Stupid question time: Plate vs film holder.

[Jmarmck]

I found a camera that says it comes with plate holders. The photos of the "plate holders" show them with natural wood frames. It this the same thing as a film holder like a riteway or fidelity?

[Vaughn]

Not the same. Plate holders are designed to hold glass plates (obviously), but since glass is thicker than film, it one uses film in a glass plate holder, the emulsion will be in a slightly different plane than the emulsion on glass would be (farther away from the lens)-- meaning you art not focused where you think you are. Sheaths are available for using film in plate holders to correct for this.

Also older cameras made for glass plates were not as standardized as modern cameras -- holders from one might not fit another.

[Mark Sampson]

Plate holders are, you guessed it, made for glass plates. Some makers made 'sheaths' that allowed you to use sheet film in those holders, although I've never seen any; I'd assume those to be rare items at this point. Some sellers don't know the terminology for sheet film/plates, and may be calling sheet-film holders plate holders, or vice-versa. If you post a picture, the experts here will be able to give you the correct ID.

[Bob Salomon]

Linhof made Glass Plate/Sheet Film Holders that were about twice as thick as their regular Sheet Film Holders and had a spring loaded platform inside the Glass Plate/Sheet Film Holder that compensated for the difference in thickness between a glass plate and a sheet of film. Also, glass plates were easily scratched so the Glass Plate/Sheet Film Holders that Linhof made had a side mounted ejector lever that partially ejected the glass plate to eliminte scratching. It also worked when sheet film was loaded into the holder. This system eliminated the use of inserts or sheaths to switch from film to plates.

As an aside, the HP CombiPlan 45 and 57 developing tanks could process either glass plates or sheet film. If you assembled the film carrier with the curved grooves both facing in it was set up for sheet film. If you assembled it with the straight sides facing in it was set up for glass plates. If you assembled it with one curved side facing in and one straight side facing in it could not properly load either glass plates or sheet film. If you used sheet film with the staight sides facing in the film could fall out. If you used glass plates with the curved sides facing in the plates would not load into the slots.

Both the Linhof Glass Plate/Sheet Film Holders and the Linhof Sheet Film Holders were available with or without numbered frisk its that would number each glass plate or sheet film from 1 to 12 with a small number on the bottom, center of the edge of the film or plate. So it was very easy to determine which side of which holder shot which film or plate.

[Jmarmck]

Thanks guys. This is what I figured. Now the next obvious stupid question then is whether or not I can use a film holder in the camera. The camera is an older Korona III 5x7. The plate holders look fairly new.

[Chuck Pere]

Are 5x7 film sheaths standardized so they fit any older plate holder in place of the glass plate? I've seen Kodaks for sale on Ebay. The Kodak type is what I use for my 9x12cm holders.

[Petzval Paul]

I have sheaths that work with my whole plate film holders. I actually prefer loading them to using a regular film holder. The sheaths pop out easily and are a breeze to load. I am sure that could be found with a little patience.

[Bill_1856]

My 9x12 ICO/ZEISS Ideal has a little lever that moves the focusing distance scale forward/backward a tiny amount to compensate for the difference between plane of focus for plates and film. I've never seen that on another camera.

[Bob Salomon]

My 9x12 ICO/ZEISS Ideal has a little lever that moves the focusing distance scale forward/backward a tiny amount to compensate for the difference between plane of focus for plates and film. I've never seen that on another camera.

But other cameras had compensation for changes in film plane or film thickness in other ways:

Hasselblad added a glass plate to their Polaroid backs to compensate optically for the difference in film plane position between roll and Polaroid film.
Many 120/220 cameras had an adjustable pressure plate to compensate for the difference in thickness between 120 and 220 film.
Linhof used the previously mentioned spring plate to compensate for the difference in thickness between glass plate and sheet film.

[Arne Croell]

121200Here is an image of an old Voigtländer 9x12cm plate holder (top) with film holder sheath (bottom). Note the red velvet - it might only be lighttight for orthochromatic emulsions. Also be aware that the older style plate holders (not the Linhof ones Bob mentioned) were only partially standardized, the main difference was the thickness and the construction of the edges. There were at least 4-5 different versions around for each format.
The introduction of adapter sheaths for using film in plate holders is actually the reason that sheet film sizes are slightly smaller than the nominal size- the nominal size like 4x5" always referred to the plate size, and the adapter reduced that a bit.

[Jmarmck]

I decided to pass on the Korona III. I think the money would be better spend elsewhere.
Thanks for help.

[goamules]

I use sheaths in some plate holders. But if I didn't have them, I'm sure I'd just get some glass or Plexiglas the right thickness, and find a way to temporarily "stick" the film onto it while in the holder. The film would then be at the right level, and you'd be fine. Maybe a tiny piece of folded "yellow sticky" in places would work.