Barco SP4K-B, Installation Manual

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117 R5912128 /03 SP4K-B
Convergence test pattern
Image 10–8
The test pattern illustrated above is specifically designed for convergence purposes. The test pattern has
three blue arrows numbered from 1 to 3 and three green arrows numbered from 4 to 6. These numbers and
colors correspond to those of the control knobs. Turning the control knob clockwise corresponds to the
direction indicated on the screen.
Basic instructions
Keep into account the following:
• BLUE and GREEN DMD’s are to be adjusted with reference to the RED DMD.
• Each adjustment allows for 20 pixels maximum displacement to either side of the nominal RED position.
• Rotation is limited to approxi/- 10 pixels on the left screen flank and +/- 10 pixels on the right
screen flank.
• One turn of a control knob relates to an approximately 10 pixels displacement on the screen.
• Before starting to adjust the convergence, let the projector warm up for at least 1 hour, while projecting the
convergence test pattern and while using the correct brightness level.
Adjustment Range
Avoid slipping of the torque limiter clutch by limiting the amount/number of adjustment(s) made. Typically the
convergence adjustments serve to correct a convergence fault of a few pixels at the most. Any convergence
fault beyond this is considered grossly abnormal and likely indicates abuse or rough handling..
CAUTION: The system does have an end of travel in either direction, but using excessive force may
cause damage. Please handle gently.
Troubleshooting 'dead zone' of control knob
In rare cases it can happen that a control knob is loose in the perfect convergence position. This means that
the nominal DMD position falls within a
dead zone , where the mechanism changes from a pushing to a pulling
function. This dead zone is due to inherent tolerances within the mechanism. If it so happens that the nominal
position of an adjustment falls within this dead zone, it is preferable to continue screwing through the dead
zone for another 2 turns. Then return to the required nominal position. The dead zone should now be
displaced away from the required end position. The DMD is now securely held in the nominal position.
Convergence