• Cinematography

  exposure and iris

  Posted by Justin Leyba on December 27, 2009 at 6:36 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!

  Richard Herd replied 16 years, 4 months ago 2 Members · 1 Reply
• 1 Reply

• 

  Richard Herd

  December 27, 2009 at 5:43 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.

Reply to this Discussion! Login or Sign Up