Disc Film,When Kodak Pushed Convenience Too Far
Having a penchant for cheap second-hand cameras can lead to all manner of interesting equipment. You never know what the next second-hand store will provide, and thus everything from good quality rangefinders an SLRs to handheld snapshot cameras can be yours for what is often a very acceptable price. Most old cameras can use modern film in some way, wither directly or through some manner of adapter, but there is one format that has no modern equivalent and for which refilling a cartridge might be difficult. I’m talking about Kodak’s Disc, the super-compact and convenient snapshot cameras which were their Next Big Thing in the early 1980s. In finding out its history and ultimate fate, I’m surprised to find that it introduced some photographic technologies we all still use today.
Easy Photography For The 1980s
Since their inception, Kodak specialised in easy-to-use consumer cameras and films. While almost all the film formats you can think of were created by the company, their quest was always for a super-convenient product which didn’t require any fiddling about to take photographs. By the 1960s this had given us all-in-one cartridge films and cameras such as the Instamatic series, but their enclosed rolls of conventional film made them bulkier than required. The new camera and film system for the 1980s would replace roll film entirely, replacing it with a disc of film that would be rotated between shots to line up the lens on an new unexposed part of its surface. Thus the film cartridge would be compact and thinner than any other, and the cameras could be smaller, thinner, and lighter too. The Disc format was launched in 1982, and the glossy TV adverts extolled both the svelteness of the cameras and the advanced technology they contained.
The film disc is about 65mm in diameter, with sixteen 10x8mm exposures spaced at every 24 degrees of rotation round its edge. It has a much thicker acetate backing than the more flexible roll film, with a set of sprocket-hole-like cutouts round its edge and a moulded plastic centre boss. The cassette is quite complex, having a protective low friction layer and a vacuum-formed lightproof film window cover and disc advancer inside the two injection moulded halves. Meanwhile the image size is significantly smaller than that of the 16mm 110 cartridge film or a 35mm frame, meaning that Disc films were the first to be released with Kodak’s new higher-resolution tabular grain emulsion. This film had the silver halide crystals aligned flat on the substrate, reducing light scattering.
Turning to the camera, for teardown purposes here we have a battered old Kodak 4000. This was the slightly fancier of the disc cameras at launch, but now they can easily be found for pennies in thrift stores. Opening it up is a case of gently easing the aluminum front panel away from the body, revealing all the internals. Once inside the camera, everything is automatic. On the left is the xenon flash tube, the flash capacitor, and a pair of Matsushita lithium batteries, in the middle the circuit board covered by a high voltage warning sticker, and on the right are the mechanical parts. If you teardown one of these for yourself, you’ll want to disconnect the battery as we did, and discharge that flash capacitor. Even four-decade-old lithium batteries can hold enough capacity to charge it, and at 200 volts it packs a punch.
A Lot Of Complexity For A Simple Product
Carefully unsoldering the connections and lifting the board from the camera, we find a mixture of through-hole and surface-mount parts. The flash circuit is conventional, a small single transistor inverter that’s responsible for the “Wheeee” sound you hear when cameras of that era are turned on. The rest of the circuit is interesting, because all the control and light metering circuitry is driven by an integrated circuit. Marked “ACP 152”, it has no makers mark other than stating it was manufactured in Malaysia, and all manner of online searches on the part number reveal nothing. If this camera had been made in 2002 it would certainly be a microcontroller, but in 1982 such a conclusion would be much less likely and would certainly have been central to their marketing if present. Looking at its support components I see no clock circuit or other likely microcontroller ancillaries, so my best guess is it’s an ASIC containing analogue and logic circuitry, forming part of a simple state machine along with the electromechanical cam arrangement in the mechanism.
On the right a small motor turns a wheel (the blue plastic part in the photographs) with that selection of cams that open the window in the film cartridge and cock the shutter, for which the release is electronic via a small electromagnet. One of the functions is to push up a pin which lifts part of the film window cover clear of its locking protrusion, allowing the film to be advanced and the window opened. The lens doesn’t look special but in fact it’s the part which has most relevance to some of the cameras you’ll use today, because it’s the first mass-produced aspherical plastic lens. To deliver as sharp an image as possible on the smaller negative they needed a lens which would minimise aberations, and given the compact size of the camera they couldn’t have a multi-element lens that poked out of the front. This was the solution, and it’s a technology that has had a massive effect on miniature cameras ever since.
Where They Pushed Convenience Too Far
Looking for the first time at the workings of a Disc camera then, it’s a beautiful piece of miniaturisation, but it’s undeniably a complex mechanism when compared to the Instamatic 126 cameras it replaced or the 35mm compact cameras which competed with it. The specialist electronics, the electronic shutter release, and all those mechanical parts are impressive, but there’s a lot in there for a consumer snapshot camera. In doing this teardown we start for the first time to gain an inkling of why the disc format never achieved the success Kodak evidently hoped for it, though it’s when we consider a typical Disc photo that the real reason for its failure emerges.
The Disc’s tiny negative, when combined with the high-resolution film, gave a good quality image. But in those days when photographic prints were the medium through which people consumed their pictures, it was a this smaller negative which led to lower quality enlargements. To solve this problem Kodak sold a complete printing package to laboratories with an enlarger system specifically for Disc film, but many laboratories chose to use their existing equipment instead. The result was that the new cameras often generated disappointing-quality prints. By comparison a 35mm snapshot camera gave a much higher quality and had 36 pictures on a roll of film, so for all its sophistication and innovation the Disc format was not a success. By the 1990s the cameras were gone, and the film followed some time around the millennium. Kodak would try one last shot at ultimate film convenience in the mid 1990s with the Advanced Photo System, but by then the digital camera revolution was well under way.
Looking at the Disc camera here in 2024, it’s clearly a well designed item both mechanically and aesthetically. I have three of them on my bench, they still look sleek, and amazingly those four-decade-old lithium batteries still have enough power to run them. With hindsight it’s easy to say that its shortcomings should have been obvious, but I remember at the time they were seen as futuristic and the way forward. I didn’t buy one though, perhaps it says it all that they were way outside pocket-money prices. Maybe the real insight comes in using Disc to explain why Kodak are now a shadow of their former self; when the reason for extreme convenience in film photography was eclipsed by digital cameras they had nothing else to offer.