Mamiya Press Models - Some Explained

Early Mamiya Press models:
Standard with bellows back and Standard 23 without bellows, small cavity, twist in bayonet lens mount with notch latch, and simple split image rangefinder/viewfinder with sliding/attaching mask arrangements for different lenses, limited parallax correction. Large majority of these models came with Mamiya back, a few with Graflex Graflok back. Changing backs possible on the Standard 23 by removing 4 screws. More difficult on the Standard because the bellows is glued to the back. The bellows back allows some close-up work and it allows the user to point the camera up and keep the film plane perpendicular to the ground and parallel to vertical subjects to avoid converging vertical lines and subjects. Limit, I believe, is about 10 degrees. This usually requires use of the ground glass back. I avoid the bellows camera to avoid the possible associated light leaks.

Super 23 Model:
Came later and had the Standard bellows back, small cavity, newly designed front, sophisticated rangefinder/viewfinder with changeable bright frames for 100mm, 150mm & 250mm lens, auto parallax correction, with lock ring style lens mount, no notch latch. Majority of Super 23 models came with Mamiya back, a few with Graflex Graflok back. Changing backs not practical unless bellows is re-glued to back. (If the back can be removed without tools it is called an adapter. Hence, the Universal (below) has an adapter, previous models do not.)

Universal, last model:
Same front, viewfinder/rangefinder and lens mount as the Super 23, much larger cavity to accommodate the Polaroid 3 1/2" x 4 1/2" format (picture size actually a bit smaller), easily removable and interchangeable back adapter system similar to the Graflex XL system. Back system originally comprised the "M" adapter for Mamiya accessories, horizontal format, "P" adapter for Mamiya accessories, vertical format, "G" adapter for Graflex accessories and Polaroid back, horizontal format. Other limited production after-market items became available also.

A few attempts were made at using 4x5 back accessories on the Universal and Graflex XL in conjunction with lenses to cover 4x5 and mounts and a spacing arrangement for the 4x5 back adapter. Without this mechanical arrangement and the 4x5 accessories spaced back about an inch, 4x5 coverage was not possible.

Today, it would be nice if the Universal would cover the 6x12 format - Can't happen, body just not big enough and only two of the entire line-up of Mamiya press lenses will just barely cover 6x12. They are the 75mm f5.6 and the 127mm f5.6, both of which were designed and marketed with the later black Universals for Polaroid use. These two lenses are the latest and best designs for the Mamiya press system. The 75mm appears to be a copy of the Schneider Angulon. It covers 6x12 but has severe corner light fall off when used with the 4x5 format.

About the true 6x9 roll film backs:
The 6x9 designation actually refers to the opening in the back end of the camera body that the back matches and I believe the Industry just referred to the backs in a similar manner. The Horseman back is 3 1/4" or 8.25 cm. The Graflex roll film back that we call 6x9 is actually 3 1/16" wide. I have written about this earlier and it's still confusing.

Flat Top:
Even though I had a lot of fun building the Flat Top, I recommend the use of the Universal and the later lenses, 50mm, 75mm 100mm f3.5 ,black, 127mm, late 150mm black and the 250mm. The only reason I started the project was because the viewfinder/rangefinder was smashed.. The only advantage of a Flat Top is weight and size reduction. Some of the finders one would use on a flat top are really bright with a BIG image which is superior to the dim view finders on any of the Mamiya press models.