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Symbolic Forest

A homage to loading screens.

Blog : Posts tagged with ‘pinhole cameras’

In the footsteps of Fox Talbot (part three)

Or, some cardboard engineering

Another weekend, more work on the papercraft pinhole camera kit I’ve slowly been working on. If you haven’t seen the previous installments, part one is here and part two is there.

This time, I spent most of the time on some of the cosmetic detailing. I glued on a whole set of fake camera controls: shutter button, wind-on lever, timer lever and lens mount release button. They’re not the neatest job, but they’re only there to make the thing look like a camera, so it doesn’t really matter if I don’t get them quite right. More important is the film take-up spool, which I’m trying to assemble very carefully and slowly because, fundamentally, it has to work mechanically as well as look good.

Camera so far

On that photo you should be able to make out that the take-up spool looks as if it has an extra lamination. That’s a strip of card added and only glued at the ends. The idea is, the leader is slipped between that strip and the main part of the take-up spool, and that (with a few turns of the spool) that should be enough to hold the film in place. I’m intrigued how well it’s going to work.

The other part I made up that is fundamental to the camera’s workings is the camera back

Camera back

Given that if the back comes off at the wrong time the whole thing is useless, and that the integrity of the back relies on four small corner tabs, I thought it worth holding the whole thing together with foldback clips whilst the glue did its thing. Normally I’d just rely on a good firm squeeze between finger and thumb, but this seemed rather more important. I suspect I’ll end up taping the back on with something like washi tape when the camera is loaded in any case, because it’s going to be a fine line between a back that’s too tight to go on properly and a back that’s so slack it falls off.

I’m not sure this camera was really designed to run more than one film through it anyway: as I said last time, the instructions tell you to take the whole thing to your local photography lab rather than try to unload the film yourself. Which would seem a bit of a shame, because how are you supposed to learn from your mistakes with a new camera, and learn how it behaves, if you basically have to throw it away before you get the results back? Hopefully it will cope with at least a couple of films before the back falls apart.

In the footsteps of Fox Talbot (part two)

Or, recovering from mistakes

At the weekend, I did a bit more work on the papercraft pinhole camera I posted about the other week.

Camera, from behind

Can you see the mistake I made near the start, but didn’t realise until everything was set truly firm and solid? The dashed lines marked on the card are a bit of a clue. The entire central portion of the body is upside-down. Because the film passes through the body off-centre, this means that the frame mask is in the wrong place: it’s about 3mm or so too high. The photos this camera takes are going to have their bottom sprocket holes exposed, but (unless I take a scalpel to the frame mask) will have a black band along the top. Oh well: it’s not as if they were ever going to be perfect photos in any case. I did, at least, realise this before sticking on the film guide rails, because if I’d put those the wrong way round, with the fat one at the bottom and the thin one at the top, the camera would be completely unusable. As a 35mm film canister is handed, they have to be the right way round for the film to slot properly into place. Luckily, I decided to measure up the guide rails against the leader of a new film, and immediately realised what I’d already got wrong.

Camera, from the front

The next step is the takeup reel, which worries me because, even more so than the “shutter”, it’s the one part of the camera that’s made from card but needs to function mechanically. It feels as if the tolerances in this part of the machine are quite tight, which should hopefully help, so long as they’re not too tight that it takes a camera-destroying force to turn the wind-on knob. You can see that in these pictures: a hollow card hexagon which I would imagine is quite easily distorted if the wind-on action is a bit stiff.

Incidentally this camera has no sort of rewind mechanism. The instructions suggest you take it to a photography shop to get the film out again after it’s exposed. Luckily, I have a changing bag I can use to do it myself.

The next update on this project is here.

In the footsteps of Fox Talbot (part one)

Or, going back to the early days

The Child Who Likes Animals is a great devourer of television, particularly documentaries, and can recite great swathes of the hours of television he has watched. Usually this involves things about his usual interests, such as animals, or palaeontology, or Brian Cox talking about planets. Recently, though he’s rediscovered a CBBC series from a few years ago that has recently been repeated: Absolute Genius with Dick and Dom, in which said presenters learn about great STEM figures from history. He was rather taken with the episodes on Darwin (naturally), the Herschels, and Delia Derbyshire;* but became particularly obsessed with the inventor of the photographic negative, Henry Fox Talbot. In that one, Dick and Dom build a pinhole camera out of an industrial-size wheelie-bin, making it into a binhole camera; the episode is worth it for that pun alone. The Child Who Likes Animals, naturally, wanted us to build our own.

Making one quite that large, I pointed out, wouldn’t really be practical for taking around the place; but pinhole cameras themselves aren’t that hard to build. In fact, as it turned out, we had a papercraft one already lurking in the rainy-day-activities cupboard. Naturally I would have to do most of the building work, but why not get started?

The starting point

The instructions on the packet said it could be built in as little as two hours. If you use some sort of instant-setting impact glue that might be possible, but with standard PVA (the packaging recommended “white glue”) I suspect it will take rather a lot longer, given how sensible it is to stop and let things set properly between steps.

Folding up the innermost box

As expected, not only did I end up doing all of the building work, but The Children rapidly disappeared to go and watch a film or something. In theory, though, you would think a pinhole camera would be an ideal subject for papercraft, because all cameras are essentially just a black box with a hole (or lens) at one end and something light-sensitive at the other. This build seems largely to consist of folding up a few card boxes, gluing them together, and attaching a fiddly-looking but entirely cosmetic fake pentaprism housing on top. By the time it’s finished, I suspect it will end up 75% PVA by weight.

Folding up the takeup spindle housing, with a lot of excess glue

There are two potential issues I can see with the whole thing. Firstly, building a working and light-tight takeup spindle out of card is going to be a very fiddly exercise which might well prove to be the Achilles Heel of the project. Secondly, there are a couple of card edges that the film has to pass over, emulsion-side down, and I can imagine them scratching the emulsion to buggery. Oh well, I wasn’t exactly expecting it to take pin-sharp perfect results in any case.

The basic carcass of the thing

I have to admit that previous papercraft projects have foundered, incomplete, after one or two building sessions. Hopefully given that this thing is at least intended to produce something usable, I’ll manage to get it finished to the point of being able to put a film through it. Whether anything will be visible on the film afterwards (and whether The Child Who Likes Animals will actually want to use it) is another story. I’ll keep you posted.

The next update on this project is here. Part three is here.

* Personally I rather liked the episode about James Watt, which featured the Newcomen Engine at the Black Country Living Museum, the Crofton Pumping Engine, and a few brief moments of the Severn Valley Railway’s Stanier Mogul 42968 at Kidderminster.