FORUMS: list search recent posts

exposure and iris

COW Forums : Cinematography

<< PREVIOUS   •   VIEW ALL   •   PRINT   •   NEXT >>
Justin Leyba
exposure and iris
on Dec 27, 2009 at 6:36:48 am

hey guys! i have a sony hdr-fx7 camera and the exposure and iris are only in 1 control and i always need to change between them in the menu settings. Any tips on when to use the exposure and iris? and how do I use them to make my videos look great and less grainy? thnx!


Return to posts index

Richard Herd
Re: exposure and iris
on Dec 27, 2009 at 5:43:53 pm

The standard calculation is:
[frame rate] * [shutter angle] = Shutter

Consider an example from film: 1/24 fps * 180/360 = 1/48 shutter.

Beyond that calculation, experimentation is your friend.

Trying to run through the various calculations gets cumbersome. For example, 1/24 * 1/x = 1/2000
1/[24x=2000]
x=83.3

1/83.3=y/360
y=4.3 degree shutter

Feel free to check my math.

IMO, you should keep the shutter mostly fixed unless you're doing specific effects (Saving Private Ryan, for example with a narrow shutter). But if the whole movie is that way, then nothing is that way. Make sense?

Video is 1/29.97*1/2=1/60, so that's where a quote-en'-quote "normal" picture should be.



Return to posts index

<< PREVIOUS   •   VIEW ALL   •   PRINT   •   NEXT >>
© 2017 CreativeCOW.net All Rights Reserved
[TOP]