🚀 go-pugleaf

I recently purchased an Iiyama Vision Master Pro 17E monitor following
the rave reviews that it has received in the press and recommendations
from various other sources.

Although initially impressed by the brightness and clarity of the
Diamondtron screen - probably what gave rise to the recommendations -
when I started to use the monitor in earnest I was appalled at the image
distortion.  I first noticed this distortion when I drew a circle on the
screen and found it distorted into an ellipse.  I thought this might
have been that the width and height of the screen that was out of
adjustment, so I dragged out a ruler and measured it.  It was pretty
close to the correct 4:3 aspect ratio, but I set it up exactly using the
adjustments.  Even after doing this, the circle was still distorted into
an ellipse.

Further investigation showed that the distortion depended on the size of
the circle and the position on the screen.  It was in fact due to a
horizontal non-linearity present in the monitor!  Since this was not
present on my old cheapo monitor, I was quite surprised to see it on
such a high quality monitor.  Roughly speaking, if I use a drawing
package to put a 10mm square in the middle of the screen, it appears as
a rectangle which is only 9.5mm wide.  If I then move the rectangle to
the edge of the screen it appears 11.5mm wide!  So from the centre to
the edge, the horizontal scaling changes by 20% - quite abysmal in my
view and totally useless for precision work.

I called Iiyama, and they told me how to adjust the default settings for
the monitor, but unfortunately horizontal linearity is not adjustable -
although vertical linearity is (so you can make the screen just as bad
in the vertical axis as it is in the horizontal!).  Iiyama agreed that
this was a fault, and exchanged the monitor for me today.
Unfortunately, the distortion is just as bad in this monitor as it was
in the original one - and to make matters worse, this one also suffers
from horrific vertical convergence errors in the top left hand corner of
the display - the red and blue beams are over 1mm apart vertically in
this corner but fine in the other parts of the screen.

To get a distortion free screen with both of these monitors, I must
reduce the scale of the image to less than 10 x 7.5in - about the size
of a 15in display screen costing less than half the price!

Is this typical of IDEK/Iiyama models?  Do they all have lousy
distortion?  If anyone has this monitor (or a similar Diamond Trinitron
screen based unit) can they run the simple test outlined above and let
me know if their unit is the same, better or worse, and if so what make
it is.

A more critical test is to fill the screen with a series of vertical
lines, each one pixel wide and one pixel apart.  This will cause a
severe moire pattern will then occur due to the interference with the
lines and the 'shadow-mask' (I know these monitors dont have real
shadowmasks, but you know what I mean).  If the linearity is perfect, or
nearly so, the broad bands of the interference pattern will be evenly
spaced across the screen - as it was on my old 14inch model.  With the
super expensive Iiyama Vision Master Pro 17, these bands range from 1cm
wide in the middle to less than 1mm wide half way to the edge of the
screen.  This is a very critical test I admit, but since I have a little
14in display that manages to get it nearly perfect I think that it aout
to be possible to achieve in an expensive 17in so called Pro monitor
like the Iiyama!

Has anyone experience of this or other problems with Iiyama?  Is it a
design fault?  Does anyone know of a solution to the problem - other
than taking it back to the salesman and requesting a refund since it
clearly is not fit for the purpose for which it was intended?
-- 
Kennedy
Yes, Socrates himself is particularly missed;
A lovely little thinker, but a bugger when he's pissed.
Python Philosophers