A bottle is not a film canister

What the archetype says

Poured thin liquids where chemical resistance is the entire decision. That describes darkroom chemistry accurately and describes a film canister not at all.

What a film canister is

A light-tight container sized to a roll of film, usually with a press-fit lid and often opaque by construction rather than by pigment. It holds a dry object and excludes light rather than air or solvent.

Light-tight is not the same as opaque

An amber or black bottle attenuates light; a film canister excludes it, including at the closure. A threaded cap with a liner is a chemical seal and not necessarily a light seal.

And the geometry is wrong

A roll of film is a specific diameter and height, and a bottle neck is narrower than its body. Getting a roll into a bottle is awkward and getting it out in the dark is worse.

So we do not stock one

There is nothing on this shelf or elsewhere in the catalog that is a film canister, and the 16 black and 14 amber bottles here are not substitutes. Saying so is more useful than selling one.

The other three leaves are well served

Darkroom chemical, decanted developer and fixer storage are all poured thin liquids in a chemically resistant bottle, and 191 containers is a wide choice for them.

Which is the honest division

Three of four served properly and one not at all. A shelf that confidently offers the wrong container is worse than one that offers nothing, which is the same conclusion several other properties here reach.

The archetype is right about three leaves and silent on the fourth

Which is a better record than most groups in this library manage. Naming the one it does not fit is cheaper than pretending a bottle will do, and it takes a paragraph.

References