Online LCD Monitor Panel Type Evaluator
Our LCD Monitor Panel Type Evaluator is a very quick and simple
way to test what type of LCD monitor you are looking at
right now, how good it would be for photography and video
processing or simply help you to choose the right "one" from an
endless
row of monitors in a store.
There are few major types of LCD monitors each using
different technology and each targeting different users
needs and budget. Unfortunately the LCD
panel type info is hidden somewhere in the
specifications (if at all) and the vivid image slideshow
used in the stores are hardly any reliable way to
evaluate a monitor.
Without going too much into the details (you can read
wikipedia on that topic) a LCD monitor
may be usually one of these:
- TN LCD monitor - those are the
typical budget monitors found in all the big box
stores. Also nearly all laptop monitors are this
category. They have large color shift mostly from
top to bottom angles and are not good for
image editing
as they show false colors just by moving your head.
However they are non expensive and have fast
response so they become quite popular for everyday
tasks.
The limited horizontal
viewing angle makes TN monitors
unusable for using in a portrait
position, even if some manufacturers did put a pivot on
few of them (a marketing gimmick).
TN monitors are all also 6 bit instead of 8 bit so
they can display true colors using dithering which
unfortunately could show on a smooth photographic
gradients.
- S-PVA LCD are little more
expensive monitors that usually come with a contrast
ratio sticker bearing some bigger number like
3000:1. They don't have much of a color shift
problem unlike the TN.
However the usual problem for image editing is that
looking right in the center they crush the blacks
(not-so-blacks will merge with the total blacks into
one tone) while if looking from slight angle the
contrast will be more real. This leads to the false
impression that your image is too dark in the bottom
end and users tend to adjust
their alpha parameter in levels higher on nearly all their
images (while it was probably fine). A
calibration will help, but then moving your head
into an angle will make the image look washed out and
too bright and that may be confusing even more.
If you understand the black crush they could be ok
for image editing. They can also be
used in portrait mode because the viewing angles
from top and bottom are equally good than from left
and right.
Because they are only little more expensive than TN they are
a good bang for buck.
- S-IPS LCD, most photographers
favorite monitors. They have very minimal color or
contrast shift from any angle and so they can be
also reliably calibrated and show true image. You
can see a good S-IPS monitors in big box stores
often only in the Apple section as they are mounted
in desktop iMacs and the Apple Cinema Displays. For
Windows PC you will probably have to order them or
buy them in more business oriented stores (few
occasional exceptions in big box stores). Prepare to
pay at least 2-3 x more than for same size of TN
monitors. A good S-IPS monitors will be a reliable
tool for any photographer and almost necessity for
people who work with prints. The older S-ISP were
usually slower in refresh rate (not good for games)
but the newer seems to be as good as everything
else.
So how to test which type monitor you are looking at
right now?
Use the following Pattern test
page. You will need to resize the page on full screen
and also if possible hide the menu bar and tool bar
(usually pressing F11). Make sure the browser zoom is
100% (It is very important, so iPad owners don't bother with this - you have
S-IPS monitor anyway)
Click
here to go to the LCD Panel Pattern test page.
The next test is for Banding and Colors. You don't need
to use it in a full screen.
Click
here to go to the Banding and Color test page.
How to interpret what you saw in
the
Panel test pattern
This will give you a very firm idea what is your monitor
LCD Panel Type.
Please note, even between the same types there are always
better and worse quality. Well calibrated monitor will
also display more gray than green or purple color on this
test pattern.
TN LCD Panel
:
S-PVA LCD Panel:
-
When looking from front you
will see pale green color on sides with some
purple shade towards the middle. Depending on
the calibration the color may look more grayish
or purple.
-
When looking from bottom or top the green color will
intensify and become more solid.
Looking from all directions the color will be
the same - green(ish)
-
When looking from front
at S-PVA panel, (depending on your calibration
and room color) the color may be in the center
more gray (good) or purple-gray (not as good)
than green but the color will still slightly
graduate toward green sides.
However when viewed from angle in any direction the
color of S-PVA will become green and solid.
S-IPS LCD Panels (also H-IPS, e-IPS):
-
The monitor should look uniformly gray across
the whole screen.
e-IPS could have center slightly
brighter than sides but it still should not have much
of any tint.
-
Looking from any angle and any side the color
should remain nearly gray but when looking from
extreme wide angle it may get a dark-blue tint.
The
IPS monitor should show very little hue on the
test pattern when looked from a step back. Also
if you look from any direction and under most
angles it should remain gray.
It may show a little dark blue tint towards
opposite edge when viewed from extreme angle.
(This is normal).
A quality monitor will not show any tint of any
hue, lesser quality may show a little pink
and/or purple tint around edges and corners.
Banding and Color test pattern
This pattern show smooth gradient in grayscale and a
special combination of three gradient colors.
Banding happens when a LCD panel is not able to
correctly reproduce the true colors and smooth gradients
will show as a more or less noticeable bands. A good LCD
panel will display perfectly smooth transition.
The image below is an exaggerated simulation of what
bands may look like. You will hopeffuly not see it this way on any
LCD monitor as this is really overdone for clarity
purposes.
Normally you may see this on lesser S-PVA and most of TN monitors.
However the new monitors use various dithering and frame rate control
processes in order to minimize the banding. (It is a whole science dedicated
to this issue)
Even a very good TN monitor will always fail the first Panel test due to
color shift but may have only marginal or no banding issue due to advanced
dithering mechanism.
On the other side a less expensive S-PVA may show stronger banding due to
using only 6 bit LCD matrix instead of 8 bit (a professional panels would go
even higher) and lacks adequate dithering.
A good S-IPS (including e-IPS) should show no color banding.
Colors: the Pleasant and the Ugly - the color
gradients on the Banding test are specially selected to test color
saturation issues. The colors are not in-your-face cheerful primary colors
like in many other monitor tests (the primary colors usually look good
everywhere) but are selected to emphasize the issue. The
saturation on the left side of the gradient is actually at 100%.
Because of the full saturation the color on the left side should look vivid
and pleasant and not pale or greyish. Also the vivid look must be true along
the gradient continuing right and not simply fade into a pale tint.
It may not be that easy to see this issue if you are looking at only a
single monitor but when comparing few panels this will become very apparent.
On a good monitor the colors could be still called cheerful or clean but on
a lesser monitor those colors will get the immediate benefit of being
labeled "ugly" or dirty colors and no amount of fiddling with the
monitor setting will cure this.
A picture from any recent digital cameras will simply pop when viewed on a
monitor that passes this test because the images from modern cameras are
indeed well saturated. (it is a selling point)
On lesser monitors the images will look less saturated and less "happy" than
they really are even after hours of careful calibration.
Both TN and S-PVA LCD types will have models on both side of the fence. The
S-ISP monitors should normally be more in the scale of ok-to-great and they
often respond well to cranking up the brightness a notch.
So how did your monitor rate?
The least desirable monitors for photography would be the
TN. This is the one that shifted colors from green to
purple as you move your head in horizontal direction
(less in vertical). Such monitor would be hard to use
for serious photography work as you will constantly see wrong
color tint depending on
your head position. All laptops are usually in this
category as well as most less expensive monitors in big
box stores.
You can minimize the color gradient by
tilting the monitor so you are looking at it slightly
from the top. It is however impossible to correctly
calibrate such monitor because of its natural flaw, it
usually works better if you simply set what looks good
to you and save some money for a better monitor.
Also TN monitors may suffer from various dithering and
banding issues because vast majority of them are only 6
bit (each pixel can clearly differentiate only 64 tones
instead of 256 for 8 bit monitors). It is not uncommon
to see people with TN monitors trying to smooth out a
perfectly fine gradient. The banding is a
serious issue for illustrators or 3D artists because the
smooth gradients are their bread and butter.
While not good for image processing the TN monitors are
fine for all other purposes, such as office application
and the fast response are also popular with gamers.
Next will be S-PVA monitors that could be recognized by
the fact that when viewed from the front the pale color
of the Panel Test (or
gray shade if it is a calibrated monitor) is not that
uniform and it goes toward green on sides which can be described as
a slight vignette effect. Depending on the monitor
this vignette may be shifted towards one or the other
side.(Even two same models could be different).
However when you look at an angle in any direction the
test patter will become solid green. You can adjust the monitor RGB colors so it has as
little of the green tint as possible when looking from
front (but you won't be able to change the color
vignette). Less expensive PVA monitor may not be fully 8
bit and will use similar methods of dithering to display
true colors. This may be noticeable and/or shows as
banding on smooth gradients.
The best monitor for working with images will show the
Panel Test pattern as a neutral gray (look from a step back,
don't glue your face to monitor) and still remain
mostly gray
when looking from any angle and any direction. A bit
less perfect would
be a monitor that shows gray when looking straight on,
but then shows some hue in the very edges and corners (green
and purple) when looking from angles. Also the
cheaper variants have less expensive backlight which
will make the center more bright than edges.
The less expensive variant of S-IPS is e-IPS
however it is also newer technology with faster response
time and can be priced close to the S-PVA monitors. The most
expensive are the H-IPS and P-IPS variants that are used
only for professional grade monitors. All of them are the
most desirable technology for photography but differ in
price. A good example of excellent S-IPS monitor could
be seen on Apple desktop iMacs and Apple Cinema
Displays.
Calibration
Some people feel that any LCD monitor will benefit from
hardware calibration and custom color profiles. This
isn't necessary so. A lesser quality LCD monitor cannot
be properly calibrated with hardware calibration device
especially if you try to change its white point to the
standard 6500K. After doing so it will simply look way
off resulting in many hours of frustration until one day
you will finally reset it back to its native state that
is derived from whatever random backlight the good
people who made it put there.
On the other hand calibrating a good quality monitor is
not only a great idea it is also a painless process
resulting in great looking images on the monitor that
are also technically correct.
Please note this text is written with regard for photo
and video editing. For normal office environment most of
this doesn't apply.
It is work in progress.
If you have comments or see omissions or errors,
please contact us.
(c) Mediachance.com 2010