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Re: More on monitors



Dave Corbitt wrote about monitor manufacturers....

>(the manufactuers say) Why, I've only heard 2 complaints in the last 3
years >about this.  We are not going to fix it". 

One of the complaints may have been mine.  It never ceases to amaze me how
often I hear "But nobody else seems to have this problem". Yet when you talk
to others, you find you are not alone in your criticism of the product,
pehaps with Brand "A". One other LA facility recently rejected (if I remeber
correctly) seven of eight monitors they received.

>Manufacturer "B" saw the problem a few years ago and went back to the
>factory and came up with a mod to linearize the tracking difference between
>the 3 guns.  The mod didn't actually work very well but at least they
>tried. They have promised to work on it further until they get it right.

I like the attitude of Brand "B" much better and have, and will continue to
test and give them any desired feedback. They may be number two, but maybe
not for long. 

I have been using monitor setup signals from a Snell & Wilcox TPG21
generator, and they are boxes at 20, 50, and 100 IRE.  On Brand "A" I notice
that I can get the 20 and 50 IRE to track within one half percent of each
another, but that the 100 IRE (depending on the monitor) is typically one
half to one and a half percent off (often towards blue).  I typically set up
the blacks at 20 IRE, and then do the whites at 50 IRE until they track the
blacks, and then fudge a little if necessary to bring the 100 IRE witin one
percent or less.  I favor the 50 IRE tracking with the blacks, because this
should allow for more consistent skin tones.  We have to live with peak
whites that tend to  be off about one percent. Some Brand "A" monitors have
this problem worse than others. Soon, I hope to find time to build a series
of test squares between 20 and 100 IRE in 10 IRE increments.  I would think
that setting the monitor up with four points or more points (say 20, 50, 80,
and 100 IRE) might help reduce the error somewhat. Of course another can of
worms is getting 525 and 625 SDI to match. Some monitors are great, and
others pretty rotten.

My concern with manufacturer "A" s monitors is that after about one and a
half years, the blacks are no longer black.  The monitor can be setup
correctly and have the 20 or 30 IRE square read perfectly on the Minolta,
yet the blacks are milky.  The manufacturer can no longer set them up
properly either.  I sent four monitors back recently on ATR due to this
problem, and gotten warranty replacements.  The replacements did not have
this problem (they did have others, but that's a different story).  

I certainly hope that with HDTV coming, the monitor manufacturers will get
their act together.  The only way this is likey to happen, is if enough
facilities complain about current monitor technolgy.  But then again, I must
just be one of those "telecine troublemakers".  Yep, and proud of it!



Craig Nichols
Director of Engineering
Todd-AO Video Services
craign at todd-ao.com
213-465-1231 / 465-2579 fax


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