I've got a problem with half-finishing projects and losing interest, then never coming back to complete them enough for a good write up. So I guess i'd call this post a bit of a post-mortem even though I got a couple rolls of fresh APS film out of it, and could in theory make more. It's just not as sustainable as I was hoping.
APS film was a photographic film format from the 90s that it seems everyone agrees sucked for one reason or another, except for the thousands of consumers that bought as many cameras during its heyday. Since the film has been out of production for years, ebay is full of the now unwanted tiny and cool cameras. It feels like a great untapped resource in a way that's bothered me for a while.
Reloading empty cassettes seemed possible, and turned out was. But the issue is finding empty cassettes to begin with. A feature of the format was returning the processed negatives in the same cassette it was sold in, which means that there's no reliable source of empty ones other than to buy what's left of expired (and increasingly expensive) unused film.
They did make special replacement cassettes for occasions where the originals were damaged during processing, but for some reason chose to make them out of translucent plastic. Which is a bad omen but more on that later.
There's stuff elsewhere online about opening APS cartidges to extract the film, or details about how the format works, so i'll skip most of that. There's of course actual tools they produced to do this stuff but they're not always available or affordable.
My method to extract the film the film is to fully unwind, hold the spindle at a particular position with the Thing, and then shove the metal tongue in under the emulsion side. The film tends to guide it to the right place, and then the film can be slipped out.
To re-insert film the orange thing is used. The original and nicer version broke and this one was made in a hurry with a lighter and knife. It's funny how reliably it works. You sorta just push the film in and then the tabs on the spindle guide it into place.
So the first attempt at cutting new film was with this device. It worked but not as well as i'd have liked. To minimize handling of the easily scratched film I tried to do every step in the one contraption, while also indexing punched fame holes visually with a sort of DIY night vision made from drone FPV stuff and a sleep mask.
The punch, seen here from below, is made from a bit of case hardened 2mm square mystery steel from ebay. And the die from a chunk of steel filed to shape with about a 1.8mm hole first drilled in to remove the most of the material, a larger hole underneath to relieve it, and then carefully enbiggened with a tiny cold chisel made from more of that case hardened 2mm square steel, and finally by tapping the punch itself through. The die is then also case hardened and ground down a bit on top to produce a sharper edge.
Case hardening is a useful technique but i've only ever had success with a mix of ground charcoal and potassium ferrocyanide, supposedly replicating the old out of production (theme of this post) Kasenit compound. It seems plausible it could liberate cyanide gas at high temperatures however so precautions apply.
This contraption had alot of problems but the real one was this style of slitter. Even with the blades adjusted to just barely cut it still left a wavy edge from the blade squashing the film sideways. The bit for trimming the tail of the film was also not so great. You can buy "APS Reshapers" on ebay occasionally; devices that punch the tail or leader shape out to repair any damage during processing. Waiting for one of those to show up would be the way to go, but old out of production equipment wasn't in the Sustainable Spirit of what I was hoping for with this project.
Despite that the thing was capable of producing a roll of film, but it got a bit tight winding the last bit into the cassette. I figured that was due to the wavy edge increasing the width of the film, since normal current production 35mm film measures the same thickness as the APS film at least as closely as I can measure with a micrometer. So I started making a 2nd different contraption.
Contraption 2 has more of a rotating scissors/ pasta maker sort of slitter, which produces a much better cut but is maybe more difficult to make even with a lathe. It's alot of surfaces to try keep parallel and perpendicular between setups.
The other idea with this machine was to index the punched holes using a stepper motor against the 35mm film's existing sprocket holes, as well as it being a good way to draw the film through the slitter.
It worked okay. I think the design needs more work to make it hook onto the sprocket teeth more reliably. And maybe even a motor on the punch so the whole thing can be automatic and ran in the dark without the stupid goggles. This version was made to a deadline that was approaching alarmingly fast, but worked well enough in the end. Although it was still a bit stiff winding the last bit into the cassette.
The deadline was a trip to Prague to meet a friend. First time I've ever left the UK too. My Prague Review: good public transit, i'm allergic to beer, the buildings look like videogames but not the ones i like.
But yeah the real problem with APS is the cassettes just wear out lol. When the film goes in its pushed over those flexible plastic cups, and what I suspect is happening is the rubbing slowly creates little grooves in the plastic, that then catch further and become bigger grooves till eventually the thing just collapses under the film and gets mangled.
From reading about the format, the conclusion i've come with is that it's main purpose as a product was to rip off photo labs. All the major film manufacturers got together, realising that film was on its last legs, and decided to come up with a new format that would demand photo labs buy new expensive processing equipment to stay in business. Equipment that they'd never be able to recoup the costs from as film sales tapered off.
It's easy to start reading every aspect of the film in bad faith once you decide it was up to no good. Film not processed with the correct machinery (no data written to the mysterious magnetic layer) will cause alot of the various home peripherals to report errors. None of the cameras made for it feel particularly feature complete compared to 35mm equivalents. Maybe the film was only returned in the cassette to deliberately make it difficult to reload or to use film from lesser manufacturers, like a kind of DRM measure. It feels plausible when the only empty spare cassettes made were deliberately not light-proof.
Only the SLRs seem to let you change the film speed settings, and only a couple of the point and shoots let you change the exposure compensation. It's a problem with expired film generally needing to be down rated in speed to get better exposed images.
Only way to change that would be to reprint the "Optical IX" barcode things on the bottom of the cassettes. I figure they're 13 bits read based on how thick each Wedge is, with each wedge alternating in reflective or not, and always a total of 5 wide wedges and 8 narrow ones to balance it out. I had some success making new stickers of known codes with hot foiling techniques, even though the paper I ordered was a bit too textured for a good even Foiling. But I wasn't able to figure out any kind of pattern with the codes outside of the first 3 digits defining the frame count. Either i'm dumb or i'd need a bigger sample.
40@000-NA 001 01011 01000 FUJI SPARE CARTIDGE
25@100-CN 010 10110 00001 KODAK ADVANTIX 100
25@200-CN 010 00011 00011 KODAK ADVANTIX 200
40@200-CN 001 00011 00011 AGFA APS STAR
25@400-CN 010 10011 00001 FUJI NEXIA 400
25@800-CN 010 00111 00001 FUJI QUICKSNAP 800*
25@400-BW 010 10001 10100 KODAK ADVANTIX 400 B&W
15@200-CN 100 00011 00011
*from a disposable camera, only source of an 800iso roll
I could find at short notice. but trying to replicate
this made every camera it was tried in VERY upset.
I think this covers the most of what I did. Here's a messy Sketchup file with the contraption that kinda works. I imagine it's too idiosyncratic to be much use to anyone, but it does have some reasonably accurate dimensions of the APS film itself.
Oh and I kinda ignored the magnetic layer. It's transparent somehow, supposedly, and I got no idea how that works. But I don't think there's much you could do with it now except for changing out film mid-roll and having it remember the last exposed frame. The rest of the features were mostly just to tell photo labs which tacky 90s method to ruin your prints with.
But yeah, without a good source of empty cassettes i'm not sure how seriously i'm gonna continue this. What i've got works Good Enough for the occasional roll. Plus y'know how these things go; most of the interest is just having a bunch of Stuff to look at and read about all day and that is the True Unsustainable Resource.
