cameras with removable backs have the extra mm or so in front of the film already built-in (the thickness used to house a dark slide to cover the film when the back is removed from the camera) so it was relatively easy to use that depth for the extra thickness of a sensor's glass cover.

 

But MF cameras without removable backs (Pentax 6x7 SLR, Mamiya 6/7 or Fuji rangefinders) would required the major-surgery option, or the cropped-sensor-squeezed-into-the-film-gate option.

 

Minor considerations:

 

- there has to be a way to signal the sensor electronics that an exposure is about to start. "X" flash sync won't work, because it triggers when the first shutter curtain is ALREADY open. The "M" flashbulb sync on older cameras (designed pre-1970) would work. The Leica R8/R9 already had contacts installed in the camera to link to the DMR once it arrived.

 

Hasselblad uses the feeler pin on the back of their bodies, connected to the shutter button to prevent it moving if the dark slide is in place, to press a microswitch in their CFV backs and arm the sensor as the shutter button is pressed. Ingenious!

 

- using the "gut and resinstall" method, there would have to be minor tweaks to the connections between the shutter button/dial and the shutter, since the shutter clockwork is now a mm out of position.

 

The bottom line is - the bottom line. I'm sure I could convert anyone's "highly-prized" Leica M3 or Nikon F3 to digital for $20,000. Even to full-frame. It would not be non-destructive, and would probably require some changes in external size, even using the film-chamber space. Extra thickness on the back of 3-5mm, and something like the current Leica-Motor-M on the bottom.

 

"We have the technology!" But was a "$6-million-dollar Man" really worth it?

___________________

 

"No sensor/camera manufacturer would wan't to do this as it would mean a cut in digital camera sales."

 

Dalsa or Kodak (maybe even Sony and Panasonic) would LOVE to sell you sensors (with a minimum order) - it makes no difference to them if their sensors go into new cameras, or into camera conversions, so long as they get the cash. Kodak happily sold sensors to allow the conversion of R9s to digital. Kodak (or Dalsa or somebody) happily sell sensors for converting old V-series Hassleblads to digital via the CFV backs.

[St.Valentine]

Now that´s funny, this was exactly what I´ve been thinking for a while. How unfortunate that the industry is more interested in selling new cameras. I am sure they would have found a way around the technical problems involved.

[adan]

How unfortunate that the industry is more interested in selling new cameras. I am sure they would have found a way around the technical problems involved.

 

The industry is interested in making profits.

 

If there is a profit in converting film cameras to digital, they do it - see link in my previous post to the first Kodak DCS-100. Which cost $35,000 (talk about profit!). I know - I was in the meeting when they and Leaf and the Associated Press came and previewed it for the local news organizations in 1991.

 

Leica hoped to make a profit of the DMR - if they did not, it was due to other factors (like Imacon cancelling their cooperation before economies of scale had kicked in).

 

Hassy sells CFV backs today (3rd generation, now) - at a profit (one presumes).

 

Go to Nikon with an F3, or even an old F - and a blank check - and I'm sure they'd come up with a solution for you. Leave room for 5 figures, though.

 

Get 10,000,000 people to go in with you, and Nikon's eyes will light up like cash registers.

 

What Nikon (and most other camera makers) no doubt did was look at the figures and realize that about 99.99999999999% of the people who wanted digital cameras wanted coherent, well-engineered digital cameras designed as such. Only 0.00000000001% wanted (and would pay for) converting the dear old "highly-prized" film camera.

 

Digital conversions don't mean an end to new sales - as I mentioned, Hassy is on version 3 of the CFV back, so people need (or want) to "trade up" for newer conversions just as much as for new cameras.

 

It's pretty simple - show the industry that converting old cameras is more (or as) profitable than selling new ones, and they will change their "interest" really fast. But the key thought is "profitable" - not "selling new cameras."