If I was to summarize my main complaint about the Polaroid cameras I have, it is that they are all pretty average cameras designed for family snapshots. They all have “normal” lenses of slow aperture, which I find somewhat frustrating. I could use the Bronica and its Polaroid back to shoot in high quality, but then the 6×6 frame only uses half the image area, and is irritatingly plonked right on the bottom edge. What I’d like is a wider angle that fills the frame. For high quality I think the only option would be a Polaroid 600SE, or a Mamiya Universal Press. But those systems would both set me back a pretty hefty sum, so I decided to try a lower quality but super cheap option for getting ultra-wide angle and frame filling shots on peel-apart instant film – a pinhole camera.
I’ve built plenty of pinhole cameras for normal film, and the trickiest bit has always been making it light tight, and still allow me to wind on the film. For peel-apart instant there’s a different requirement – you need something to hold the film pack and allow you to pull the various tabs so that you can squeeze the film between some rollers to spread the chemical sludge and develop the photo. There’s no way I can build something like that myself, so I figured the easiest solution was to find a cheap plastic bodied pack film camera on e-bay and chop the front off and replace it with a pinhole and new shutter.
So that’s what I did – I found myself a second Super Colour Swinger III, exactly the same as the one I already own. When it arrived it wasn’t in great shape, the two batteries still inside had leaked badly and the electrical contacts were very corroded. With a fresh set of batteries there was no sign of life in the shutter assembly, so I felt less bad about the next step. I took a hacksaw and cut through the body of the camera, roughly level with the front of the tripod mount.
I arrived at this length by using Pinhole Designer to calculate the field of view for different pinhole-film distances, and settled on around 35mm, which happily coincided with the point at which the “nose” of the camera juts past the tripod mount.
I smoothed off the edges of the cut and cleaned out the body of plastic filings and flaky crystals from the leaked batteries, then cut piece of black card roughly to size to fit over the now gaping hole and cut a ~10mm square out of the center of this. The pinhole itself was made out of a small bit of an empty Illy coffee can. I made a small dent and then filed down the surface of the dent to make it as thin as possible and then made a hole with the point of a small needle. I measured it with a loupe at about 0.2mm diameter, which is close enough to what I had in mind, so I then taped the pinhole plate over the hole in the card, centring the pinhole itself as best as possible.
The trickiest bit in a pinhole build, I usually find, is the shutter. The shutter needs to be smooth and easy to operate, but must stay lightproof when closed. Having had variable success with pivoting designs in the past, I reverted to a sliding design. Where previously I used card, I was looking for something more resilient this time and my gaze settled on the pile of empty film packs from my PX600 and PX70 experiments. These turn out to be perfect as they are black, smooth, easy to cut, and easy to glue. As a bonus the holes for the battery contacts are exactly the right size and perfectly circular, so make perfect apertures. So the shutter, as seen to the left, is a simple sliding aperture, held in place by overlapping strips, again cut from a film pack.
I hot glued the shutter to the card over the pinhole, and then glued the card/shutter assembly on to the camera body. I went over all the edges with black tape for extra light proofing, and then having cleaned the rollers, remounted the back onto the camera. So now I have a 35mm focal length f/175 camera that makes 73x98mm instant film images. I grabbed a pack of the Polaroid 100 Blue film from the fridge, and the next day before work headed out to test it.
With an aperture of f/175 exposure times are roughly 120 times longer than required for f/16, so with ISO 80 film on a bright sunny day the Sunny-16 rule of thumb suggests around a 2 second exposure. In the morning, conditions weren’t as bright as that, and so I went a couple of stops longer, plus some more to account for reciprocity failure.
Now, normally when testing a new pinhole I have to shoot a whole roll of film, then develop and scan it. This, of course, was different – pull the white tab, pull the black tab, wait and peel. As the temperature was around freezing I tucked the developing film in my inside pocket for a couple of minutes before peeling. The back of the box didn’t go low enough on the temperature chart, so I gave it a couple of minutes extra. The result (right) was just what I’d hoped for. There was a nice wide angle, but with less darkening in the corners than I expected, given a roughly two stop fall off at the extremes due to distance and inevitable vignetting. There are some artifacts which come from the peeling – due to the low temperature I suspect, but that’s all part of the Polaroid fun.
The second shot (left) came out even better – shooting directly into the sun, the image shows some remarkable range. I went out again at lunchtime, and took a couple more, including the image at the top of this post, and they again turned out well. This bodge job is a lot of fun. It’s nice not to have to worry about focus, and the pinhole softness isn’t that noticeable in the prints themselves. The viewfinder – which I couldn’t figure out how to remove – turns out to be surprisingly useful, in that it provides a way of figuring out the centre of the frame. On the whole I’m very pleased with this effort. I have about half a dozen packs of different Polaroid peel-apart films in the fridge, and this should be a great way of shooting it.