This memo will describe an example of how to set and check the Auto Iris settings when an HDK-series camera is used with an OCP-200.
With regard to the auto iris response speed, there are now adjustments on both the camera and lens side. In the past the iris gain on the lens was often set low (nearly CCW) to prevent hunting. Now that the camera can also reduce the speed, it is suggested to start with the iris gain on the lens set to a more mid-range position.
The gain on the camera side is set in the camera head menu (Main Menu page 3/3). Go to "Auto Iris Set" and turn "Iris Set Mode" ON. Then scroll to "Iris Gain" and set to 70, set "Iris Speed" to 70. Turn Iris Set Mode Off and exit the camera menu.
On the OCP-200, press the "M" button and then press "Others" soft-key. Place the Iris joystick in mid-position. Select "Auto Iris". Turn on the "Iris Set Mode" soft-key and check for Iris movement. If the iris moves more than 1/2 an f stop, the OCP-200 needs to be initialized. Please refer to the OCP-200 Operation Manual for the "Initial Factory Set" procedure. After initialization, the panel CCU assignment will need to be set.
Set the "Peak Ratio" to -80. Then adjust "Level" to the desired exposure.
Set the lighting and ND filter for approximately an f11 exposure (f10 -f15 is OK). Cap the camera, the lens iris should move to wide open. When you un-cap the camera, count how long it takes for the iris to stop moving and settle at an exposure. A good time is about 3 seconds and there should be no hunting or overshoot. If the time is not right or there is some hunting, set the Iris gain for correct motion. It is recommended to make this adjustment on the lens although some change to the camera menu setting of iris gain is also possible.
The "Peak Ratio" setting will determine how much area of the picture will need to be over-exposed before the Auto Iris begins to stop down. The -80 setting will result in the auto iris system responding only to average picture level, and is a good start for many applications. If the white areas of the picture are small and need correct exposure, this Peak Ratio needs to be increased (more positive).
