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Edge blend problem


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We are getting a dark streak at the edge blend and even a problem with a hard edge. Any tips??? URGENT, since we have a show going up next week.


Watchout v. 5.1

Projectors: Christie DHD 800


We've tried everything in preferences.




Without specifying the display signal connection type, it is hard to narrow it down.


A dark streak in the edge blend is a common issue when driving the projector with an analog signal (VGA).

One reason it occurs is when the signal is not accurately aligned to the projectors chip(s)

due to the interpolation ambiguities of the analog signal.

i.e. if the signal overshoots or undershoots the chip, a dark band in blends will result.

Aligning the display raster to the chip is an extra step needed with analog driven projection systems.

This does not usually occur with digital driven systems.


This was actually addressed in older user guides, but it was dropped in recent revisions.

i.e. current User Guide makes no mention of analog connections, just assumes the world has gone digital :D


Another possible cause for banding – particularly near the edges of images –

is long or faulty VGA cables. Try connecting the display directly to the

computer using a short VGA cable to see if this has any effect. ...

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