Samsung are well known for
their popular SyncMaster monitor range, with many models being held in high
regard by reviewers and users alike. The model here for review at the moment is
part of another range they are marketing, and is being aimed at colour
enthusiasts and professional graphics work. The XL20 is a 20" (4:3 aspect)
screen featuring an impressive spec and most noteably, an LED backlight
unit. We have also seen the annoucement recently of a 24" and 30" version of
this screen, with the
XL30 expected to be released over the next couple of months.
The LED backlight unit offers an enhanced colour
gamut stretching even beyond that of modern W-CCFL backighting. While CCFL's are
limited to around 92% of the NTSC colour space on modern displays, LED units like this can offer a
gamut covering 114% of the NTSC space. This corresponds to a complete coverage
of the Adobe RGB natural colour space as well. Further to the LED
backlighting used here, the XL20 features an AU Optronics AMVA panel, the first of
this technology we have tested here in fact. Professional colour enhancement is
realized using the Samung designed Color DNA chip (FPGA), enabling high-speed 14-bit
image reproduction, extremely expressive gradiation and exact colours. The 8-bit
input is converted to 10-bit data by the monitor's LUT (Look Up Table), before
being subject to 14-bit data processing to help express further detail. The
screen is packaged with Samsung's Natural Color Expert software and a Samsung
branded X-rite i1 (Eye-One) Display 2 colorimeter. This is the same hardware
device which X-rite provide with
their calibration package and that
LaCie provide with theirs. We already known this to be an excellent high end
hardware calibration tool, and later we will take a look at how effective their
bundled software package is.
The rest of the monitor spec and features as
listed as follows:
16.7M from a palette of 1 billion, 114% NTSC
1600 x 1200
178 / 178
DVI-D and DVI-I
Black bezel and stand
LED backlighting technology, 2x USB hub,
packaged X-rite i1 Display 2 colorimeter and calibration hood. Height,
pivot, tilt and rotate functionality
Above: Front and back views of
the XL20. Click for larger versions
The Samsung XL20
is entirely in a black colour (the bezel is actually a very dark blue, but it
looks practically black), with a fairly thin bezel and discrete OSD
operational buttons. The side view of the screen shows that the display is quite
thick, which is due to the use of an LED backlight unit. One thing unfortunately
missing from the back of the screen design is a cable tie, which is something
Samsung have done on quite a few of their screens as of late (Pebble range for
Above: OSD quick
access to 'color mode', and the 'color tone' menu accessible through the menu
The OSD itself
is fairly easy to use, with all the usual options as well as modes for gamma and
colour tone (a range of cool and warm settings). The buttons also give quick
access to 'color mode' settings, contrast, brightness and source selections.
When using Color Modes other than the 'custom' setting, a light up indication
appears beneath the OSD selection buttons telling you which mode you are using
(e.g "Cal." is displayed when using the calibration preset mode).
height adjustment shown from minimum to maximum
The stand is height adjustable, allowing you to easily position the screen at
a comfortable height for working. The above images show the extreme variations
available in this adjustment, from as low as it will go, to a full height
extension. The fluidity of the mechanism is very good.
The stand also allows you to rotate the screen from landscape
to portait mode. This is also a very smooth and easy to use mechanism and can be
handy for certain work such as reading webpages or writing documents. At least
at this size screen this feature is practical, as I feel it is pretty pointless
on anything much larger in practice.
The screen features a good tilt
function, affording a nice range of movement and the possibility to position the
screen comfortably at any angle.
options shown and small internal fan visible on back. Click for larger images
The back of the screen features a DVI-I and DVI-D interface,
along with the usual power socket you would expect. There is no D-sub (VGA) connection
here, a sign that this is a high end device and is best used with a pure
digital end to end connection. You can use an analogue output if need be, with
the use of a conversion cable and the DVI-I interface, which accepts both
analogue and digital signals. The monitor features a built in power supply, and
there is no need for an external power brick, just the normal kettle lead. Also
evident on the back of the screen if you look closely is a tiny internal fan,
present to help keep the LED backlight unit cool, and dissipate heat. This
Overall the build quality of
the screen was very good, and materials were of a high standard. Because of the
range of ergonomic adjustments, the screen was a little wobbly if you nudge your
desk, but nothing to worry about really.
Colour Quality and
The Samsung XL20 utilises an 8-bit AMVA panel,
capable of producing a true 16.7 million colours from a palette or 1 billion
(14-bit data processing internally).
The colour capabilities of the XL20 are further enhanced by the use of an LED
backlight unit, which offers a colour gamut covering 114% of the NTSC colour
space, considerably more than the usual 72% coverage from standard CCFL
backlighting. Obviously this screen is very much aimed at colour critical work,
and the included detachable hood allows you to appreciate professional
image quality further, with its high style design makes it more than a tool for
eliminating ambient light interference. Plush inner fabric effectively removes
reflection as well.
important thing to consider for most users is how a screen will perform out of
the box and with some basic manual adjustments. Since most users won't have
access to hardware colorimeter tools, it is important to understand how the
screen is going to perform in terms of colour accuracy for the average user. I
restored my graphics card to default settings and set it to its standard
profile. The XL20 was tested at default factory
settings out of the box using the
LaCie Blue Eye Pro and their accompanying software suite.
Default settings of the screen were 70 brightness, 80 contrast. Gamma mode was
set to '0', color mode was set to 'custom' and RGB values were all at a default
Samsung XL20 - Default Settings
Black Point (cd/m2)
Out of the box, the Samsung XL20 performed quite admirably. Firstly, you can
tell by the CIE digram on the left hand side that the gamut of the screen
stretches clearly outside of the sRGB colour space, something which standard
backlighting cannot offer, and only recently exceeded with W-CCFL backlighting
which is used in some modern screens. This is particularly evident in green shades, and in
practice, greens did feel richer and more varied. Gamma was recorded at a value
of 2.0, a little way out from the desired level of 2.2, being the
computer monitors, and the standard for the Windows operating system and the
Internet-standard sRGB colour space. Colour temperature was pretty much spot on,
even at factory settings, being very close (<0.5% difference) to the 6500k
colour temperature of 'daylight' we aim for. Luminance was a little high, as is common for
many screens, and was recorded at 186 cd/m2. With black depth measured at 0.34 cd/m2,
this provided a static contrast ratio of 547:1, pretty close to the specified 600:1
from the manufacturer.
graph on the right shows the DeltaE (dE94) values for colours tested by the LaCie Blue
Eye Pro. As a reminder, the lower these bars down the Y-axis, the better, in
terms of colour accuracy. For reference, LaCie describe the DeltaE readings as:
If DeltaE >3, the color displayed is significantly different from the
theoretical one, meaning that the difference will be perceptible to the
If DeltaE <2, LaCie considers the calibration a success; there remains a
slight difference, but it is barely undetectable.
If DeltaE < 1, the color fidelity is excellent.
The XL20 showed
pretty decent colour accuracy out of the box, with an average dE of only 1.6.
There is a slight difference between the requested and displayed colour, but
overall the colours felt even and rich in practice. This is a good performance
as one would hope from a screen of this price and specification.
Natural Color Expert
branded X-rite i1 Display 2 Device. Click for larger image
The XL20 comes packaged with a
Samsung branded version of the X-rite Eye-One Display 2 device, the same which
X-rite / Gretag provide with their software which we
tested recently, and the same provided with the
LaCie Blue Eye packages.
Coupled with this high end device is Samsung's Natural Color Expert software
suite. Since this is provided with the monitor, I wanted to test its
effectiveness in calibrating the screen, and see what features the software had
Installation of the software
was quick and easy, and on loading the package up, you are presented with the
above screen. This allows you to select between several modes:
Calibration - you can define the target brightness
and black point levels along with the white point (colour temperature) and gamma
levels for the RGB channels.
Emulation - Using the Emulation tab, you can
create a new profile that contains your selected settings, apply an existing
profile, or apply a stereotype of a system profile. Different from a profile
created from the Calibration tab, you can also change the R, G, and B color
gamma. Of course, you cannot use a gamma value beyond the range of gamma values
that can be expressed by your monitor.
Uniformity - Using the Uniformity tab, you
can improve the uniformity of your monitor.
Miscellaneous - Allows you access to load saved
ICC profiles, set a calibraiton reminder frequency, restore defaults and run a
measurement report on the screen.
I first ran the measurement
process which flashed between RGB colours and a white and black shade. This
process took quite a long time, about 5 minutes in total, and certainly longer
than the test and report feature of the LaCie Blue Eye Pro software (~30
seconds). The test feature confirmed that luminance was at 187 cd/m2,
and black depth was 0.33 cd/m2, which was pretty much what we had
found from LaCie's software. A CIE digram was shown, but lacked any reference
triangles for sRGB, NTSC etc. DeltaE values were also not recorded.
Following the calibration
process you are asked to place the colorimeter in the centre of the screen. At
no point are you asked to alter the OSD settings for brightness, contrast or RGB
values. Instead, the process is entirely automated and adjusts the values at a
LUT level and written into the monitor itself, creating an ICC profile as it goes. This process took a long time
though, around 15 minutes total!
At the end you are presented
with a calibrated results screen showing how successful the process was.
Luminance was adjusted pretty well to 121 cd/m2, but black depth
remained at only 0.33 cd/m2, no real improvement from default
settings. This gave a static contrast ratio of 367:1 which was quite a way off
the specified 600:1 from the manufacturer. Gamma was levelled to 2.2 for all
channels, but colour temperature was now a little out, being changed from 6504k
before, to 6447k after calibration. DeltaE was now listed at a value of 0.345,
which presumably is an average value. You are asked if you want to save the
created profile, and you are given the chance to name it as you see fit.
I loaded up LaCie's software to
run a test and report on the calibration results from this process:
Samsung XL20 - Natural Color Expert Calibration Results
Natural Color Expert Calibrated Settings
Black Point (cd/m2)
Testing the results with
LaCie's software showed a positive change in the monitors colour rendering
capabilities and set-up from the default values. Gamma was now corrected from 2.0 to 2.2 and luminance
was now also recorded at a value of 119 cd/m2, not far off the
desired 120 cd/m2. Black depth remained unchanged at 0.33 cd/m2,
giving a usable contrast ratio of only 360:1. This was the only real
disappointment with the screens colour performance, with black depth being quite
poor, especially considering the use of a *VA based panel.
Colour accuracy was improved
with the Natural Color Expert calibration process, with dE now improved on
average from 1.6 to 0.7. LaCie would consider colour fidelity to be excellent
overall. Maximum deltaE was also improved from 3.2 to 2.0, with only a slight
difference now detectable between the requested and displayed colour. Overall,
Samsung's NCE software seems to have done a good job in setting up the screen
more accurately, but the process did feel a little long to be honest. Upon
saving the results, the monitor is entered into the 'calibration' option through
the Color Mode menu, where the results are written into the monitors LUT and not
reliant on whether NCE is running or not. Switching back to the 'custom'
Color Mode allowed you to quickly see what the screen looked like before the NCE
I ran through LaCie's software
package again to see if further correction was possible:
Samsung XL20 - LaCie Calibrated Results
LaCie Calibrated Settings
Black Point (cd/m2)
I restored the screen to
default values and discarded the profile created during the NCE process. During the calibration process with LaCie's software suite,
the brightness setting was altered to 45, contrast remained at 80 and the RGB
values were changed to 48, 43 and 50 respectively. This calibration process
does allow you to alter the OSD settings to help achieve the most accurate
results possible, something which NCE did not offer. However, it should be noted that this adjustment
only forms part of our calibration process, and the majority of the changes
occur at a LUT level, as an automatic process altered by our colorimeter.
Gamma was corrected nicely to 2.2 and luminance was also corrected to the
desired 120 cd/m2. With black depth now recorded at a slightly
improved 0.27 cd/m2, contrast ratio was 444:1, still a little way off the
specified 600:1 from the manufacturer.
Colour accuracy was improved quite considerably, with an
average dE of only 0.4 (colour fidelity is excellent) and a maximum of only
0.8. Overall I was pleased with the results here, and the AMVA panel showed
some very good colour rendering capabilities. LaCie's software offers a little
extra in the way of calibration accuracy, and obvious offers the test and
report features we have shown here, which are very useful to help quantify
your results. I tested the screen with colour gradients which showed no issues
with colour banding at all.
One problem the enhanced-gamut
monitors are bringing about is how to make them correctly reproduce images
prepared for older, sRGB, monitors. Widespread graphics file formats encode
colour not with some absolute values (e.g. with CIE diagram coordinates), but
with some relative units. It means such files are going to be displayed
differently on monitors with different colour gamuts. So, a picture prepared for
an ordinary sRGB monitor is going to have extremely saturated colors on the
screen of monitors such as the XL20. It can be said that its colour gamut is
forcibly stretched out from its native sRGB (72% NTSC) to the XL20ís colour
gamut (114% NTSC).
There are two ways to solve
this problem. First, an ICC profile is created after calibration and each
program that has colour management options can learn the monitorís colour gamut
from it and correct images appropriately. Second, the XL20 monitor can emulate
any colour gamut smaller than the monitorís own gamut. This is offered by the
'Color Mode' option, accessible through the 'mode' OSD selection button. When
you press that button, a menu with five modes opens up:
Custom: the user has access to all of the
monitorís settings and the colour gamut is not limited at all
sRGB: the monitor emulates the sRGB colour gamut
and the user-defined settings are blocked
AdobeRGB: the monitor emulates the AdobeRGB
gamut and the user-defined settings are blocked
Emulation: the emulation set up in the
corresponding mode of the Natural Color Expert utility is enabled. The monitor
offers full-featured hardware calibration with the results being written into
the monitorís rather than the graphics cardís LUT and this mode will work
irrespectively of the software you use
Calibration: the monitorís calibration results
are enabled. Like with the emulation, the results are written into the
monitorís LUT and do not depend on whether Natural Color Expert
is running or not
By switching to the sRGB Color
Mode setting you could immediately tell that the colour range was reduced, and
after using the XL20 for a long period of time, it felt strange reverting back
to this level of colour. Testing the screen with the LaCie probe again allowed
me to see that (as shown above), the monitors gamut was now simulating the sRGB
colour space, and was considerably reduced from the gamut tested before. It is a
nice feature to offer this emulation of smaller colour spaces, and this could
well be useful to colour enthusiast work.
Viewing angles of the Samsung
XL20 were very good, with the image being clearly visible even from extreme
angles. The AMVA panel technology shows none of the major contrast shift
vertically that you can see from TN Film based models, and therefore does not
show the characteristic blackening of the image when you look from below. There
was a slight contrast shift detectable as you move away from a central field of
view, and some slight pink tinting when you get further away. This was only very
slight though, and quite hard to detect in normal use. S-IPS is often used in
other colour enthusiast orientated screens, and can offer slightly wider viewing
angles, and does not show the slight constrast shift when you move from a
central view, which is inherant to VA panel technologies.
In our usual testing process I viewed an all black
screen in a darkened room, which allowed me to test the uniformity of the panel
and to examine whether any backlight bleed was evident. There was no detectable
leakage from the backlighting, and the uniformity remained very consistent. The
top half was perhaps ever so slightly brighter than the bottom, but hard to capture with
The Natural Color Expert
software offers another handy feature here as well, that being an option to help
improve screen uniformity. You can choose whether to use a 9 point or 15 point
reference grid, and are asked to place the colorimeter over each part of this grid in turn.
Brightness is measured by the device, and at the end, the brightness uniformity
across the screen as a whole is automatically adjusted. That is the theory at
least. It was difficult to detect much in the way of change, but then uniformity
was pretty good from the outset anyway.
Office and Windows Use
I found the Samsung XL20 to be pretty good in
Windows and office use, with it's tight pixel pitch of 0.255mm being well suited
to viewing text. The DVI interface obviously offered a nice end to end digital
connection, and resulted in clear text and a very good picture quality. I found
it a little hard to get used to using a 4:3 aspect screen againn however, and
the lack of a WS format meant it was not easy to do any side by side working.
The preset colour modes did not offer any 'text' option, something which is
often quite useful for office work when you are working in low light conditions,
and want to reduce the monitor brightness somewhat. All in all, I personally
prefer a WS format screen for normal work, but I can't really hold that against
the XL20 as it isn't marketed in this way! The rotate adjustment might prove
handy for some users, and is at least functional at this screen size.
Responsiveness and Gaming
The Samsung XL20 was tested using the chase
test in PixPerAn, a good bit of software for trying to quantify differences in
real terms responsiveness between monitors. As a reminder, a series of pictures
are taken on the highest shutter speed and compared. The images above show the
best case example on the left hand side, and the worst case example on the right
hand side. This should only be used as a rough guide to comparative
responsiveness but is handy as a way of keeping a constant test of each screen.
As you can see from the above
images, the 8ms G2G rated AU Optronics AMVA panel performed very well here. In
the best case image on the left, it was very comparable with the 8ms G2G rated
S-MVA (from CMO) panel from the Viewsonic VX2435WM, showing that the 8ms G2G generation of
VA panels are all quite comparable. The performance remained a little behind the
very well regarded NEC 20WGX2, which features a 6ms G2G AS-IPS panel from
LG.Philips. I was impressed by the responsiveness of the XL20 in these tests,
something which you perhaps wouldn't expect from a high end professional screen
such as this. If you are a graphics or photo worker, and need the high end
colour capabilities from your screen, but also want to do a bit of gaming, this
may well be a good choice.
This response time is made
possible through the application of RTC (Response Time Compensation)
technologies, which can sometimes lead to some overshoot and artefacts. In this
case, there was no obvious sign of any such issues, and the RTC impulse seemed
to be well controlled. Motion blur was detectable in games if you knew what to
look for, but there was no sign of ghosting or trailing of the images in
practice. To elminate motion blur you would need to consider screens with
additional measures for handling this, such as MPA, BFI or 120Hz technology.
As usual I tested the
screen in clone mode with a CRT to determine the level of input lag. This is
something which can put off some gamers and is a delay between graphics card and
monitor output. By hooking up a CRT you can show that the LCD lags behind
somewhat, which can affect users in some situations where they rely on the
screen image being as fast as their inputs (e.g. fast FPS shooting games).
Often, input lag is very low and probably wouldn't represent too much of a
problem in real terms.
The above graph shows the
average input lag across several screens tested at TFT Central,
and also average input lag as recorded from other sources on some
popular and well established models. As you can see, the input lag of the
XL20 was quite high, with an average of 34.4ms delay between the images. Maximum
input lag was also 41ms. Obviously this screen isn't really aimed at the gaming
market, but an input lag of this degree could prove off-putting to some buyers.
In other uses, obviously there is no problem at all.
Movies and Video
When considering whether a display is well suited
for movies, you need to consider a few things:
support over a digital interface is vital for viewing HDCP encrypted content.
Unfortunately the XL20 does not offer this support over it's DVI interfaces,
which could cause a problem in the future.
interfaces are becoming more common on modern screens, but the XL20 features
only a DVI-I and DVI-D interface. Connection of external devices could be
tricky, and it was also a pity not to see a dedicated D-sub interface, which is often used
for connecting games consoles.
angles must be wide if you intend to have more than one person watching the
video. Thankfully the AMVA technology is strong in this regard and perfectly
well suited to viewing the screen from a variety of angles, or with several
depth must be good to allow darker scenes to be rendered correctly, and for
detail to be distinguishable. The 0.33 cd/m2 black depth is quite
average here, and not as good as we have seen from some PVA, or even TN Film
based panels. In practice, it didn't prove too much of an issue anyway.
noise must be kept to a minimum, otherwise artefacts and twinkling in large
colour masses can be noticeable. MVA panel technologies are considered to be
good in this regard, and the AMVA panel in the XL20 performed well. There was no
real issue with noise when sitting at a sensible viewing distance.
format monitors are obviously much more suited to viewing movies than a 4:3 or 5:4
aspect screen. The XL20 is of course 4:3 aspect, with its 1600 x 1200
resolution, and so this results in large black borders being used when watching
DVD's or any other WS content. The Samsung XL20 can show movies and video quite
well really, but if this is going to be a primary use for you from your screen
I'd suggest a WS format display would be far more suitable. The forthcoming
Samsung XL24 and XL30 are both WS aspect and may well be more suited.
colour gamut helped make colours look vivid and bright in movie playback, and
you could compare this improvement quite easily by switching to the limited sRGB
mode. If colours appear saturated then you also have the option to switching to
a different emulated colour space.
The Samsung XL20 is an impressive screen. There's
no doubting that it's performance and features are high end, and it is capable
of offering not only some excellent performance in its target area, colour work,
but also in other areas as well. I was impressed by the colour rending
capabilities of the LED backlight unit here, and the inclusion of a decent
hardware colorimeter was a nice touch. Obviously a screen like this comes at a
cost, and with current retail prices of around £790 GBP / $1700 USD, it is
clearly a more expensive option than some other screens in the market. However,
for colour critcal work, it is a good option, and pleasingly, it wasn't let down
in other areas such as responsiveness. The only thing which was a little
disappointing was the black depth of the screen, and the contrast ratio was
recorded at lower than even the 600:1 quoted spec.
If you can afford the high price tag, or are
looking for a colour enthusiast screen for work, the XL20 is a good option. It
will be interesting to see how the XL24 and XL30 compare when they hit the
market, although the price point is surely going to be even higher.
Excellent colour accuracy and extra wide
High price tag puts it out of
reach of most average users
Good responsiveness, despite
being a colour enthusiast orientated screen
Disappointing black depth and
low contrast ratio
Good range of ergonomic
adjustments and useful packaged colorimeter
Natural Color Expert software
is very slow!