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Philips LDH0462/00 Information Sheet page 2


Iris Adjustment (Auto-iris lenses)
Auto-iris lenses are usually pre-adjusted for an acceptable image under average conditions.
Re- adjustment may be necessary to obtain optimum picture quality.
Aim the camera at a grey-scale test chart.
Set the 'ALC' variable resistor on the lens to its Average position.
Connect an oscilloscope to the iris control output (3-pin DIN pin 2). Adjust the setting
of the 'Level' variable resistor until the maximum signal from the scene (peak white)
reads 1 volt.
Note: If you have no suitable test chart, aim the camera at the scene you want monitored and
proceed as described above.
When the image on the monitor shows an extremely high or low contrast, follow these steps:
HIGH CONTRAST: Slowly turn the 'ALC' adjustment to Peak and the 'Level' adjustment to
LOW CONTRAST: Slowly turn the 'ALC' adjustment to Average and the 'Level' adjustment to
Also consult the documentation that came with your lens.
Passive auto-iris lenses need no adjustment.



This manual is also suitable for:

Vcm 6459/00t