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No. While it may be "technically" possible, the images will be out of focus. The pressure plate is made to hold down 220 film (no backing paper)
The thicknesses between the two types of film are different. This is the same reason one cannot(again, technically one can)use 220 film in a 120 (A12)back. Cameras that allow for both types of film within the same holder, have a rotating pressure plate for the different film types.
"While it may be "technically" possible, the images will be out of focus."
I don't believe that is correct information. From my understanding, there is no difference in the part number for the two pressure plates. They both press the film up against the dimensionally same film gate (film plane), 120 or 220. The film gate (and film plane) for both the 120 and 220 backs are at the same same position, as they should be.
The differences in the two backs are in the gears, which account for frame spacing and for frame counting. You can convert an A12 back to an A24 in fact:
"This is the same reason one cannot(again, technically one can)use 220 film in a 120 (A12)back."
Again, the pressure plates etc. are exactly the same for the A12 and A24, so there is no reason, except frame spacing (which is different between the 12 and 24 backs), and number of images/end of roll, that you should not be able to use 220 film in an A12 back.
"Cameras that allow for both types of film within the same holder, have a rotating pressure plate for the different film types."
Not entirely true. The Rolle 2.8F 12/24 does not change the pressure plate, the only difference is in the frame counter.
There is a difference, as you state, in the thickness, but whether you have to change the pressure plate setting or not is really design dependant, and as such, some cameras need it, and some don't.
Austin, I may have "jumped the gun" in my response by generalising. I am not a Hassie user anymore. My experience comes from ownership (past) of a Pentax 67 and my current Contax 645.
If you have the pressure plate wrongly oriented, your images will be out of focus. Spacing is another issue.
The images will only be out of focus if the film is positioned at the wrong spot. For the Contax 645, there is a 220 vaccuum insert, which can not be used with 120, and this difference would necessitate different "pressure" plate positions, as the 120 would be front justified, and the 220 would be rear justified. Not sure about the Pentax 67.
I checked my Fuji GS645, as well as my Plaubel Making 670, and both have a different pressure plate setting for 120 vs 220.
The most important reason why 120 film cannot be used in vacuum backs is, of course, not to do with plate positions, but the simple fact that the vacuum back would hold the paper very flat, but not the film itself.
> Why is it excactly that there need to be paper on 120 rol film - would it not have been just as easy to do a cassette or other item to avoid the paper ind if so would the advantage of vacum not be bigger on 120 film then on 35 film ? I know in these digital times we are not up for changes on films but just wondering.
The paper on 120 rolls of film is there to protect the film from light. There is no cannister or anything else, just a rolled up film, with paper.
Yes, a cassette would be another solution to the problem.
But 120 film is very old. People didn't care in the same way about convenience then as they do today. After all, it (120 film, no cassette) works quite well, doesn't it?
Since the film needs to be protected while being loaded and unloaded, 220 film only has paper on both ends of the film, wrapping both beginning and ending of the film light-tight.
No paper, means smaller diameter of the roll. Which in turn means there can be more film on a roll and not be wider, i.e. still physically fit in a magazine designed to take 120 film.
So 220 film has twice thelength of 120 film, which, of course, means twice the number of frames too.
Of the two, only 220 film works with vacuum backs. That's why the Contax 645 vacuum back takes 220 film only.
And yes, the larger the film, the more it will benefit from some means to keep it flat in the film gate.
There are, for instance, LF film holders available that have a "sticky tape" like adhesive covering. Large format aerial cameras use vacuum plates too.
However, we have managed quite well for many years with 120 film and without vacuum backs, haven't we? So it must not be a problem desperately in need of a solution (like vacuum backs), right?
> I was only wondering - I am quit happy with my 120 film cameras - did once have an aviation camera that took roll fil at about 30 cm wide. It had a vacum back and would have made 30 x 30 xm shots. When I found out the price of getting the films from trhe US I sold the camera ( it did have a bausch and lomb optic ( don know about the spelling but it was the same company that made RayBan sunglasses
Ruben, the reason for the backing paper is that 120 and the old 620 films were/are used in cameras that require the user to wind on the film until the frame number appears on a red filtered window on the camera back. Such cameras did not automatically advance films with cogs and gears the proper distance. In addition such cameras were designed for 12(6x6),16(6x4.5) or 8(6x9)images. Consequently, the paper backing had all sorts of number sequences printed on it to accomodate the variety of cameras such film could be used in.
You will be fine, I have done it many times (in a pinch) your spacing may get a little off, but it'll save you if for some reason you only have a 24 back and a roll of 120. I have also gone the other way, loaded 220 into a 12 back.. I only shoot 12 shots (spacing will be a little tight) but it is possible. By the way, I am new to the board, thanks for all the great info. I was looking to see if anyone else had the same problems as me with the 203 (which I will post on another thread)... I also see that an excellent photographer/colleague of mine, Pete Calouri is on this board, it is a pleasure to be in such great company! -Ryan Kercher
Black Forest Photography
Black Forest, Colorado