Question about changing f stop exposure for class

[Benco]

Didn't film canisters have a graphical code on them that 'modern' film cameras could read to give them the ISO rating and frame count?

 

[ann]

Yes, they have a dx code, but it can be overhidden with most cameras.

 

[TCampbell]

Didn't film canisters have a graphical code on them that 'modern' film cameras could read to give them the ISO rating and frame count?

I suspect you're thinking of APS cameras. APS is the "Advanced Photo System". It was a film canister with a kind of barcode on the side and a serial number. When a 35mm film canister is developed, the film is completely removed from the canister, developed, cut into strips, put into little protective sleeves, and returned with the prints. When an APS canister is developed, the film is pulled out, developed, and then pulled right back into the original canister/cartridge.

A tiny contact sheet was printed which had the film cartridge number printed in the corner, a thumbnail of all the prints (and index numbers as to which frame on roll has that image) and it all came back in a large-ish envelope.

A photo taken with APS could be printed however you wanted... including panorama.

The "APS" in "APS-C" (DSLRs with APS-C size sensors) is the *same* APS used by APS film. The "C" stood for "Classic" size.

See: Advanced Photo System - Wikipedia, the free encyclopedia

 

[Helen B]

Didn't film canisters have a graphical code on them that 'modern' film cameras could read to give them the ISO rating and frame count?

As ann says, that is the DX code, and it is still used. It is a very simple set of conductive or non-conductive patches on a 135 cassette (the standard 35 mm still film cassette) that tells the camera exactly that information: ISO and number of frames. It could be overridden on most good cameras, but not on many point & shoots. Older cameras did not have DX reading contacts. You could alter the code either DIY or with labels, but obviously not easily for individual exposures part way through a roll.

 

[shyy]

Thank you everyone! I am getting the hang of this now.

 

[BrianV]

Yes, technically you could lie to the camera and report that you've loaded a different speed than is actually in the camera and this would cause the meter to lie to you in return about what setting to use. But why do that? You already know you plan to take the meter's advice for the middle exposure and then deliberately run the camera up and down 3 stops in each direction. Many film photographers can share at least one story where they changed film types, forgot to tell the meter, and shot an entire roll at the wrong setting <sigh> guilty <sigh>.!

This particular camera is the AE-1Program, so changing the ISO setting splits the -3 to +3 bracketing across the F-Stop and Shutter-Speed. The OP stated that the lens could not be opened up enough to compensate on the over-exposure end. Setting the ISO means changing one parameter and allowing the meter to perform the computation in Program mode.

 

[BrianV]

Didn't film canisters have a graphical code on them that 'modern' film cameras could read to give them the ISO rating and frame count?

I suspect you're thinking of APS cameras. APS is the "Advanced Photo System". It was a film canister with a kind of barcode on the side and a serial number. When a 35mm film canister is developed, the film is completely removed from the canister, developed, cut into strips, put into little protective sleeves, and returned with the prints. When an APS canister is developed, the film is pulled out, developed, and then pulled right back into the original canister/cartridge.

35mm Film canisters made since the mid 1980s or so have a code on the film canister that allows the camera to read the ISO automatically via electrical contacts in the film body. The Nikon N8008s and others with similar capability read the ISO speed from the canister and set the exposure meter accordingly. Some cameras allowed you to over-ride the setting, some companies even sold metallic labels for using with non-coded 35mm canisters. Most point-and-shoot 35mm cameras made from the early 1990s had this feature. My Leica Mini and Olympus Stylus set the ISO automatically.

The AE-1P that the OP uses does not read film ISO automatically, and must be manually set.

 

[Benco]

Didn't film canisters have a graphical code on them that 'modern' film cameras could read to give them the ISO rating and frame count?

I suspect you're thinking of APS cameras. APS is the "Advanced Photo System". It was a film canister with a kind of barcode on the side and a serial number. When a 35mm film canister is developed, the film is completely removed from the canister, developed, cut into strips, put into little protective sleeves, and returned with the prints. When an APS canister is developed, the film is pulled out, developed, and then pulled right back into the original canister/cartridge.

A tiny contact sheet was printed which had the film cartridge number printed in the corner, a thumbnail of all the prints (and index numbers as to which frame on roll has that image) and it all came back in a large-ish envelope.

A photo taken with APS could be printed however you wanted... including panorama.

The "APS" in "APS-C" (DSLRs with APS-C size sensors) is the *same* APS used by APS film. The "C" stood for "Classic" size.

See: Advanced Photo System - Wikipedia, the free encyclopedia

I was actually thinking of 35mm film, Thanks for the interesting info on the APS cameras though. I'd never got into using that system at all so know eff all about it.