Thank you! As I was typing it I knew I didn't have the right term for the ring bit.
I'm going to ignore the fact I could have easily looked it up to fact check myself before posting, and instead use my age as an excuse.
I was just old enough to remember my teachers using them, but the tech was already outdated so it's not like anyone ever taught me about that type of projector, I only ever observed it.
It's always been called a carousel. A deck is the deck of slides like a deck of cards.
Certain slight projectors used straight slide holders, not circular ones. That's probably where the term originated.
https://c7.alamy.com/comp/C3R700/slide-magazine-isolated-over-white-C3R700.jpg
Thank you! As I was typing it I knew I didn't have the right term for the ring bit.
I'm going to ignore the fact I could have easily looked it up to fact check myself before posting, and instead use my age as an excuse.
I was just old enough to remember my teachers using them, but the tech was already outdated so it's not like anyone ever taught me about that type of projector, I only ever observed it.