Calumet C-1

I just got a green magnesium C-1 and it is very light and relatively easy to work with. I'm mostly using mine in the studio with a Kodak Commercial Ektar 14", so I have no problems reaching the ground glass to focus with the rail extended. If anything, I feel like it is a touch wobbly, and not as locked-down as my Shen-Hao 4x5, but then my Shen Hao is 2 years old, whereas the C-1 is about 35 years old. I got an old Gitzo pan/tilt head with a huge platform, quite inexpensively, at B&H, and it fit quite well onto a set of JTL legs that I have used for my 4x5. In the studio, this seems to be more than adequate to support the weight. I'll keep you posted of my progress with it.

Scott-
I shoot both a Shen-Hao 4x5 and a Calumet C1 "Green Monster". Both lock down solidly on my tripod; I would assume your problem is that either your tripod or your tripod head is under-rated for the weight of the C1.

Try removing the head from the tripod and mounting the camera directly on the tripod. See if it still feels wobbly there. If not, then you know the problem is the head. If it's still wobbly, you might try setting it up on a cinder block to see if it still feels wobbly. If it's not wobbly on the cinder block, then your tripod is not up to the task. If it is still not solid, then it's time to start examining the camera to find out what needs to be tightened down.

The C1 is a very substantial camera, but if it's in good shape it is easily the most solid camera that I've ever worked with. FYI, I use a Berlebach 3032 tripod. I set up the C1 on the integrated ball head. With this setup, I can extend the bellows all of the way out with a Nikkor 480mm f/9 process lens and a Packard shutter on the front standard, and the whole setup is rock solid. I've used the camera this way in a stiff breeze with no problems. Even at the age of the C1, I find it to be an absolutely solid camera.

One other possiblity just crossed my mind: You are centering the weight of the camera over the tripod, right? The tripod mounting block on the camera can be loosened and the whole camera can be moved back-and-forth over the tripod. Make sure the mounting block is near the center of gravity of the camera/lens combination with the bellows extended. No tripod in the world is going to hold the C1 steady if you leave the tripod block in it's "stored" position.

Be well.