I just tried posting this in the "Comments" section on the main page under the articles on Filmholders, but got an SQL error, so since there is nothing on Kinematic filmholders on the site as far as I can tell, I thought I'd post it here in the forum. I'd be interested in hearing anyone else's experience with the Kinematic holder:
Another holder that isn't mentioned here is the Kinematic filmholder, which functions like a Grafmatic but holds 10 sheets. I just acquired one of these, and it's interesting--not as well made as a Grafmatic, but seems functional, and it does hold 10 sheets and is only slightly thicker than a 6-sheet Grafmatic. It has a frame counter, but not a wheel to imprint the frame number on the film. It loads much like a Grafmatic.
To use it, there are two handles, a metal one in front (the lens side) connected to the darkslide and a plastic one in back that pulls the box and the frame counter. To expose a sheet with the back attached to the camera, pull the darkslide (metal handle) and re-insert, and you'll see a red line on the back of the darkslide. Expose the film and then with the thumb pull the plastic handle to pull out the box with the darkslide, and allow the exposed sheet to fall to the back of the stack, then release the plastic handle allowing a triangular metal tab to pop up on the top, and push the two tabs in together. If the metal tab does not pop up, the frame counter will not advance (you can then advance it manually by turning the wheel).
Be careful when pulling out the box containing the stack not to pull too hard. The build quality of a Kinematic seems a little lighter than a Grafmatic, and there is some danger that if the stops inside are worn or if the holder is a little bent out of shape, that the box will be pulled too far, and the sheet just exposed will not go back into the stack properly (i.e., it could get caught between the wall of the holder and the box--which has happened to me, or it could jam, or at the very worst you could pull the whole box out and watch all ten septums go flying--which has not happened to me, but I could see how it might). That said, the Kinematic seems a little more positive in operation when loaded into the camera than when experimenting with it off the camera, because the camera back reinforces the structure of the holder.
It will slip under a spring back if there is enough clearance for a Grafmatic, or it can be held by the slides on a Graflok type back.
If something does go wrong, they are not difficult to disassemble and figure out what is out of whack.