OSD and Display Evaluation Notes
The on screen display is something that we as users
generally only interact with when something is awry, or when we are first
setting up the display. In those instances the last thing anyone wants is to see is an
amazingly complex menu system which is difficult to move
through and adjust.
With the CML190SXWB, Hitachi use an on screen menu that looks a
bit more descriptive, and flows a bit better then run of the mill OSD's.
It's good to see manufactures invest the time in continually upgrading the
different segments of a display so that the end user has an easier time
figuring things out.
The following controls are available on the menus; Auto adjust, input
select, brightness, contrast, H/V position, sharpness, OSD transparency, clock,
phase, RGB color adjust at user temp, color temp (6500, 7500, 9300, user) zoom,
pan H/V, OSD position H/V, graph/text modes, recall and language select.
As with all LCD displays it is simply much easier to hit the auto adjust
feature and let the display configure itself properly. This only applies to an
Analog connection. When the display is connected to the computer via the DVI
cable the signal is automatically calibrated and the only adjustments remaining
are really only brightness and contrast.
|PCstats TFT Display Evaluation
evaluate the quality of TFT displays with the help of a program called
Nokia Monitor Test. The software application displays a range of colours
and test patterns that can help diagnose just about any visual problems or
defects a TFT display may contain.
It can also be a very useful tool for
properly adjusting a display to the optimal settings. The software
consists of eleven tests which can be run in steps as adjustments are made
to the OSD. As the tests are run we look for the following problems, only
one of which should be inoperable (broken pixel).
Broken Pixels: What we class as a 'broken pixel' can
fall under any one of the following circumstances: Pixel always on (any
colour), pixel always off, pixel unable to display a shade (red, green,
blue, black, white), pixel shown colour gradient.
Pixel Clock: If the number of dot clocks within one
horizontal synch are not properly configured the screen will appear to
drift or vertical stripes may be generated. This should be correctable by
the on screen menu.
Phase: If the phase of the display data and dot clock
are not correctly tuned the screen can flicker, or text be displayed
blurry. For example text may appear dithered, or when looking at a test
pattern of a one-pixel black, one-pixel white checkerboard pattern the
pattern may be distorted. This should be correctable by the on screen
Response Time: We look for any streaking associated
with moving a full page of text up or down quickly. Displays with slower
refresh rates tend to show some degree of image streaking or text
discoloration which can be distracting.
Stand Stability: TFT displays are fragile components and the
stand should offer adequately stable support as well as be easily
We deduct marks for quality control if there are any predominant
broken pixels in a display. While many manufacturers may consider a
few broken pixels acceptable, we believe the high cost of TFT displays
should translate into a clear and unblemished image.
|Display Test System
||ATI Radeon 8500 |
Windows XP |
||Color Temp: 6500 Kelvin|
|LCD Display Test
||Test Notes and Observations|
LCD's inherent design means that test grids are
displayed very true and very square. In this sense, LCD displays are
really good for CAD work as the line render nice and sharp at their
native resolutions. The Hitachi CML190SXWB was tested with a grid
pattern as we do all LCD displays, but to measure grid representation (it
should be composed of true squares) we broke out the ruler and
measured. The grid squares measured 11.5mm x 12.5mm at 1280x1024
which is just about right on.
|Brightness and Contrast:
Good shading on the grey scale, but 1% and 2%
black were hard to discern from one another.
White scales looked really good at an 80% brightness setting.
The white, red, green and blue test screens were very bright and consistent over the entire screen area. There were no visible broken or damaged pixels or uneven areas along
the edges as can sometimes occur on LCD panels.
The grid test patterns in RGB illustrate the worst case situations when different coloured pixels must work closely together,
and since they comprise different parts of a pixel they do not
line up exactly. CRT displays tend to produce better results
under this test as there is more of a blending effect seen by then
All patterns displayed clearly
and defined in both the horizontal and vertical axis. With such a high
contrast ratio the lines are easily distinguishable even though they are separated by
just one pixel lines.
Resolution was excellent at the native 1280x1024 resolution. The
image scaling algorithm was acceptable but not as nice as running it under native
On the one-pixel vertical line test under
an analog connection there was some background noise visible
(just imaging very subtle waves in intensity) as was also the case on
the one-pixel square test screen. The one-pixel horizontal screens
displayed perfectly, as did the two grey tone test screens. When tested
with the DVI digital connection
the test screens were all displayed perfectly, with absolutely
no noise or background waviness.
Other Evaluation Notes:
The stand swivels left and right very nicely and
the tilt mechanism is easy to work with. Overall, this is
a good business class display without the useless inclusion
of tiny underpowered speakers or other "added value" parts which offer no real value to the user.
The build and feel of the unit is very
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