A Look at the Clever Automation of Film Cameras

We take a lot for granted in the digital era, particularly the automation of a lot of functions. In the early days of film, everything was fully manual, and even one parameter set incorrectly could ruin an entire roll. Later in the 20th century, a standard called DX (Digital indeX) was introduced, and it automated a lot of settings, reducing errors and making photography more accessible to amateurs and casual users. How did it work? This neat video takes you behind the scenes of the surprisingly sophisticated system. 

Coming to you from Technology Connections, this interesting video will show you how DX film encoding worked. First introduced by Kodak in 1983, the DX system had multiple parts: a barcode on the edge of the film strip below the sprocket holes, encoding on the cartridge itself, and a barcode used for developing. While the DX system was tremendously useful for photo developers, it also made photography easier by automating a lot of things. A camera capable of reading DX encoding could automatically set the ISO, exposure count, and exposure tolerance when a cartridge was inserted in the camera. This might seem minor, but if you forgot to set the ISO, you could over- or underexpose an entire roll. On top of that, knowing exactly how many exposures you had left was always useful, and having exposure tolerance settings was great for cameras with advanced functions. Check out the video above for the full rundown. 

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4 Comments
Benoit .'s picture

Detect developing times? Science fiction. Both C41 and E6 film have specific processing times and no machine can detect from the canister if you over or under exposed. So that leaves the "auto detect" with no magic power (no need). If it's Western Color negative, it will go in a C41 bath and if it's not Kodachrome, then positive will be E6 (all brands use the same process even if the brand didn't call it E6. It would mention E6 compatible). Other Eastern positives color rolls or negatives had their own process, with labs hard to find. While most C-41 processors could actually push or pull, almost all techs had no clue what this was about and that the machines had that option.
A very large quantity of film would be processed at night in major labs, 10k, 50k or more rolls night. These where queued to form a spool maximizing the use of automation. From the client drop off the envelop would have an envelope with a unique barcode. When the tech scanned the envelope as he/she removed the canister to drop it in the machine, a matching code would be generated so in the end, the set of prints would be automatically sorted to match the film and both packed to fit back in the original envelope to be returned to the client. The group of envelopes would follow the spool by being passed from tech to tech for each step. There were no option to push or pull when the rolls would be processed from a spool with 40 -50 other rolls.
Some of those giant labs would have dip and dunk for E6, some would spool positive film the same way as C41 offering no push pull option. Typically if your negative or positive roll was processed in a spool, you would end up with a barcode on the film that is back in your envelope. The cut strips could kind of have a variations in the number of frames on each strip and you would get a tiny portion of the next client's roll attached where the barcode was.
Personally I have never seen an automated processing for black and white and I don't think the volume was worth making machines that would sort b&w by type of film and specific processing time. Most if not all dip and dunk machines, no matter if b&w, color negative or color positive would allow for push or pull, but no canister detection either.

Andy Harding's picture

I worked for a large commercial lab in UK for 14 years and Denoit is spot on process was:-

In via our vans from chemist shops/photographic shops around the country then Splicer Machine > into large cassette (usually 303 films on a cassette) > Film Processor > Notcher > Printer > Paper Process > Finishing (prints and negs cut and put back in envelope) and priced then shipping back to customer via van / post.

We did anything between 4500 (Winter) to nearly 50K Summer day after a bank holiday.
I worked from print room to head of finishing department in my time there. Met my partner there as well :-)

Benoit .'s picture

What was the most common location you saw on the prints coming from the dryer? I worked a summer at a Fuji lab in France, and by far, the Niagara Falls from the Canadian side was the most repeat night after night. Really, I was very surprised by the location.

Jan Steinman's picture

Anyone who's been on GuruShots.com would not be surprised. :-)