The position and size of the windows can be varied by independent front panel controls, and is delineated in white in the televised scene.

The video photometric analyzer is used online, interposed between a standard video camera (525 lines, 30 fps, 2:1 positive interlace, 1 volt black to white) and a video monitor. It is also used with other standard video sources such as tape recorders and discs.

Independent front panel control of X-Y position of each window. Window width and height independently variable.

Frequency response to changes in televised scene light level linear from DC to 20 Hz.

Joystick position control provided.

Gray scale resolution one part in 200.

Analog output.

Features characters on the video screen that can be calibrated to indicate distance between the two windows.

External analog drives for X and Y window position (can be used for automatic window scanning).

External analog outputs for X and Y window position (can be used to indicate window position coordinates)

• Event detection.
• Time of flight (velocity) of moving objects.
• Thickness gauging of translucent specimens.
• Optical density comparison.

• Blood flow rate from dye bolus transit time.
• Lung perfusion mapping, pulsatile and nonpulsatile.
• Renal dye washout curves. Flux of red blood cells in capillaries.