Paterson Changing Bag — Large .

You need a changing bag every time you load film into a developing tank. This is the one to get.

The large size gives you actual room to work. Your hands can move freely, you can feel what you're doing, and loading a reel doesn't become a fight against the fabric. The double-skin construction with double zip keeps light out — there's no single point of failure. The arm openings are elasticised so they seal around your wrists without cutting off circulation.

700 × 700mm is big enough to open a medium format camera back inside, not just load 35mm. If you shoot 120, that matters.

It's also useful outside the darkroom context — if a roll jams in a camera or you need to rescue film in the field, a changing bag handles it. Keep it with your kit.