The problem started when Folmer & Schwing changed their name to Graflex in 1945, which happened to be their most distinctive and popular line of cameras prior to that. So there was a Graflex company and a Graflex camera. There other popular line of camera was the Speed Graphic. The Graflex was an SLR, so there was no real need for a ground glass back on the camera. Film holders, film pack adapter backs, cut film magazines and rollfilm backs slipped into a channel on the bottom, and a sliding bar locked them in place from the top. On double sided film holders this became a groove on the edge of the holder, although it is really one rail for each side of the holder. The face of the film holder (or other device) had a groove on the face that positioned it correctly horizontally. The film holders and rollfilm backs are referred to as "Graflex" holders, and "Graflex" rollfilm backs, named after the camera they fit.
The back of a Graflex SLR
Because the Speed Graphic was not an SLR, it was nice to have the ability to focus on a ground glass. Many users never regularly used this feature, they focused with the rangefinder and composed with the viewfinder. This was essentially a fast moving press camera. The back was fitted with a ground glass focusing panel which did not have to be removed to load film. It was mounted on two pieces of spring steel which would allow it to move out away from the focal plane, the springs holding it tight against the film holder. The film would now occupy the same plane as the ground glass did before the holder was inserted.
The Graphic back
The Graphic back with a film holder in place
In a perfect world Graflex would have designed both backs to use the same film holders, but apparently this is not a perfect world. The holders for the Speed Graphic lack the groove running down the edges, and are longer and a bit narrower than there Graflex counterparts. The locking groove on the front is replaced by a ridge, which of course, is in a different location. The back for the Speed Graphic is sometimes referred to as a "spring back" or a "Graphic" back.
A Graphic holder on top, and a Graflex on the bottom.
That would have been bad enough, but they made an improvement on the Graphic back. They redesigned it with a removable focusing panel. You push down on the two chrome rails (one immediately above and below the panel) and it can be removed, and a rollfilm back mounted in is place. The film plane maintained a constant location, so the camera could be focused by rangefinder or ground glass regardless of which film holding device was used. The new back was named "Graflok", but it was designed to accept the older Graphic film holders. So for some unfathomable reason (at least to me) Graflex further muddied the waters by marking their rollfilm backs as Graphic backs in spite of the fact that they will not fit cameras with a Graphic back.
The Graflok back
A Graflok with a film holder inserted
A Graflok with the focusing panel removed.
Graflex made their rollfilm backs for 2-1/4 x 3-1/4, 3-1/4 x 4-1/4 and 4x5 format cameras. For simplicities sake I am going to refer to the first two as 2x3 and 3x4 from here on out. I'm not a touch typist. The 2x3 size Graphic back is by far the most commonly found. The 4x5 isn't too hard to come by, the 3x4 is the least common. The 2x3 Graflex is probably about as tough to find as the 3x4 Graphic, the 4x5 Graflex is a bit tougher and the 3x4 the hardest of all to find. That doesn't necessarily affect the price that much as the demand is highest for the 2x3 Graphic. The others command a small premium.
Rollfilm backs for the 4x5, 3x4 and 2x3 size cameras
The Graflex holder, left, and the Graphic holder on the right
The rollfilm holders for each size and model of camera were available in three formats; 6x6cm, 6x7cm and 6x9cm. Early holders were either marked 22 or 23, the 22 being 6x6 and the 23 being 6x9. With the introduction of the 6x7 format the designation changed to RH12 (6x6), RH10 (6x7) and RH8 (6x9). The number described the number of exposures obtained on a roll of 120 film. Other holders were designed for 220 using a different pressure plate. I am not sure which formats were available for 220, one would think they all were, but I am not certain. I know we've had RH20 holders before, so I know that at least they were offered. Also a back was made for 70mm rollfilm in cassettes, only for the 4x5 cameras and the Graflex XL cameras (by means of an adapter). It was the RH50.
The later holders used a lever for advance instead of the earlier knob, and had rollers at either end of the film gate to help hold the film flat during exposure. Some of the latest holders are marked Singer (yes, the sewing machine company) when Graflex was owned by them.
The lever and knob wind holder, the lever being a late one marked Singer
The later style holder on the left with the tension rollers
One must be careful when buying a rollfilm holder, making sure the format of the frame matches the exposure counter on the insert. Any format insert will fit any format frame. A mismatch will create either overlapping frames or excessive space and a waste of film.
Another film holding device is the Grafmatic back, which holds six sheets of film in individual septum that you preload in the darkroom. They opened like a drawer to move the exposed sheet to the bottom of the stack. A counter kept you from cycling around to sheets that had already been exposed.
The Grafmatic closed
Open to advance to the next sheet
Open to load, showing septums
An earlier version of the Grafmatic back was the Cut Film Magazine. It held 12 septums, and they were changed by pulling them out mechanically into a leather compartment. Because of the leather bag hanging off one end they are often referred to as Bag Mags. They only fit the Graflex SLR cameras, and came in sizes ranging from 2x3 to 5x7.
The Bag Mag closed
Open to show the septums