f/stopblues said:
I guess I assumed wrong on these cameras. Do the film spools sit top and bottom then, instead of side to side? I guess this would be like the difference between my C330 and GS-1. Learn something new every day 🙂
Hi Chris -- 645 is a "half frame" format like 35mm half frame, only it's half the frame of 6x9... With your typical 35mm camera the film runs through left to right and the film frame is long in the same direction as the film, right? Same with 6x9... Now with half frame 35, you're still using the full 24mm of the frame but only 17-18mm in the long direction instead of 36mm, half the frame. Now when you still hold the camera horizontally (and the film running left-to-right) you get a vertical frame, 24mm high and 17+mm wide. And 72 shots on a roll of 36.
Same with 6x4.5cm RF cameras; you still get the 6cm but the 9cm direction is cut to 4.5cm. So you get twice as many shots on the roll (16 instead of 8 on 120 film), and for cameras with the film running horizontally, you get a vertical picture orientation.
But TLRs like your Mamiya C330 run the film vertically, bottom to top... and so does the typical 6x6 like the Hasselblad and 645 SLRs like the Mamiya and Pentax 645s. So these 645 guys get a horizontal frame orientation, still crossways to the film. I think there were a couple of 35mm half-frames that ran the film vertically too, like a movie camera.
Some folks like the square 6x6 format because you don't ever have to turn the camera on its side! There have been square 35's too, like the Robot and Tenax. I don't know about the GS-1 (6x7cm?), but the Mamiya RB and RZ can rotate their back to either vertical or horizontal framing. My big Pentax 67 runs its film left to right, so normally has horizontal picture orientation, like a giant 35 SLR, and gets 10 shots on a 120 roll.
Hope this makes sense... One of my first cameras back in the early 60's was a Petri half-frame, later I had an Olympus Pen D2, and I have some Pen F SLRs, so I'm used to the vertical framing, and it's easy for me to see that the 645 format is in a very similar situation too.