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Re: FWD>HELP! on monitoring/fro



On Sep 18, 12:06, "Dave Corbitt" wrote:

> 6.  We set White Screen for 6500 degrees Kelvin at 30 FootLamberts.  A circle
> wipe around 4" in diameter (about 10 cm) with white of 100 IRE (NTSC) or 1.0v
> (PAL) inside and black outside is our reference signal for this.  For setting
> Brightness we change the inside of the wipe signal to 30 IRE (NTSC) or 0.24v
> (PAL) and aim for 0.9 FootLamberts.  These figures keep us within Joe Kane's
> guidelines for good full field Pluge display and minimal blooming on
> highlights on anybody's monitor we have tested so far.

This is interesting, Dave, because the Alphie D1 switchers we're using
don't pass the full Pluge signal (the lowest-level chip is invisible),
which makes my monitor black-level check in the morning almost
impossible.  I suppose if my 30 IRE signal is precisely measured, and
the probe is correct for measuring the 0.9 FootLamberts, lowlights
will be close to correct, assuming your math is right.  Of course
that's a bit more involved than simply raising the manual monitor
brightness control until the lowest Pluge transition is just visible,
backing off, and checking if that matches the preset, which was my old
method.  And it doesn't take into account room ambient light-level
differences, though the Kane guidelines probably set a standard for
that as well.

--Rob

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Rob Lingelbach KB6CUN  | 2660 Hollyridge Dr LA CA 90068 213 464 6266 (voice) 
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