A Sony PMW-EX1R is set to manual, but the iris keep changing
On the Sony PMW-EX1R and some other digital video cameras, you must be sure that ALL OF THE MANUAL ADJUSTMENT icons are active if you want to have full manual control over your camera.
Iris, Gain, Shutter Speed and White balance settings and icons must all be in seen along the bottom of the screen. Do this by pushing the corresponding Iris, Gain, Shutter Speed and White balance buttons on the camera.
Here is why
The camera software assumes that any parameter that you don't see on the screen must be automatically adjusted by the camera. For example, if you have all of these settings active except the GAIN, the camera will automatically make a gain level adjustment for you when the picture is too dark. Even though you have control of the IRIS, it appears to be adjusting the light level automatically when panning to dark area of the scene.
It's not the IRIS that is automatically adjusting here, it's the GAIN.
Finally, remember, "locking" the manual adjustments by sliding the switch to the HOLD position locks out ALL the adjustments, including the iris, which is the one thing that you usually need to have control over.
© 2013 Pieter de Vries ACS