I've managed to figure out most of the easy features of the lens, where the f-stop is, etc., but one of the extra barrels they added on (for fun, I guess) I still can't figure out. It's the bottom one, and it has a small lens on the end, as well as an aperture ring that also affects a sliding chart that lines film speeds up with frame rates (I'm assuming). I have a hunch that it may be somehow related to light compensation for increasing/decreasing frame rates, but I can't be sure. Even if I guessed right, I still need advice on how to use this feature, when to use it, if I should just chop it off with a saw, all that. Also, there's a tiny silver button on the same barrel, and I have no clue what it does.
In short, please tell me everything I need to know about this part of my lens, before I do something stupid like shooting a project with it.
Use little words, and assume I know nothing at all about anything film-related. I feel that I'll learn more this way.
EDIT:: Camera is a Rex4 Bolex. Don't know if this is significant, but felt like adding it just to make sure.
Edited by Cinemabun, 13 March 2006 - 01:25 AM.