Introduction
Over the last year or so there has been a growing
interest in low-cost monitors being manufactured in Korea and distributed
Worldwide, primarily by sellers on eBay. These screens have captured the
interest of buyers since they are generally high resolution models (27 and 30"),
using quality IPS panels as used in popular models from the likes of Dell and
Apple, and importantly, are available at very low costs. We talked about these
Korean screens a little, back in
March 2012 but have not really had chance to look at them in any more detail
since. While they have been discussed a lot online and snapped up by many buyers
looking for a bargain, there have always been big question marks around their
quality and warranty. Shipping these models internationally via eBay has been a
little worrying for many people, and with doubts around the after-sales support
and returns policy, many people have just been put off.
Some local alternatives have emerged since,
helping to offer people other low cost screens but with the safety net of a
local
distributor and support/warranty structure. In the UK, models like the
DGM IPS-2701WPH have emerged to offer a low cost alternative to the
mainstream offerings from Dell, HP, Apple, NEC and the likes. While these have
no doubt been a lower end display choice, with a more basic set of features and
specs, they have still interested many buyers looking for a bargain. Despite the
availability of these local alternatives, the Korean models have remained
popular.
Now UK-based IT supplier
www.pcbuyit.co.uk have
started to supply some of the Korean models themselves, backed by a proper
warranty and support service as well. So far, models from Achieva Shimian are
starting to emerge through PCBuyIT and we have the 30" QH300-IPSMS with us for
review at the moment. We will feature reviews of other Korean models as they
become available as well. In regards to the warranty, PCBuyIT are including a 3
year UK only collect and return warranty. Full details of the support offered
with the QH300 is
available here for reference.
Specifications and Features
The following table gives detailed information
about the specs of the screen:
Monitor
Specifications |
Size |
30"WS (76.2 cm) |
Panel Coating |
Heavy Anti-glare (matte) |
Aspect Ratio |
16:10 |
Interfaces |
1x Dual-link DVI (HDCP), 1x HDMI, 1x D-sub |
Resolution |
2560 x 1600 |
Pixel Pitch |
0.2505 mm |
Design
colour |
Dark silver colour brushed aluminium
appearance bezel and casing. Black stand and base |
Response Time |
7ms G2G |
Ergonomics |
Tilt,
swivel, 125mm height, rotate |
Static Contrast Ratio |
1000:1 |
Dynamic Contrast Ratio |
n/a |
VESA Compatible |
Yes 100mm |
Brightness |
370 |
Accessories |
DL-DVI cable, Power cord and brick, audio cable |
Viewing Angles |
178 / 178 |
Panel Technology |
H-IPS |
Weight |
Not
listed |
Backlight Technology |
WCG-CCFL |
Physical Dimensions |
(WxHxD with stand)
685 x 516 x 208 mm |
Colour Depth |
1.07 billion (10-bit) |
Refresh Rate |
60Hz |
Special
Features |
Audio out connection |
Colour Gamut |
Wide Gamut
102% NTSC, 98.2% Adobe RGB, 100% sRGB coverage |
The Achieva Shimian QH300-IPSMS offers a
reasonable set of connectivity options. There are HDMI, Dual-link DVI-D and
D-sub (VGA) provided for video interfaces. The DVI connection should be used
where possible, but we did find that the VGA connection even supported the full native 2560 x 1600 resolution
which was unusual. It's nice to see HDMI provided for
users who want to connect other devices, particularly external Blu-ray and DVD
players. The digital interfaces are HDCP certified for encrypted content as
well. There is also an audio out connection for connecting headphones / external
speakers if you wish to take the sound from the HDMI input. There are no
integrated stereo speakers on this model so the "audio in" connection can be
ignored.
The screen comes packaged with a dual-link DVI and
audio cables which is useful although there is no
VGA or HDMI cable provided with the screen unfortunately,
presumably due to cost saving measures. The screen has an external power supply
which is provided as well. There are no further features such as USB ports, card
readers of light sensors on this model.
Below is a summary of the features and connections
of the screen:
Feature |
Yes / No |
Feature |
Yes / No |
Tilt adjust |
|
DVI |
|
Height adjust |
|
HDMI |
|
Swivel adjust |
|
D-sub |
|
Rotate adjust |
|
DisplayPort |
|
VESA compliant |
|
Component |
|
USB Ports |
|
Composite |
|
Card Reader |
|
Audio connection |
|
Ambient Light Sensor |
|
HDCP Support |
|
Touch Screen |
|
MHL Support |
|
Hardware calibration |
|
Integrated Speakers |
|
Uniformity correction |
|
PiP / PbP |
|
Design and Ergonomics
Above: front views of the screen. Click for larger versions
The screen comes in a matte dark silver
design with a plastic bezel designed to look like brushed aluminium. The
bezel is thin and sleek and measures only 20mm along all sides. The design
is sturdy and seems to be of a good build quality, although perhaps a
little industrial. There is a single "Shimian" logo in the middle of the
lower bezel but no other writing or labels on the screen at all. There is
a very small power LED in the very bottom right hand corner which glows
blue during normal operation, flashes blue on/off in standby or glows
red if the screen is powered off. The back of the screen is enclosed in a
black plastic case with air vents to help dissipate heat from the
backlight and screen.
Above:
front views showing the base of the stand and design. Click for larger
versions
The stand has a triangular shaped base as
shown above which provides a sturdy support for the large, heavy screen.
This is a matte black plastic finish, as is the arm for the stand.
Above:
showing VESA and stand connection (left) and base of the stand (right).
Click for larger versions
The stand provided is packaged separately
and must be connected to the back of the screen by the user. There is a
small screw at the bottom of the stand which releases the hydraulic height
adjustment, and then 4 small screws to attach it to the VESA mount bracket
on the back of the panel as shown above. The arm for the stand is thick
and sturdy and holds up the heavy, large screen well. The base of the
stand has rubber feet on it to help maintain a stable base on the desk.
The screen is VESA compliant as well, but given the heavy weight of the
screen (due to its size and CCFL backlighting unit), it might not be as
easy to wall or arm mount as smaller screens if that is something you want
to consider.
Above: full
tilt range shown. Click for larger versions
The screen offers a wide range of ergonomic
adjustments. The tilt function offers a good range of adjustment as shown
above. It is a smooth movement, but quite stiff to operate. The screen
does at least stay pretty sturdy during movements and it is possible to
get a comfortable setting for a good variety of viewing positions and
angles. On the desk the screen can be a bit wobbly if you knock it. You
will also notice that the screen has quite a thick profile due to the CCFL
backlight unit being used.
Above: full
height adjustment range shown. Click for larger versions
The height adjustments is again smooth, but
stiff to operate, especially when trying to lower the height. At a minimum
height, the bottom edge of the screen is ~35mm from the level of the desk,
and at the maximum height it is ~160mm. This gives a total height
adjustment range of 125mm which is useful and should be sufficient for a
wide variety of viewing positions and uses.
Above: side
to side swivel adjustment shown. Click for larger version
The side to side swivel is again smooth but
stiff to use. The base does remain stationary on the desk though which is
good. There is also a full rotate function to switch between landscape and
portrait modes. That adjustment is actually smooth and easy to use,
although its practicality is questionable on a screen this size.
Nevertheless it's there if you want to use it and it's good to see a full
range of adjustments available from the screen.
A summary of the screens ergonomic adjustments
is shown below:
Function |
Range |
Smoothness |
Ease of Use |
Tilt |
Yes |
Smooth |
Stiff |
Height |
125mm |
Smooth |
Stiff, especially lowering |
Swivel |
Yes |
Smooth |
Stiff |
Rotate |
90° |
Smooth |
Easy |
Overall |
Good range of adjustments although most are
stiff to operate. |
The screen materials are of a pretty good quality and
the design is not bad in my opinion, although perhaps a little industrial in
feel. There is a no audible noise from the screen during normal use even if
you listen closely. However when using specific test images with a large
concentration of text we were able to detect some higher pitch buzzing from
the capacitors. This was not evident during normal uses day to day though.
With a big CCFL backlight unit being used, the screen does get quite warm
during prolonged use, specially from the back and top, and even a little from
the front of the panel.
Above: interface connections on back of the screen. Click for larger
version
The back of the screen provides connections for
the power supply (far left) which is provided with the screen. There are then
video connections for D-sub (VGA), DL-DVI and HDMI. Audio input is provided
although not needed on this model as there are no integrated speakers. The
audio output can be used to take audio sent to the screen over the HDMI
connection if you want to connect it up to some speakers or headphones. You
may notice an MHL connection on the far right but this is not active or used
on this model.
OSD Menu
Above: views of
OSD operational buttons
The control of the screen and the OSD is possible
through a set of 7 buttons located on the back edge of the screen, on the right
hand side if you are facing the front. Because of their location, you have to
reach behind the screen to use them, and at first it can be a little tricky to
figure out which buttons you are using and what they do. After a few uses, you
do get used to it, although it's a little tricky sometimes and not very
intuitive.
The top round button is the power on/off button.
The 'source' button gives you quick access to switch between the input sources.
The 'menu' button takes you into the main OSD which we will look at in a moment.
The right facing arrow (as viewed in the photo above) gives quick access to
switch between the aspect ratio modes available (wide and 4:3).
The left arrow controls the volume if you're
sending audio through the screen over HDMI and have something connected to the
audio output. The up arrow has no quick launch option, but the down arrow gives
you quick access to the brightness and contrast controls as shown above.
Accessing the main menu presents you with the
above set of options. The 'bright/cont' section is exactly the same as the quick
launch access we talked about above. 'Positioning' and 'image settings' relate to
the use of D-sub analogue connections and are greyed out here since we were
using DVI to connect the screen.
The 'color settings' section gives you access to 3
colour preset modes (normal, reddish and bluish), and a further user
configurable mode with control over the RGB levels. Oddly the screen does come
by default in the bluish mode which looks overly cool. We will look at this more
in the following sections.
The 'OSD' section lets you control a few things
related to the OSD itself.
The language section has a few options and
thankfully, despite being a Korean model, the screen came in English out of the
box to at least make navigation easy /possible.
The last 'Misc' section has an option to reset the
screen settings through the 'initialize' function. There is also control for the
aspect ratio options (wide and 4:3 modes available). The DCR option is greyed
out and seems to not be available on this screen, despite some specs suggesting
it should be.
All in all the OSD was reasonable in its options
although there wasn't a massive range of things to alter. There were a couple of
preset modes, but none specifically designed for different uses. Navigation was
easy enough once you'd gotten the hang of using the buttons tucked away behind
the right hand edge of the screen, but that did take some getting used to.
Power Consumption
In terms of power consumption the manufacturer
doesn't seem to list any specific figures. We carried out our normal tests to
establish its power consumption ourselves.
|
State and Brightness
Setting |
Manufacturer Spec (W) |
Measured Power Usage
(W) |
Factory Default (75%) |
- |
125.8 |
Calibrated (29%) |
- |
63.4 |
Maximum Brightness (100%) |
- |
153.4 |
Minimum Brightness (0%) |
- |
61.7 |
Standby |
- |
1.0 |
|
We tested this ourselves and found that out of the
box the screen used a very high 125.8W of power while at its default brightness setting. At
the maximum brightness level the screen used 153.4W of
power, and at the lowest setting this was measured at 61.7W. Once calibrated we
had reached a power consumption of 63.4W which had been once the screen had been
set to achieve a luminance of 120
cd/m2. During
standby the screen uses 1.0W of power.
We have plotted the results of these measurements
on the graph below. As you can see, compared to a lot of modern screens the
power consumption is very high here. That is due to the use of a CCFL backlight
unit which consumes a lot more power than W-LED (and GB-LED) equivalents. It's
consumption is comparable to models like the Dell 3008WFP and Hazro HZ30Wie
which are also CCFL based 30" models.
Panel and Backlighting
Panel Manufacturer |
LG.Display |
Colour Palette |
1.07 billion |
Panel Technology |
H-IPS |
Colour Depth |
10-bit |
Panel Module |
LM300WQ5-SLA1 |
Colour space |
Wide Gamut |
Backlighting Type |
WCG-CCFL |
Colour space coverage (%) |
102% NTSC, 98.2% Adobe RGB, 100% sRGB coverage |
Panel and Colour Depth
The Achieva Shimian QH300-IPSMS sample we tested utilises an
LG.Display LM300WQ5-SLA1 H-IPS panel which is capable of producing 1.07
billion colours. According to the detailed panel spec sheet this is done with a
10-bit colour depth and there is no mention of
Frame Rate Control (FRC) being used. It should be noted that Achieva do
supply the same screen with different panel revisions being used, although most
at the moment will use some version of the Q5 panel.
The panel offers support for 10-bit content. This gives a colour depth support for 1.07 billion colours. However,
you need to take into account whether this is practically useable and whether
you're ever going to truly use that colour depth. You need to have a full
10-bit end to end workflow to take advantage of it which is still quite
expensive to achieve and rare in the market, certainly for your average user.
This includes relevant applications and graphics cards as well, so to many
people this 10-bit support might be irrelevant.
Panel Coating
The
screen coating on the QH300-IPSMS is an old style AG coating from IPS
panels. It is an older panel and so the AG coating could be described as being
'heavy' or grainy. Some people find this to be problematic when viewing a lot of
light content, particularly white backgrounds of office documents and
spreadsheets. Many people though do not find it an issue and it's been used on
IPS panels for many years. It should be noted that modern IPS panels have
reverted to a lighter, "cleaner" AG coating instead.
Backlighting and Colour Gamut
The screen uses a wide colour gamut CCFL
(WCG-CCFL) backlight unit which offers a colour space covering 102% of the NTSC
reference. Some modern screens have begun to use GB-LED backlighting to offer
wide colour spaces (Dell U2713H, U2413 and U3014 for instance), but these older
WCG-CCFL units have been widely used. It can offer a colour space equivalent to
98.2% of the Adobe RGB reference and covers 100% of the sRGB reference.
PWM Flicker Tests at Various
Backlight Brightness Settings
We tested the screen to establish the methods used
to control backlight dimming. Our in depth article talks in more details about a
common method used for this which is called
Pulse Width Modulation (PWM). Previously we have used a camera based method
as described in the article to capture results at brightness settings of 100, 50
and 0. We now have a more advanced photosensor + oscilloscope system which
will allow us to measure backlight cycling with more accuracy and ultimately
more ease. These tests allow us to establish 1) whether PWM is being used to
control the backlight, 2) the frequency at which this operates if used, and 3)
whether a flicker may be introduced or potentially noticeable at certain
settings. The higher this frequency, the less likely you are to see artefacts
and flicker. The duty cycle (the time for which the backlight is on) is also
important and the shorter the duty cycle, the more potential there is that you
may see flicker. Please remember that not every user would notice a flicker from
the backlight but it is something to be wary of. It is also a hard thing to
quantify as it is very subjective when talking about whether a user may or may
not experience the side effects. We are able to at least measure the frequency
of the backlight using this method and tell you whether the duty cycle is
sufficiently short at certain settings that it may introduce a flicker to those
sensitive to it.
100%
50%
Above scale = 1
horizontal grid = 20ms
0%
0% (zoomed)
Above scale
(left) = 1
horizontal grid = 20ms
(right) 1 horizontal grid = 5ms
At a setting of 100 there was a constant voltage
applied to the backlight as you might expect. However, as you started to lower
the brightness PWM was being used for the dimming straight away. At a
setting of 50% the fluctuations in the oscilloscope graph became more obvious
and as you reduced the brightness further they became more pronounced as the
duty cycle became shorter. PWM was
used to dim the backlight all the way down to 0%. From the tests it was possible
to work out the PWM frequency which was a pretty low 180Hz. However, being CCFL
based, the possible flicker produced may be less noticeable than an LED screen
with similar frequency, since the light does not turn on and off as quickly, and
shows a smoother brightness output. If users are worried about flicker or particularly
susceptible to it, then you need to be aware of the use of PWM here.
Pulse Width
Modulation Used |
Yes |
Cycling
Frequency |
180 Hz |
Possible
Flicker at |
|
100% Brightness |
No |
50% Brightness |
Yes |
0% Brightness |
Yes |
Testing
Methodology
An
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 disabled any previously active
ICC profiles and gamma corrections. The screen was tested at default factory settings using the DVI interface, and analysed using
an
X-rite i1
Pro Spectrophotometer (not to be confused with the new i1 Display Pro
colorimeter) combined with
LaCie's Blue Eye Pro software suite. An NEC branded and customised X-rite i1 Display 2 colorimeter was
also used to verify the black point and contrast ratio since the i1 Pro is less
reliable at the darker end.
Targets for these tests are as follows:
-
CIE Diagram - validates the colour space
covered by the monitors backlighting in a 2D view, with the black triangle representing the
displays gamut, and other reference colour spaces shown for comparison
-
Gamma - we aim for 2.2 which is the default
for computer monitors
-
Colour temperature / white point - we aim
for 6500k which is the temperature of daylight
-
Luminance - we aim for 120
cd/m2, which is
the recommended luminance for LCD monitors in normal lighting conditions
-
Black depth - we aim
for as low as possible to maximise shadow detail and to offer us the best
contrast ratio
-
Contrast ratio - we aim
for as high as possible. Any dynamic contrast ratio controls are turned off here
if present
-
dE average / maximum -
as low as possible.
If DeltaE >3, the color displayed is significantly different from the
theoretical one, meaning that the difference will be perceptible to the
viewer.
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.
Default Performance and
Setup
Default settings of the screen were as follows:
Monitor OSD Option |
Default Settings |
Brightness |
75 |
Contrast |
94 |
Preset Mode |
Bluish |
RGB |
n/a (locked) |
Achieva Shimian QH300-IPSMS - Default Factory Settings
|
Default Settings
Standard Mode |
luminance (cd/m2) |
253 |
Black Point (cd/m2) |
0.36 |
Contrast Ratio |
644:1 |
For some reason the screen comes out of the box in the 'bluish'
preset mode, although there were other modes available which we will test
in a
moment. Default setup of the screen felt too bright which is pretty standard for
modern screens but can be easily controlled of course via the brightness
control. You could immediately spot the use of the wide gamut backlight as well, with colours looking more saturated and vivid than a
normal standard gamut screen. Reds and greens in particular looked more vivid
and more exaggerated. This is common for wide gamut screens of course. Some
people actually prefer the more saturated colours for things like gaming and
movies, even if it's at the cost of accuracy. The colour temperature did feel
too cool, perhaps not surprising when the screen is set in the bluish mode by
default.
The
CIE diagram on the left of the image confirms that the monitors colour gamut (black
triangle) extends considerably beyond the sRGB colour space (orange triangle),
especially in green shades. This is representative of the screens wide gamut and
102% NTSC colour space coverage. There was also a fair amount of over-coverage
in reds and some in blues too.
It should be noted that the QH300-IPSMS offers no
emulation for smaller colour spaces and so the screen must always be used in
wide gamut mode. As a result, you need to consider whether you want a wide gamut
screen and whether you intend to work with wide gamut content. If you do, and
therefore need a wide gamut screen then this is of course fine, and the screen
quite closely matches the popular Adobe RGB space in fact as the below tests
confirm. If you are working simply with "normal" sRGB content then viewing that
on a wide gamut screen can lead to oversaturation of colours, and certain shades
can look unrealistic or too neon. Reds and greens for example can look very
bright and skin tones can look strange. Some users actually like the bright,
vivid colours anyway especially in games and movies, but others who are looking
for accuracy and who don't want to deal with the complications of a mis-match
between their workflow and their screen may instead want to consider a monitor
with a standard sRGB gamut. Some rival monitors with wide gamut support offer
sRGB emulation modes which can at least offer the user the ability to switch
between the two if needed. Because of the drive to keep costs at a minimum,
there is no emulation mode provided here.
We have also provided a comparison of the
screens native colour space against the wider Adobe RGB reference. You can see that it extends
beyond the Adobe RGB reference as well in some shades, particularly reds and
some greens, but does fall
slightly short in other parts of the green spectrum, giving rise to the 98.2% Adobe RGB
coverage detailed in the panel spec sheet.
Default gamma was recorded at 2.3 average, leaving
it a little out with a 3% deviance from the target of 2.2 which wasn't too bad. White point was
too cool as we had suspected, being measured at 9174k, and being 41% out from
our target of 6500k. Note that we are using a
spectrophotometer to make these measurements which is not sensitive to the wide
gamut backlight as some colorimeter devices can be. When using a standard gamut
colorimeter not designed to work with modern backlighting units like W-LED,
WCG-CCFL and GB-LED there can be a typical deviance of 300 - 600k in the white
point measurement which is why some sources may refer to a different white point
in this test incorrectly.
Luminance was recorded at a bright 253
cd/m2 which is
too high for prolonged general use. The screen was set at a default 75%
brightness in the OSD menu but that is easy to change of course to reach a more
comfortable setting. The black depth was 0.36 cd/m2, giving us a
fairly mediocre (for an IPS panel) static contrast ratio of
644:1.
Colour accuracy was poor in this measurement but
this is a result of the monitors native gamut, being much wider than the
reference sRGB. DeltaE was recorded at 4.1 average, with maximum of 10.4.
Testing the screen with various gradients showed smooth transitions with no sign
of any banding thankfully. The usual slight gradation was evident in darker tones as
you will see from most monitors.
Colour Temperatures
The QH300-IPSMS features a range of colour
temperature
presets within the OSD 'color settings' menu as shown above. There are options
for normal, reddish (warmer), bluish (cooler) and user. The user option allows
you to manually control the RGB channels which will be useful for calibration in
a moment. We measured the screen
with the X-rite i1 Pro spectrophotometer in each of the preset modes to establish
their colour temperature / white point out of the box. All other settings were left at factory defaults and no
ICC profile was active. The results are recorded below:
Preset Mode |
Measured
Colour temperature |
Deviance from
6500k Target |
Contrast Ratio |
Normal |
7962k |
22% |
711:1 |
Reddish |
6933k |
7% |
741:1 |
Bluish |
9174k |
41% |
644:1 |
User |
7008k |
8% |
687:1 |
We had already seen that the default bluish mode
was too cool, being 41% out from our 6500k target. The normal mode was still
too cool as well, being measured at 7962k and still being a long way off (22%)
from the target. The Reddish mode was actually the closest to the desired
white point at 6933k and being only 7% out from the target. So it seemed that
this mode wasn't actually a "warmer" mode, where you might expect a colour
temperature nearer to 5000k for example, but instead was set up to be quite
close to the 6500k white point we were aiming for. In fact a little too cool
still. The user mode was very
similar to the reddish mode (7008k, 8% out) but could be adjusted manually by
changing the RGB levels for calibration. As a side note, contrast ratio was
actually better in the other preset modes than we'd seen in the default
"bluish" mode which was good. Still not great for an IPS panel, but some
improvement at least.
Calibration
We used the
X-rite i1 Pro spectrophotometer combined with the LaCie Blue Eye Pro
software package to achieve these results and reports. An NEC branded and
customised X-rite i1 Display 2 was used to validate the black depth and contrast
ratios due to lower end limitations of the i1 Pro device.
Monitor OSD Option |
Calibrated Settings |
Brightness |
29 |
Contrast |
100 |
Preset mode |
User |
RGB (Gain) |
80, 75, 78 |
Achieva Shimian QH300-IPSMS - Calibrated Settings
|
Calibrated Settings, Custom Color mode |
luminance (cd/m2) |
114 |
Black Point (cd/m2) |
0.16 |
Contrast Ratio |
712:1 |
We first of all reverted to the 'user' preset
mode in the OSD menu to allow us access to the individual RGB channels. Adjustments were made during the process to the brightness control,
and to the RGB channels as shown in the table above. This allowed us to obtain an
optimum hardware starting point and setup before software level changes would be
made at the graphics card level. This would help preserve tonal values and limit
banding issues. After this we let the software carry out the LUT adjustments and create an
ICC profile.
Average gamma had been corrected to 2.2 according to the initial test, correcting the default
3% deviance we'd
found out of the box in the bluish mode. The white point was also
corrected to 6591k, leaving only a very small 1% deviance now, but certainly
correcting the overly blue image we had observed before. Luminance had also been
improved thanks to the adjustment to the brightness control, now being measured
at 114
cd/m2. We had
set a target in the calibration as normal for 120 cd/m2 but there is
a significant drop in the backlight intensity for some reason between a setting
of 30% (162 cd/m2) and 29% (113 cd/m2), which we will
discuss in the
brightness and contrast stability section of this review. As such, we didn't
want to set the brightness at 30%, which was too high, as it would cause the
software profiling to artificially reduce the luminance and crush the already
mediocre contrast ratio. We went with a setting of 29% brightness which resulted
in a luminance after calibration which was 114 cd/m2.
This gave us a calibrated black depth of 0.16 cd/m2, and a
static contrast ratio of 712:1 which was moderate for an IPS panel, but not
great by any means. Colour
accuracy had also been corrected nicely, with dE average of 0.4 and maximum of
1.8. LaCie would consider colour fidelity to be excellent.
Testing the screen with various colour gradients
showed mostly very smooth transitions. There was some slight gradation in darker tones
and some very slight banding introduced due to the adjustments to the graphics
card LUT from the profilation of the screen. Nothing major at all though.
You can use our settings and
try our calibrated ICC profile if you wish, which are available in
our ICC profile database. Keep in mind that results will vary from one
screen to another and from one computer / graphics card to another.
Calibration
Performance Comparisons
The comparisons made in this section try to give
you a better view of how each screen performs, particularly out of the box which
is what is going to matter to most consumers. When comparing the default factory
settings for each monitor it is important to take into account several
measurement areas - gamma, white point and colour accuracy. There's no point
having a low dE colour accuracy figure if the gamma curve is way off for
instance. A good factory calibration requires all 3 to be well set up. We have
deliberately not included luminance in this comparison since this is normally
far too high by default on every screen. However, that is very easily controlled
through the brightness setting (on most screens) and should not impact the other
areas being measured anyway. It is easy enough to obtain a suitable luminance
for your working conditions and individual preferences, but a reliable factory
setup in gamma, white point and colour accuracy is important and not as easy to
change accurately without a calibration tool.
From these comparisons we can also compare the
calibrated colour accuracy, black depth and contrast ratio. After a calibration
the gamma, white point and luminance should all be at their desired targets.
Default setup of the QH300-IPSMS was ok in some
regards, with gamma at least being close to the 2.2 target (3% deviance). The
white point was far too cool though and the default "bluish" mode should be
changed straight away at least to the "reddish" mode which is much closer to the
6500k target. This default colour temperature was certainly the worst of the
screens compared above, but thankfully it is easy enough to change with a simple
switch of the preset mode. The added bonus in doing that as well is that the
default contrast ratio improves also. Again, keep in mind this is a wide gamut
screen so its appearance and colours will look different to a standard sRGB
gamut screen.
The calibrated black depth and contrast ratio of
the screen were moderate for an IPS panel really. At 712:1 contrast ratio, it
was pretty similar to the Hazro HZ30Wie which uses the same LM300WQ5 panel
(different revision, but very similar). That was measured a little lower at
679:1. The QH300-IPSMS also compared quite well with other IPS screens like the
Dell S2740L (691:1), Hazro HZ27WC (744:1) and HP ZR2740w v2 (708:1). Some other
modern screens surpassed the contrast ratio of the QH300-IPS such as the Dell
U2913WM (1011:1) but to be honest a contrast ratio of around 700 - 800:1 is
pretty common for this panel technology. The out of the box contrast ratio in
the bluish preset mode was a little lower, but the calibrated contrast ratio was
not too bad compared to many other IPS based screens. Those needing a higher CR
may want to consider other technologies like AMVA as well, which can easily
reach >3000:1 in many cases.
Contrast
Stability and Brightness
We wanted to see how much variance there was in
the screens contrast as we adjusted the monitor setting for brightness.
In theory, brightness and contrast are two independent parameters, and good
contrast is a requirement regardless of the brightness adjustment.
Unfortunately, such is not always the case in practice. We recorded the
screens luminance and black depth at various OSD brightness settings, and
calculated the contrast ratio from there. Graphics card settings were left at
default with no ICC profile or calibration active. Tests were made using an
NEC branded and customised
X-rite i1 Display 2 colorimeter. It should be noted that we used the
BasICColor calibration software here to record these, and so luminance at
default settings may vary a little from the LaCie Blue Eye Pro report.
OSD
Brightness |
Luminance
(cd/m2) |
Black
Point (cd/m2) |
Contrast
Ratio
( x:1) |
100 |
291.29 |
0.46 |
633 |
90 |
283.17 |
0.45 |
629 |
80 |
260.17 |
0.41 |
635 |
70 |
238.52 |
0.38 |
628 |
60 |
221.68 |
0.35 |
633 |
50 |
205.60 |
0.33 |
623 |
40 |
187.33 |
0.30 |
624 |
30 |
162.05 |
0.26 |
623 |
20 |
112.95 |
0.18 |
628 |
10 |
107.17 |
0.17 |
630 |
0 |
104.28 |
0.16 |
652 |
Total Luminance Adjustment Range
(cd/m2) |
187.01 |
Brightness OSD setting controls backlight? |
|
Total Black Point
Adjustment Range (cd/m2) |
0.30 |
Average Static Contrast Ratio |
631:1 |
PWM Free? |
|
Recommended OSD setting for 120 cd/m2 |
29% |
The luminance range of the screen was good on the
whole. At the maximum brightness setting the screen reached 291.29
cd/m2, which was quite a bit lower than
the specified 370 cd/m2, but still more than enough for most users
we're sure. At the lower end of the adjustment range you could reach down to
104.28 cd/m2. This should be ok for most users, but perhaps might not
be dark enough for some who want to use the screen in low lighting conditions.
The total adjustment range of 187.01 cd/m2 was good, but we would
have perhaps preferred a lower minimum brightness and a lower maximum brightness
overall. As we discussed earlier, the backlight dimming is achieved through the
use of PWM and so those prone to any issues with backlight flickering may need
to keep this in mind. Being CCFL backlit, it's perhaps not as big an issue as
with modern LED backlights.
We have plotted the
luminance trend on the graph above. The screen behaves as it should, with a
reduction in the backlight intensity controlled by the reduction in the OSD
brightness setting. This was not a linear relationship though. As you can see
from the graph there seemed to be a sudden drop off in the brightness from a
setting of 30% to 29%. This was a bit unfortunate since it means there's no easy
way from the monitor settings to actually achieve a luminance of ~120
cd/m2. The 30% setting was measured at
162.05 cd/m2, and the 29% setting dropped down to 114 cd/m2.
Not an ideal place in the brightness curve for this odd drop to occur really.
The results shown here were
taken in the default bluish preset mode. Average contrast ratio
was measured was 631:1 which was pretty mediocre
for an IPS panel really. It was stable
across the adjustment range with some small deviations at the lower end of the
brightness scale. Thankfully this contrast ratio is a bit better in the other
preset modes as we've discussed earlier. The purpose of this test really was to
confirm the stability of the contrast as you alter the brightness control.
Viewing Angles
Above: Viewing
angles shown from front and side, and from above and below. Click for
larger image
Viewing angles of the QH300-IPSMS were very good
as you would expect from an IPS panel. Horizontally there was very little colour
tone shift until wide angles past about 45°. A slight darkening of the image
occurred horizontally from wider angles as you can see above as the contrast
shifted slighting. Contrast shifts were slightly more
noticeable in the vertical field where a red-ish hue also appeared, but overall they were very good. The screen
offered the wide viewing angles of IPS technology and was free from the very
restrictive fields of view of TN Film panels, especially in the vertical plane.
It was also free of the off-centre contrast shift you see from VA panels and a
lot of the quite obvious gamma and colour tone shift you see from some of the
modern AMVA and PVA offerings. All as expected really from a modern IPS panel.
Above: View of an
all black screen from the side. Click for larger version
On a black image there was no noticeable white
glow which can be problematic on some IPS panels. Instead there was a slight
blue / purple tint to the black image, but it was actually not too bad as you
can see above. There is no A-TW polarizer on this panel which is rarely used
now in the market but was implemented on some older screens to improve the off
centre black viewing.
Panel Uniformity
We wanted to test
here how uniform the brightness and colour temperature was across the screen, as well as identify any
leakage from the backlight in dark lighting conditions. Measurements of the luminance
and colour temperature were taken at 35 points across the panel on a pure
white background. The measurements for luminance were taken using BasICColor's calibration
software package, combined with the NEC customised X-rite i1 Display 2
colorimeter with a central point on the screen calibrated to 120 cd/m2. Measurements for colour temperature (white point) were taken using
BasICColor software and the i1 Pro spectrophotometer which can more accurately
measure white points of different backlighting technologies. The below uniformity diagram shows the difference, as a percentage,
between the measurement recorded at each point on the screen, as compared with the
central reference point.
It is worth
noting that panel uniformity can vary from one screen to another, and can depend
on manufacturing lines, screen transport and other local factors. This is only a
guide of the uniformity of the sample screen we have for review.
Uniformity of Luminance
The luminance uniformity of the screen was
fairly poor unfortunately in the sample we had. The left hand side of the
screen was significantly darker than the right hand side. There was a
maximum variation of 44.26% which was a lot, from 90
cd/m2
minimum (bottom left) up to 132 cd/m2 (middle right). This may
present a problem for colour critical work but isn't really noticeable day
to day in casual use. This may also vary by unit of course.
Uniformity of White Point / Colour
Temperature
The colour temperature uniformity was measured
based on a centrally calibrated 6500k point. As you can see, the colour temperature was
pretty uniform across the panel with only small deviations across the
screen. There was a maximum of 5.76% deviance between any two points on the
screen. The top left hand region seemed to be a little cooler than the
middle with a 3.72% deviance from the central 6500k. The bottom middle
region was a little warmer with a deviance of ~2%, but nothing significant
really.
Backlight Leakage
Above: All black screen in a darkened room. Click for larger version
As usual we also tested the screen with an all
black image and in a darkened room. A camera was used to capture the result.
There was no obvious backlight bleeding at all to the naked eye and the
uniformity looked very good, even in a darkened room. The camera captured some
slight clouding from the bottom right hand corner, but this was
very minimal and not something which you should notice in practice. A pleasing
result here.
General and Office Applications
The QH300-IPSMS feature a massive 2560 x 1600 resolution
which is a little more vertically than the wide range of 2560 x 1440 res 27"
screens. The pixel pitch of 0.2505mm is very small as a result, and by comparison
a standard 16:10 format 24" model has a pixel pitch of 0.270mm. It is however a
little more than the aforementioned 27" models (0.231mm). Some users may find
the text a little too small to read comfortably, and I'd advise caution if
you are coming from a 19" or 22" screen for instance where the pixel pitch and
text are much larger. Personally I think this pixel pitch is about right by
modern standards, a little easier on the eye than the 27" models but a little
"tighter" than the smaller screens out there. The extra screen size also takes
some getting used to over a few days as there really is a lot of room to work
with. It's actually noticeably bigger than a 27" model as well. The massive
resolution is really good for split screen working, office and general use,
giving you a really big screen area to work with. It is a noticeable upgrade
from a 24" 1920 x 1200 resolution. For those wanting a high resolution for CAD,
design, photo work etc, this is a really good option. The image was very sharp
and crisp and text was very clear using the digital DVI connection. This model
actually supports the full native resolution over VGA as well which was unusual.
Some clarity was lost compared with DVI but it wasn't too bad.
The AG coating is not to everyone's taste, and
this model features the older style "heavy", grainy AG coating. It's not the light
coating used on some modern IPS screens (Dell U3014 for instance in the 30"
sector), but it has been used for a long time and many people are still
perfectly happy with it. It can look a bit grainy and dirty on white backgrounds
in particular, so we'd advise caution if you're worried about it or coming from
a lighter coated or glossy screen. It should be noted that most other 30" models in the
market, with the exception of a couple of new screens like the U3014, use the
same heavy AG coating as well (Dell U3011, Hazro models, HP ZR30W etc).
The
wide viewing
angles provided by the IPS panel technology on both horizontal and vertical
planes, helps minimize on-screen colour shift when viewed from different angles.
The
default setup of the screen was ok in terms of gamma, but white point was far
too cool and the screen was too bright. Thankfully both are easy enough to
correct as we discussed in our earlier sections. One thing you cannot change
though is the colour space of the screen. It is wide gamut by its nature because
of the WCG-CCFL backlight unit, and there are no emulation modes to simulate
standard colour spaces here. As a result, you are always stuck with using the
wide gamut mode, and so you need to think about whether that is something you
want or need. Some people prefer it to standard gamut screen for the more vivid
colours, especially in multimedia uses. But for office and Windows uses it may
prove problematic and lead to oversaturated colours which are undesirable for
some.
Out of the box the luminance was too high and so
you will want to turn this down a fair amount to obtain a setting comfortable to
you in your lighting conditions. A setting of around 29% brightness should give
you a luminance of just under 120
cd/m2 out of the box. The brightness
control affords you a good range of adjustments as well, allowing you to go up
to ~291 cd/m2 and down as low as ~104 cd/m2. Those
wanting to use the screen in low light conditions should find the adjustment
range adequate in most cases although not as low as we've seen from some screens. Another thing to note while we are talking about the
brightness control is that the screen does use
Pulse-Width modulation (PWM) to control backlight dimming at a
frequency of 180Hz. Those who suffer from eye fatigue or headaches associated
with flickering backlights need to keep this in mind although it's not as
problematic on CCFL backlights as on modern LED systems. You may also want to
keep in mind that the power consumption is quite high on this model because of
the CCFL backlight, especially if you were thinking of multiple screens for an
office. There is some feint high pitch buzzing from the screen in certain
conditions, mainly when specifically looking for it using test images with a
large amount of text at once. In normal day to day uses, we didn't notice any
issue.
The screen offers no extras unfortunately such as
USB ports or card readers which can be useful in office environments. There was
however a good range of ergonomic adjustments
available which were a little stiff, but smooth to use. The screen even
offers a rotation function which is probably impractical at this size really. The VESA mounting support may also be useful to some
people although keep in mind the screen is heavy and thick.
Above: photo of
text at 2560 x 1600 (top) and 1920 x 1200 (bottom)
The screen is designed to run at its native
resolution of 2560 x 1600 and at a 60Hz recommended refresh rate. However, if
you want you are able to run the screen outside of this resolution. We tested
the screen at a lower 1920 x 1200 resolution to see how the screen handles the
interpolation of the resolution, while maintaining the same aspect ratio of
16:10. At native resolution the text was very sharp as you can see from the top
photograph. When you switch to a lower resolution the text is larger of course
and the clarity is lost quite noticeably. Use the native resolution wherever
possible.
Responsiveness and Gaming
The QH300-IPSMS is rated by Achieva as having a 6ms G2G response time which implies the use of
overdrive /
response time compensation (RTC) technology, used to boost pixel transitions
across grey to grey changes. There is no user control over the overdrive impulse
within the OSD menu and so we are reliant once again on their factory setup. The
part
being used is the
LG.Display LM300WQ5-SLA1 H-IPS panel. Have a read about response time in
our
specs section if you need additional information about this measurement.
We will first test the screen using our thorough
response time testing method. This uses an oscilloscope and photosensor to
measure the pixel response times across a series of 20 different transitions, in
the full range from 0 (black) to 255 (white). This will give us a realistic view
of how the monitor performs in real life, as opposed to being reliant only on a
manufacturers spec. We can work out the response times for changing between many
different shades, calculate the maximum, minimum and average grey
to grey (G2G) response times, and provide an evaluation of any overshoot present
on the monitor.
We use an
ETC M526
oscilloscope for these measurements along with a custom photosensor device.
Have a read of
our response time measurement article for a full explanation of the testing methodology and reported
data.
On the whole the pixel transitions were reasonably
fast. The average G2G response time was measured at 8.7ms which was a
little slower than the specified 6ms G2G from the manufacturer, but still decent
enough. Some black to grey changes (0-100, 0-150) were a little slower at
~10 - 11ms. There was only minimal difference between the average G2G rise time
(changes from dark to light shades) and the average G2G fall time (changes from
light to dark shades). The changes to white (x-255) and to black (x-0) seemed to
be the fastest, ranging down to 5.6ms in the best cases.
As we begin to measure more screens with the
oscilloscope system we can begin to plot them on a graph like the above for easy
comparison. This shows you the lowest, average and highest G2G response time
measurement for each screen. As you can see, the Achieva performed quite
similarly to the new Dell range overall, just a little bit slower. On the plus
side though....
If we evaluate the Response Time Compensation
(RTC) overshoot then the results are pleasing and there is pretty much no
overshoot evident on the screen. The overdrive impulse is modest enough that it
does not push the pixel transitions too far, and so there are no major issues
like we saw on the Dell screens mentioned above. A good result here.
Transition: 100 - 200 - 100
(scale = 20ms)
The above oscillogram is a classic example of what
we saw. This is from the transition from 100 - 200 - 100 as an example. The rise
and fall times are quite similar here and there is no sign of any overshoot in
either case.
Display Comparisons
The screen was also tested using the chase test in
PixPerAn for the following display comparisons. As a reminder, a series of
pictures are taken on the highest shutter speed and compared, with the best case
example shown on the left, and worst case example on the right. This should only
be used as a rough guide to comparative responsiveness but is handy for a
comparison between different screens and technologies as well as a means to
compare those screens we tested before the introduction of our oscilloscope
method.
30" 6ms G2G
LG.Display H-IPS
In practice the Achieva QH300-IPSMS showed fairly
low levels of motion blur although some was detectable to the naked eye and
picked up in these tests. There was nothing severe and no obvious ghosting which
was good. There was no overshoot detectable either, and we've already confirmed
with our oscilloscope system that this screen is free from such issues
thankfully.
30" 6ms G2G
LG.Display H-IPS
30" 6ms G2G
LG.Display H-IPS
30" 6ms G2G
LG.Display AH-IPS
30"
7ms G2G LG.Display H-IPS
We can compare the QH300-IPSMS then against some
other 30" models we have tested. The
Hazro HZ30Wie is perhaps its closest competitor in terms of design, features
and target audience. It is also using the same LG.Display LM300WQ5 IPS panel,
albeit a slightly different revision. In practice both screens seemed to perform
very similarly, with the Achieva having perhaps a slightly less pronounced
motion blur. The new
Dell U3014 model, also IPS based, showed low levels of blur in these
PixPerAn tests as well, but we know from our more advanced oscilloscope tests
that there is some quite severe overshoot on that model across certain
transitions, which can prove pretty problematic for gaming, and even in some day
to day uses. The older
Dell U3011 was better as it showed no severe overshoot issues, but again had
similar levels of pixel response times and blur to the other 3 models here.
30" 6ms G2G
LG.Display H-IPS
27" 6ms G2G
LG.Display AH-IPS
27" 8ms G2G
LG.Display AH-IPS
29" 8ms G2G
LG.Display AH-IPS
We have also provided a comparison of the
QH300-IPSMS above
against 3 other recent Dell screens we have tested
which also use IPS panel technology. The
Dell U2713H was very similar to the U3014 we have already looked at, having
low levels of motion blur similar to the QH300-IPSMS, but some massive overshoot
problems. The
U2713HM and
U2913WM were much better, being a little faster and free from any such
overshoot artefacts.
30" 6ms G2G
LG.Display H-IPS
27" 12ms G2G
LG.Display H-IPS
27" 5ms G2G
Samsung PLS (Trace Free = 40)
27" 12ms G2G
Samsung PLS (Response Time = Advanced)
We can also compare the QH300-IPSMS against a few of the
other popular 27" 2560 x 1440 resolution models available. The
HP ZR2740w showed slower pixel response times with a more
pronounced blurring to the moving image. This is also reflected in the quoted
12ms G2G response time spec in fact. The
Asus PB278Q had showed very low levels of blur at the optimum Trace Free
setting of 40 and so was a little faster than the QH300-IPSMS here with its
Samsung PLS panel. The
ViewSonic VP2770-LED was quite similar to the QH300-IPSMS in practice when
at its optimum response time setting of 'advanced'.
30" 6ms G2G
LG.Display H-IPS
27" 2ms G2G Chi
Mei Innolux TN Film +144Hz (Trace Free = 60)
24" 2ms G2G AU
Optronics TN Film + 120Hz (AMA = On)
27" 1ms G2G Chi
Mei Innolux TN Film + 120Hz (Over Drive = 0)
22" 3ms G2G Samsung TN Film + 120Hz
We've also included a comparison above against
four very fast 120Hz+ compatible screens we have tested. In all cases these
other screens are using TN Film panels and are aimed primarily at gamers.
Firstly there is a comparison against the Asus VG278HE with its 144Hz refresh
rate. This showed very fast pixel response times and smooth movement thanks to
its increased refresh rate. You are able to reduce the motion blur even more
through the use of the LightBoost strobed backlight which we talked about in
depth in our article about
Motion Blur Reduction Backlights.
Then there is a comparison against the
BenQ XL2420T. This showed very low levels of motion blur, but some dark
overshoot was introduced as a side-effect. The
Iiyama G2773HS was very responsive and even has a quoted 1ms G2G response
time. This showed very low levels of blur and had minimal issue with overshoot.
The
Samsung SM2233RZ performed very well in these tests and showed very low
levels of motion blur also. When 120Hz mode was enabled the overdrive artefacts
evident in 60Hz mode were almost completely eliminated, which is something we
have seen with the BenQ XL2420T as well.
While these pixel response tests show the
QH300-IPSMS to
have reasonably fast transitions and fairly low levels of motion blur, there is something else going on as well here which can't be picked out by the camera. All of these other TN Film models are
running at 120Hz (or higher) refresh rates, which allows for improved 120fps+ frame rates and
the support of
3D stereoscopic content as well. This can really help improve smoothness and
the overall gaming experience so these screens still have the edge when it comes
to fast gaming.
The responsiveness of the QH300-IPSMS was pretty good
overall and we were pleased enough with the results we obtained. We had measured a pretty low average G2G response time of
8.7ms which
was good, and thankfully there was pretty much no overshoot across any of the
transitions. In practice it
didn't feel quite as fast as some popular, slightly smaller models we'd tested like the U2713HM for
instance. It should still be perfectly
adequate for most gaming, but those wanting to play fast FPS or competitive
games may want to consider some of the more gamer orientated 120Hz+ compatible displays out
there. Even better still would be models equipped with
LightBoost systems for optimum motion blur elimination.
On another note many gamers like to use exaggerated
settings to make colours look brighter and more vivid. Wide gamut screens can
serve this purpose well as they natively produces more saturated colours. This
might not be strictly accurate but a lot of people prefer this more vivid and cartoony appearance and so it's useful that the option is available from the
QH300-IPSMS. The only issue is that there is no sRGB emulation function and so
you are stuck with wide gamut all the time.
Additional Gaming Features
Aspect Ratio Control - The screen offers
only two options for aspect ratio control. There is a "wide" setting, which will
always stretch the image to fill the 16:10 aspect screen, and a 4:3 mode which
forces a 4:3 aspect regardless of the input resolution. These options are a
little limited and there's no way to maintain a 16:9, 5:4 or 1:1 pixel mapping
via the hardware. This probably isn't an issue for PC gaming where the graphics
card is likely to be able to handle the aspect ratio control anyway. However for
external devices, games consoles and Blu-ray players for instance, it may be an
issue, especially with 16:9 being such a common and popular format nowadays.
Preset Modes - There are no specific preset modes designed for individual
uses like gaming.
Lag
We have written an in depth article about
input lag and the various measurement techniques which are used to evaluate
this aspect of a display. It's important to first of all understand the
different methods available and also what this lag means to you as an end-user.
Input Lag vs. Display Lag vs. Signal
Processing
To avoid confusion with different terminology we
will refer to this section of our reviews as just "lag" from now on, as there
are a few different aspects to consider, and different interpretations of the
term "input lag". We will consider the following points here as much as
possible. The overall "display lag" is the first, that being the delay between
the image being shown on the TFT display and that being shown on a CRT. This is
what many people will know as input lag and originally was the measure made to
explain why the image is a little behind when using a CRT. The older stopwatch
based methods were the common way to measure this in the past, but through
advanced studies have been shown to be quite inaccurate. As a result, more
advanced tools like SMTT provide a method to measure that delay between a TFT
and CRT while removing the inaccuracies of older stopwatch methods.
In reality that lag / delay is caused by a
combination of two things - the signal processing delay caused by the TFT
electronics / scaler, and the response time of the pixels themselves. Most
"input lag" measurements over the years have always been based on the overall
display lag (signal processing + response time) and indeed the SMTT tool is
based on this visual difference between a CRT and TFT and so measures the
overall display lag. In practice the signal processing is the element which
gives the feel of lag to the user, and the response time of course can
impact blurring, and overall image quality in moving scenes. As people become
more aware of lag as a possible issue, we are of course keen to try and
understand the split between the two as much as possible to give a complete
picture.
The signal processing element within that is quite
hard to identify without extremely high end equipment and very complicated
methods. In fact the studies by Thomas Thiemann which really kicked this whole
thing off were based on equipment worth >100,1000 Euro, requiring extremely high
bandwidths and very complicated methods to trigger the correct behaviour and
accurately measure the signal processing on its own. Other techniques which are
being used since are not conducted by Thomas (he is a freelance writer) or based
on this equipment or technique, and may also be subject to other errors or
inaccuracies based on our conversations with him since. It's very hard as a
result to produce a technique which will measure just the signal processing on
its own unfortunately. Many measurement techniques are also not explained and so
it is important to try and get a picture from various sources if possible to
make an informed judgement about a display overall.
For our tests we will continue to use the SMTT
tool to measure the overall "display lag". From there we can use our
oscilloscope system to measure the response time across a wide range of grey to
grey (G2G) transitions as recorded in our
response time
tests. Since SMTT will not include the full response time within its
measurements, after speaking with Thomas further about the situation we will
subtract half of the average G2G response time from the total display lag. This should allow us to give a good estimation of
how much of the overall lag is attributable to the signal processing element on
its own.
Lag Classification
To help in this section we will also introduce a broader classification system
for these results to help categorise each screen as one of the following levels:
-
Class 1)
Less than 16ms / 1 frame lag - should be fine for gamers, even at high levels
-
Class
2)
A lag of 16 -
32ms / One to two frames - moderate lag but should be fine for many gamers.
Caution advised for serious gaming and FPS
-
Class
3)
A lag of more
than 32ms / more than 2 frames - Some noticeable lag in daily usage, not
suitable for high end gaming
For the full reviews of the models compared here and the dates they were written
(and when screens were approximately released to the market), please see our
full
reviews index.
(Measurements in ms) |
Standard Mode |
Total Display Lag (SMTT
2) |
28.0 |
Pixel Response Time
Element |
4.35 |
Estimated Signal
Processing Lag |
23.65 |
Lag Classification |
2 |
|
Class
2 |
We have provided a comparison above against other models we have tested to give
an indication between screens. Those shown with blue bars represent the total
"display lag" as at the time of review we did not have access to an oscilloscope
system to measure the response time element and provide an estimation of the
signal processing. The screens tested more recently are split into two
measurements which are based on our overall display lag tests (using SMTT) and
half the average G2G response time, as measured by
the oscilloscope. The response time is split from the overall display lag and
shown on the graph as the green bar. From there, the signal processing (red bar)
can be provided as a good estimation.
The Achieva QH300-IPSMS showed an average total
display lag of 28.0ms during the initial tests. This lag was not too severe, but
a bit higher than we had seen from some other recent screens, and represented a little
over 1.5
frames of lag. We measured half the average G2G response time as 4.35ms and so we can estimate
that the signal processing is approximately 23.65ms in this mode, basically 1.5
frames worth. This is probably too high for high level gaming but should be ok
for casual gamers and non FPS type games in many cases.
Movies and Video
The following summarises the screens performance
in video applications:
-
30"
screen size makes it a reasonable option for an all-in-one multimedia screen,
but being quite a bit smaller than most modern LCD TV's of course. As far as
desktop monitors go it is at the very large end.
-
16:10
aspect ratio is less well suited to videos than a 16:9 format screen, leaving
larger borders on DVD's and wide screen content at the top and bottom.
-
2560 x
1600 resolution can support full 1080 HD resolution content easily
-
The
native screen resolution means that some source inputs (especially external
devices) will need to be scaled to fill the screen as many will be standard
1080 HD resolution (1920 x 1080).
-
Digital interfaces support HDCP for any encrypted and protected content
-
As well as DVI there are
also VGA and HDMI available which may be useful for connecting external
devices. HDMI is particularly useful given it is so widely used. No
DisplayPort though which is quite common now.
-
Cables provided in the box
for DL-DVI, but not HDMI or VGA.
-
AG
coating does not cause issues with reflections which glossy coatings can but
is of the "heavy", grainy type. Probably no issue for movies or videos though.
-
Wide
brightness range adjustment possible from the display, including high maximum
luminance of ~291
cd/m2 and a reasonable minimum
luminance of ~104 cd/m2. This should afford you very good control
for different lighting conditions although if you are watching movies in a
very dark environment, the lower level adjustment might not be optimal.
-
Black
depth and contrast ratio are moderate for an IPS panel at 712:1 after
calibration. Shadow detail in darker scenes should not be lost in most cases
unless you are watching a lot of dark content.
-
Dynamic contrast ratio not available on this model.
-
No
specific preset modes available for movies or video.
-
Wide
colour gamut available from the backlighting system, so those who prefer
brighter and more vivid colours for movies and videos can take advantage of
the native gamut mode and benefit. sRGB emulation is not available however so
you are stuck if you prefer standard gamut appearance.
-
Good
pixel responsiveness which should be able to handle fast moving scenes in
movies without issue. No overshoot issues either which is pleasing.
-
Wide viewing angles thanks to IPS panel
technology meaning several people could view the screen at once comfortable
and from a whole host of different angles.
-
Good range of ergonomic adjustments available
from the stand. Should be easy to obtain a comfortable position for multiple
users or if you want to sit further away from the screen for movie viewing.
-
No
noticeable backlight leakage, and none from the edges which is good. This type
of leakage may prove an issue when watching movies where black borders are
present but it is not a problem here.
-
No
integrated stereo speakers on this model but there are audio connections to
output the sound if using HDMI.
-
Limited
range of hardware aspect ratio options with only 'full' and '4:3' available.
May present problems with some external devices possibly especially if they
output 16:9 aspect ratio like many do.
-
Picture in picture (PiP) and Picture By Picture (PbP) are not available.
-
For
PAL sources, we have tested the screen and confirmed it will support
the full native resolution of 2560 x 1600 at 50Hz refresh rate.
Conclusion
The QH300-IPSMS was quite an interesting screen to
test as these Korean models have been popular for quite a few months due to
their low costs. We were expecting a very no-frills display, but we were quite
pleased by some of the options, specs and performance actually. While the design
is quite big and industrial, the build quality was actually pretty good and it
was pleasing to see a good range of ergonomic adjustments from the stand and a
decent enough set of connections provided. Normally these are two areas which
are cut back when cost is a driver, but we were happy that Achieva hadn't
scrimped too much on these important areas.
Performance wise the default setup needed some
tweaking due to its overly cool appearance and bright screen. Those were both
pretty easy to correct, even with the somewhat limited OSD control. The wide
gamut backlight provided bright, colourful, vivid images which many people will
like, especially for multimedia uses. However, the lack of an sRGB emulation
mode for standard gamut content may be difficult for some people. You need to be
aware that this is always a wide gamut screen and to keep costs low, they have
not provided a standard gamut emulation as you might find on some higher end
models. Contrast ratio was a little weak out of the box but improved a bit in
the other preset modes and after calibration, and was actually on par with many
other IPS panels we've tested. The grainy old style AG coating may put off some
people but again that has been used for many years and many people are perfectly
happy with their screens. Response times were good with low levels of blur and
thankfully freedom from any overshoot problems. The lag was a little high for
serious high end gaming, but this isn't really a gamer-orientated screen and
still offers some good all-round performance to handle some more casual gaming
without issue.
Perhaps of most interest here of course is the
price. At a RRP of ~£800 GBP it is quite a bit cheaper than other competing
models like the Dell U3014 (£918) and certainly much less than high-end
professional grade screens like the NEC PA301W (£1404). It makes it an
interesting option if you want a large 30" model with a high resolution and good
all-round IPS panel. Now that they are available from a proper UK supplier, with
a warranty and after-sales support, there is a lot more comfort if you do want
to buy a lower cost screen such as this.
Pros |
Cons |
Low cost option in 30" sector,
now with proper warranty and support options |
No sRGB emulation mode so
always operating as a wide gamut screen |
Good pixel response times with
no overshoot problems |
Lag a little too high for
serious gaming |
Decent ergonomic and
connectivity options |
Mediocre contrast ratio and
black depth |
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