Xref: utzoo comp.sys.amiga:14823 sci.electronics:2304
Path: utzoo!mnetor!uunet!husc6!mit-eddie!uw-beaver!ubc-vision!fornax!bby-bc!john
From: john@bby-bc.UUCP (john)
Newsgroups: comp.sys.amiga,sci.electronics
Subject: Re: Twisted sony followup
Message-ID: <247@bby-bc.UUCP>
Date: 22 Feb 88 05:26:28 GMT
References: <10419@ut-sally.UUCP>
Organization: Burnaby, British Columbia, Canada
Lines: 49
Summary: my 1302 is like that too

In article <10419@ut-sally.UUCP>, bryan@mothra.cs.utexas.edu (Bryan Bayerdorffer) writes:
> 
> 	Following the advice of David Cantor (thanks, David), I attempted to
> tweak my rebellious CPD1302 into submission via a set of internal
> pincushion controls.  The net result is that the display looks better, but
> still bad.  The left edge of the display is reasonably straight, but at the
> expense of the lower right being more bent.  The screen image is still
.
.
.
I had (still do) the same vertical linearity problem with my 1302 when
I bought it too.  I got mine from an industrial video supply house (they
sell things like studio cameras and monitors as opposed to the usual
consumer items) and hooked it up to a Targa frame buffer at home and
immediately noticed the problem.  I then tried it out on a (much more
expensive) Barco monitor and there was no distortion ("it" referring
to the Targa) so I took it back and complained.  First they claimed it
must be the Targa so I told them about the Barco - their response was
approx. " well you can't expect it to be as good as an $8k monitor".
Fair enough, so I tried the Targa on a cheap tv with ntsc in and it
was still better than the 1302. Back to the supplier - "well tv's have
special v. linearity circuits you can't expect to find in a multiscan
monitor".  Too make a long story short after several trips to these guys
they couldn't improve it and fobbed me off on the Sony wharehouse &
repair center - the Sony guys improved it a bit but it is still easily
noticable when you display a vertical bar.  If it still hadn't been
under the 90 day warranty this "service" would have cost me $150.
Some points:
	1. Number 9 was demoing their boards on a 1302 at Siggraph
	   last year - it had the exact same problem too.

	2. I spent over $1k (US $) to get a monitor that can't even
	   display a straight vertical line.  Sony tv's are great;
	   I will never buy another monitor off them though.

	3. People I talked to say it is the yoke - either you get a
	   good one or you don't but no amount of tweaking will
	   improve the vertical linearity past a certain point.

	4. The sony people explained their guarantee with repsect
	   to image quality.  Linearity is not guaranteed in zone 3.
	   What is zone three?  Draw a diagonal from one corner of
	   the screen to another.  Put the biggest possible circle
	   centered in the middle of the screen. This is zone 1.
	   Now draw the biggest possible circle outside this circle
	   and with it's center on the diagonal. This is zone 2.
	   Zone three is the biggest possible circle, centered on
	   the diagonal and not overlapping zones 1 or 2.  Apparently
	   anything goes outside zones 1 & 2.