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FOCUS
Use the Focus page to select either Auto back focus or Manual back focus, adjust the available settings, or reset the back focus to factory
defaults.
NOTE: It is recommended to set focus to Manual when using analytics. If focus is set to Auto, significant background changes will occur when
the camera auto-adjusts to different points within a scene resulting in frequently changing image sharpness. This may cause problems with
scene recognition, which will suspend analytics operation or cause false alarms.
Auto Focus
Auto focus automatically back focuses the camera on the subject in the center of the scene. The camera will refocus when changes in the scene
are detected.
Figure 24. Auto Focus Page
The available auto focus settings are as follows:
Periodic Refocus: The camera is programmed to run a quick auto focus sequence every three hours to maintain optimal focus. This periodic
focus sequence adjusts the center focal point of the scene to compensate for small focus changes caused by environmental temperature, camera
vibration, or other conditions. The default setting for Periodic Refocus is On. Select Off to turn off Periodic Refocus.
Day/Night Switch Refocus: Available only with day/night cameras. When enabled (On) this setting refocuses the camera when the camera
changes from day mode (color) to night mode (black-white) or vise versa. For example, if the camera changes from day mode to night mode, the
imager automatically adjusts the back focus for the change in light.
The default setting for the Day/Night Switch Refocus is Off. Select On if the camera’s focal length is greater than ~25 mm, or the night scene
uses mostly IR lighting. The best method to determine if the day/night refocus should be enabled is to test the camera with the daytime light
conditions, and then test it again with the nighttime light conditions.
Full Range Auto-Focus: The camera starts a full-range search to find the best focal point for the scene.
Quick Auto-Focus: The camera searches for the best focal point in a limited range.
Factory Defaults: The camera resets the auto focus to the factory default setting.