Saturday, November 24, 2018

Variable Cuboid Mid-Mission Review

I’ve completed a second copy of the Variable Cuboid Pinhole Camera System and subjected it to testing. The system meets many of its objectives but some disclaimers are necessary where it misses expectations.

One defining feature of a camera system is that parts interchange between individual copies and I’m afraid, the hand-made Variable Cuboid can’t manage the tolerances to reliably achieve this interchangeability. The new camera back is about a millimeter larger than the original. The older fronts just won’t make it over the new back. With all my cameras, in order to make the joint between the front and back invulnerable to light sneaking through, I’ve always made the outer box by clamping it around the inner one when they are glued together. If the custom fit is tight enough to prevent light leaks in the camera it was originally made for, it just won’t go together if the new outside box is even slightly smaller than the original. Even with a flexible material like cardboard.

So you can make fronts of many different lengths for a specific back but your likelihood of making two backs the same size is basically random chance.

I made the second copy without comparing it to the first. I’m going to try to make another back measuring it against the last one, adjusting it at every step and see if it's possible to get them to fit interchangeably.

I make cameras to use myself but a goal has always been that the design was easy enough for anyone with minimal skills to make. I just made a 35mm Populist and it’s really easy. I may have crossed a line with the Variable Cuboid. It uses most of the same methods but to put it bluntly it’s harder to make. It has more parts, more layers, more specific clamping methods, numerous round holes to cut and numerous times where it’s necessary to wait until the glue is completely cured to continue.  I didn’t have any trouble with any of it but it might not be the best project to start with.

On the positive side, it meets the objective of being able to change the distance to the pinhole at any time without having to wait until the end of a roll of film. It does require a darkroom or changing bag to make the change. Making this change of length in the daylight would be difficult to accomplish with my cardboard, glue and scissors repertoire.

From my point of view, needing to go into the dark to change the length of the camera isn’t a big deal. I have a darkroom and changing bag. In actual practice I rarely shoot a complete roll in one outing and I kind of like the game of having a certain angle of view and hunting for scenes to take advantage of that length but it's also nice not having to finish the roll to play with something else. I did enjoy being able to use the wide angle for interiors and the long front for a walk around the neighborhood.

It was a pleasure to use. The finders were easy to see and line up. The film advanced smoothly. I glued wine corks around the wooden dowels to make an easier-to-grip winder. Like everything else with this camera, loading it requires a specific procedure, but once you learn it, it isn’t that hard.

I made two fronts for it, a 35mm with .25mm pinholes at f140 (optimal according to Mr. Pinhole) and a 100mm with .35mm pinholes at f286 (about 83% of optimum)

But the best part of building cameras is the user experience testing.

As soon as it was finished, with the 35mm mounted, I pointed it at an old standby, the south window in our kitchen using the on-axis pinhole.

The next morning, another trusty subject, the pothos above the bathtub, with the rising pinhole.

Later that afternoon, I changed to the 100mm and went out for a walk with the winter sun low in the western sky.

The bare giant oaks at the end of the soccer field casting their shadow onto the equipment sheds. After visiting Edward Gorey’s home on Cape Cod, I’ve been reading his anthologies. I think it’s starting to get to me. Rising front pinhole.

The white soccer goals spotlit by a sunbeam between the houses. On-axis pinhole

A tree, it’s shadow and another tree’s shadow against the Merrill Elementary Gym with the bicycle rack giving us a great big grin. Rising front pinhole 

There are two kindergarten rooms at Merrill School. On my inaugural ride with Goldberry, I depicted Andy’s sun-drenched kindergarten with storybook floor-to-ceiling, leaded-glass bay windows. This is the other kindergarten room. I think it might be from a different story. Rising front pinhole.

There was a waxing gibbous moon rising. I took this picture just to try to get it on film. It’s the fuzzy highlight just off the edges of the tree branches. Amazing to think the earth rotated enough to give it a little bit of a smear in the three minutes the shutter was open. Rising front pinhole.

I went around the building to try again and caught the last sunbeam illuminating the top of the middle school. It was pretty dim by now and the moon and the sky got overexposed while the negative gathered photons from the shadows. On-axis pinhole. (The camera is next to the elementary gym which is a little uphill from the middle school)

When I got back home, I put the 35mm front back on and made shepherd’s pie. I’m in front of the camera during almost the entirety of the half hour exposure.You can see lots of my utensils and ingredients, but I’m just a shadow on the cabinets. On-axis pinhole

The pie in the toaster oven. It only baked during a third of the 90 minute exposure. I was hoping there would be sort of a glow from the inside of the oven, but dinner would probably burn if it had been on during the whole exposure. On-axis pinhole

The next day, I had to go downtown early in the morning. I left the shorter front on the camera. This is the intersection of Church and Main. Rising front pinhole 

All summer I’ve been meaning to photograph the back of the Frontenac Flats, another work by ubiquitous Oshkosh architect William Waters. (The back of the building on the right in the previous photo is his also.) The front of the building on the corner of Brown and High Streets is a prime example of his neo-Romanesque style but this back view shows his attention to providing daylighting for the residents. Rising front pinhole.

All with 100 developed in Rodinal 1:50

It was a little discouraging when I discovered the parts wouldn't interchange between the new and the old Cuboids but I've recovered a bit after shooting a roll of film with it. It was also encouraging to see on Twitter that fellow midwesterner David Johnson had made one of my cameras. I don't hear that very often. I've already taken most of the pictures so I'll probably do a building-of post.

But you've been warned.


  1. I always enjoy your posts, especially about refining your camera systems. Have you considered a book? I'd buy it for sure.

  2. I like making picture books, but I don't think that's what you're referring to. I'd love to do this if some publisher wanted to give me a lot of money, editorial and design support and not argue with me too much.