Adding a Polaroid Back to a Vintage Film Camera

Even as shooting digitally has made life faster and easier for me in a lot of ways, I've still held on to a handful of film cameras as a personal creative outlet.

In fact, as my work has shifted away from even camera-based projects to using more digital and software-based tools, I've found myself pushed towards older, more esoteric cameras that introduce flaws and an element of unpredictability.

One of my favorite old cameras that I own is this 2x3 Pacemaker Speed Graphic. As near as I can tell, the one I've got is from the mid 40s, but it could be form as late as 1970.

I recently acquired a polaroid back for a Mamiya RZ67, and I thought I'd try frankenstein-ing the two together

Step 1: A Quick Note About Focus...

Even though I'm working with two very specific camera components, this can easily work for a variety of combinations if you keep this in mind:

Take note of where the camera's film plane is. Thats the plane (perpendicular to the lens axis) where the sheet of film sits. Now, also take a look at the film plane of the polaroid back, and the specifics of the case around it.

In a perfect world, you'll have a camera and a polaroid back that somehow magically align in a way where you can get the polaroid's film plane exactly where the camera's original film plane was. If this is the case, then you can probably stop reading. Either they probably already make a polaroid back for your camera, or you can just slap it on there with some gaffer's tape and start shooting.

In the real world, you'll probably have a large discrepancy between where the camera wants the film to be and where you can actually put the film.

In this case, you need to have a camera where the front lens mount is moveable, or else you need to find some way to adjust the lens mount exactly the same amount as the distance between old film plane and the polaroid film plane.

If you can't move the lens mount, you probably can't stick a polaroid back on your camera.

Step 2: Measure!

OK! Let's figure out how to stick one thing to another thing that were definitely never designed to be together.

Remember: Life finds a way.

If you're lucky, you might be able to dig up technical diagrams for your camera or back. That would be great...

Most likely, you'll have to bust out those calipers! A normal ruler just isn't precise enough for what we're doing, especially if you're trying to measure circle diameters.

Honestly, if you learn nothing else from this, please at least leave with the desire to buy at least a cheap set of digital calipers. They'll make your life easier and you'll get immense joy from constantly measuring things and shouting "for science!"

Step 3: Design!

Armed with your precisely measured data, now it's time to figure out how to mate the two pieces. There are several possible roads to go down here.

I strongly suggest working in some sort of 3D software to at least visualize the part you're making.

I'm a big fan of Blender, mainly because I first started using it when I was in high school and the $0 price tag was a big selling point at the time. It can be a counterintuitive and frustrating software, but it's also incredibly powerful.

If you don't know a 3D software, this is a perfect chance to learn. This whole adapter was made with primitive shapes: cubes/rectangles and cylinders. Things that hold film usually need to be more-or-less flat, so you probably won't have to work with any crazy curves.

Step 4: Prototype!

I wanted to test-fit both sides before I made the final part. I split-off the polaroid side into a standalone ring to minimize the amount of material.

I'm using the Form 1 resin-based 3D printer. If I had a CNC mill, I'd use that. If you're really good with wood or metal, that's awesome - maybe there's still something here for you.

If you are 3d printing like me, try to set up any necessary supports on the unimportant surfaces - ie the surfaces away from the thing you're trying to attach to.

Since this was just a test fit, I set my layer height to the maximum possible for a faster print.

Step 5: Prototype Some More!

I was planning on making this half of the adapter out of several layers of laser cut acrylic, since it's all made up of right-angled shapes.

Unfortunately it's still out of commission (new tube hasn't arrived yet) so I decided to cut out the smallest possible section that would let me test the size and 3D print that as well.

End of the day, the resin was getting gunky and old, and it definitely compromised the print quality. I came back the next day to find a partially failed print. That's what you get for cutting corners, kids!

All of the important features are still there though, so it's still useful to test how securely it fits in there.