What is...

[electrifyin_ryan]

that lens that directors have around their necks?
The ones they can look through instead of making a rectangle with their fingers.

Sorry if this is big newbie question.

 

[DBXMe2]

its a view finder.. and they use that to see with what lens will give what look..

its mostly for the Director's of Photography.... Directors use it on set because they have final say on the framing... but mainly you would rearly use it, because you should have a story board drawn and on it details of what kind of Depth of field you should have and stuff like that.