TAG DVD32FIR - Manual (Page 19)

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test patterns
aspect ratio
These test patterns output a cross hatch of white lines on a black background, including
several perfect circles. If the geometry of your display device or the output format of the
DVD32FLR aren’t correctly set these circles will look distorted. Make sure your display device
is switched to the correct aspect ratio and you have set the DVD32FLR correctly (see setup-
>change set up->video->aspect ratio)
(1) .
On a 4:3 standard tv the cross hatches 4:3 and 16:9 letterbox should look undistorted.
On a 16:9 display device all 3 test patterns should look correct, assuming the correct zoom
mode is selected (e.g. none, letterbox, anamorphic).
1. A projector usually needs manual switching between the three aspect ratios
convergence
Many display devices form white by generating a mixture of the primary colours red, green
and blue which our eyes add to white. If these colours aren’t hitting exactly the same spot
they won’t form perfect white. This is called imperfect ‘convergence’.
Convergence of some display devices, primarily projectors, can be user adjusted, others will
need a service engineer or aren’t adjustable at all. The quality of the convergence can be
checked using any of the Aspect Ratio test-patterns as they show white lines on a black
background.
If the white lines aren’t white but show the prime colours, shifted against each other, then the
convergence need adjustment.
GRR00868.01-DVD32RFLR UM 5/30/02 12:25 PM Page 36