If the default exposure settings do not produce acceptable results, you can adjust the
SharpZ3 ALPR camera exposure settings.
Procedure
-
Place a stationary license plate as close to the
camera as possible while still being within range for the camera to capture plate
reads.
-
Log on to the Sharp
Portal.
-
From the Configuration menu,
click .
-
From the Cameras menu, click the
ALPR camera you want to calibrate.
-
From the Exposure menu, click Range
(outdoor).
Gain and
Exposure time
settings are displayed.
NOTE: The ranges for the Exposure time
and Gain settings must be large enough to allow good
quality images in all lighting conditions, but you should reduce the range as much
as possible. If the range is too large, it increases the risk of over-exposure or
under-exposure. It is normal that the SharpZ3 constantly
varies the exposure of the ALPR camera in order to get a correct exposure of a
plate.
Tip: If you want to test using specific exposure settings
rather than a range, use the Fixed (indoor) configuration
from the Exposure menu. However, the setting should be set
back to Range (outdoor) for normal operation so that the
camera can adapt its exposure to varying lighting conditions.
-
With the plate close to the camera, set the Gain value to
the minimum default value and adjust the Exposure time until
you are satisfied with the plate image.
-
With the plate further from the camera, check to see that the plate is not too
dark. If it is, increase the Exposure time.
-
(Optional) If you reach the maximum possible Exposure time
and you are still not satisfied with your plate image, increase the
Gain.
-
When you are satisfied with the appearance of the plate images in the video feed
window, click Save.
The system displays the message Configuration saved
successfully.
After you finish
Modifying the exposure settings can greatly impact ALPR
performance. Test the system after modifying these settings.