iris (exposure) settings

Iris (Exposure)
The IRIS is an adjustable ring that controls the amount of light coming into the camera. Iris (or aperture) is measured in f-stops. The smaller the number, the larger the opening.
ADJUSTING the IRIS
  1. Make sure your camera is in MANU(al) mode.
  2. Press the IRIS A/M button to switch to manual iris mode.
  3. If you see “STD” on the display, it means you're in AUTO IRIS mode. You don't want that. Press the IRIS A/M button until "STD" disappears from the display. When it does, you’ll see the word OPEN or an f-stop number (like F9.6 or whatever).
  1. Turn the iris ring (see picture) to adjust the iris setting.
  2. The current f-stop measurement will likely appear on the LCD screen (even if it doesn’t, the camera’s image should get darker and lighter).
  3. When the iris is adjusted to go brighter than OPEN, the gain value (measured in dB) will appear below the white balance indicator.

Histogram

There are two cool features to help you judge the exposure: Histogram and Zebras.

  • A HISTOGRAM is a graph that shows the range of values in the viewfinder. Ideally the peak of the histogram should be centered and completely inside the box (not a cut off on either side). 
  • To turn HISTOGRAM on/off, touch the screen and press HIST.

zebras

  • ZEBRAS. Push the ZEBRA button once and you’ll see wavy lines across areas above 80% brightness.
  • Press it twice and you’ll see those lines across areas above 100% (totally over-exposed areas). If you see any zebras on the 100% setting, turn the iris to remove them. But watch the histogram: if there’s a bright light or window in the shot, it might be impossible (undesirable) to remove all the zebras.