Dell 3008WFP-HC - BeHardware
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Written by Vincent Alzieu

Published on February 29, 2008

URL: http://www.behardware.com/art/lire/703/


Page 1

Introduction

Introduction
Price : 1912.40 Euros.

Between its photo and product sheet we can immediately see:
  • the new look borrowed from the 2707WFP,
  • the IPS panel technology which is rare !
  • the 8 ms response time. Letís pray that real reactivity is better, if not this could be amongst the slowest on the market,
  • the 3000:1 contrast ratio which is way above average,
  • brightness at 370 cd/m≤ which is excessively bright if Dell did indeed opt for this as a default setting,
  • the rich connectivity in addition to an unprecedented Display Port input.
    24 inches = mid-range. In the future, a 30 inch model for everyone?
    The context in which the new 3008WFP-HC arrives has also changed. During the launch of the first 3007WFP two years ago, even 24 inch models seemed oversized ; however this is no longer the case. The latter size is becoming incredibly popular to the point that some models are now found in the entry-level with a price under 300 Euros.

    From the moment that 24íís have taken over the mid-range, a large vacuum was left which demands a new high end product. So the bets are on. Dell is amongst those playing this game and its two possible outcomes:
    - some are gambling on 26/27/28 inch Full HD monitors,
    - others Ė and fewer manufacturers Ė are counting on the 30 inch.

    Surely, the 30íí diagonal appears immense and oversized ; however this was the exact same case for the 24íí two years ago. Therefore, it isnít unreasonable to think that the 30 inch could make its way into usersí homes, especially if we imagine a double use for these products as a monitor and television. The size and video inputs enable this.
    The tests
    We run tests for reaction time in games, delay of display, and video rendering (SD, HD 720p, HD 1080p). We also evaluate ergonomics, viewing angles, the quality of upscaling, and the panel's brightness homogeneity. In short, we look at all aspects of a screen.

    For color fidelity we use the LaCie Blue Eye Pro colorimeter, based on the Gretag tool and combined with the new LaCie software suite. More evolved than the previous version, this helps us to compare a monitorís display quality (color spectrum and DeltaE) in standard settings and after calibration. Results are sometimes surprising as itís often best to take the time to manually adjust colors (or at least contrast, brightness and color temperature).

    The results of our study of 18 standard patches make it possible to create a table visually resituating the variation of colors compared to an ideal grey scale.

    Rather than a response time measurement with an oscilloscope, we photograph the monitor in action. This is an effective way of capturing afterglow. The program used is Pixel Persistence Analyzer (or PixPerAn for those more familiar with it). Pictures showing these ghosting effects are captured with a Canon 350D at a shutter speed of 1/1000 s. We take 50 pictures in burst mode for each test to precisely measure the progression of afterglow between images. Otherwise, we haven't given up on the practical tests in games, HD and DVD video, web surfing, etc.

    Finally, we measure the delay to display images compared to CRT monitors.

    The test computer is self-assembled, has an AMD Athlon 64 3500+ processor and NVIDIA GeForce 7900 GTX card.


  • Page 2
    Ergonomics : Display Port, the base...

    Ergonomics : Display Port, the base...
    There was a change of look and interfaces as well an unprecedented addition: the 3008WFP-HC has a Display Port input. This is the connection that is supposed to rapidly replace the current DVI Ė according to some analysts. Simply put, itís a type of HDMI devoted to computers. Like HDMI, the new connection is compact, without apparent pins (no bending), is digital and simultaneously transmits the image and sound. So if it resembles HDMI so much, why add this connection?

    The group that has developed this norm, the VESA, stresses its free use aspect and also the larger bandwidth which enables attaining 2560x1600 with a connector and simplified cabling. Indeed, HDMI is currently limited to 1920x1200 with a dual link and type B connector (formerly not too common) required to attain 2560x1600. For this reason, only the DisplayPort (expected on the first graphic cards in May 2008) and a Dual Link type DVI will allow support of the 3008WFP-HC in its native resolution.


    From left to right: DVI Dual Link, HDMI, and Display Port

    The Display Port, however, is just a type of input amongst many others and hasnít yet imposed itself. Moving on in the ergonomic aspects of the 3008WFP-HC, there are other video inputs including HDMI (here limited to 1920 x 1200 pixels), YUV, and VGA. Therefore, there is everything needed to relay a DVD/HD player or HD console.

    On the right, we can see two USB ports. There are a total of four on this monitor. The two others are on the left-hand side next to the card reader (USB 2).

    These fine ergonomics are complemented by an extremely attractive design and high level finishing touches. The base is identical to that of the 27 inch launched last year.



    Page 3
    Color rendering and grays

    Color rendering
    As usual, we measured the difference between ideal colors and those actually displayed on the screen. This was done with the help of a LaCie BlueEye Pro, which is actually a Gretag sensor combined with a software suite developed by LaCie. The verdict here: colors arenít accurate and black levels arenít deep enough. Concerning this last area, itís unfortunately a known and recurrent defect of IPS technology while TN and PVA have made considerable progress. These last two types of panels now offer black levels that are about twice as deep at those of an IPS at equal brightness values in white.

    You may recall the larger the difference between actual and ideal colors, the higher the DeltaE value and the less the screen is accurate. More precisely, here is how to interpret the graphs:

    - Delta E > 3 : the desired color is noticeably different from the one on the screen.
    - 2 < Delta E < 3 : color quality is satisfactory, but a graphic designer probably wouldnít be content
    - 1 < Delta E < 2 : colors are accurate.
    - Delta E < 1 : the result is perfect.

    DeltaE by default


    IPS 8 ms : Dell 3008WFP-HC


    Besides color rendering, there is a point that concerns more and more people, depth of black. We took measurements with a constant brightness of 200 cd/m≤ in white and then at 100 cd/m≤.

    Depth of black (cd/m≤) with white at 200 and then 100 cd/m≤


    The deeper black is and the closer to 0, the better. The contrast of images will appear superior on these monitors. After that, color fidelity should be good so that we can truly have the best display.

    The 3008WFP-HC claims to have a contrast ratio of 3000:1 not even in dynamic but in standard mode. Under our sensor, results proved to be much more modest in default settings as well as after calibration due to its washed out blacks. For comparison, good monitors go under 0.20 cd/m≤ while the best have measurements less than 0.15 cd/m≤. In the world of TVs, which is slightly in advance, we measure as low as 0.07 cd/m≤ on certain models equipped with PVA panels. By the way, the same goes for plasmas.
    So in the end the 3008WFP-HC is a bit disappointing in this area.
    More concretely for grey renderingÖ
    Unless you are an expert in monitors (and even then) it is difficult to imagine what these differences can represent. What is the most bothersome, however, is when we can immediately see color dominances on the screen. This can affect all colors but is particularly noticeable in grays where the eye can quickly see when blues or reds are overrepresented.

    Here are the screenís grays which are reproduced as they have been measured by our sensor. For comparison, on the bottom line are the ideal grays.

    Whether the screen you are currently using is calibrated or not, you should still be able to see the differences between the two lines.

    IPS 8 ms : Dell 3008WFP-HC

    What does an average dE94 of 5.5 mean? Typically, this can be a noticeable blue dominance as is the case here. You donít have to be a professional to see the difference between the grays above and below as well as the presence of blue on the top row. In short, with factory presettings colors are not balanced.

    Itís amazing to see in 2008 that some manufacturers still offer screens that are this poorly adjusted out of the box. This is while some entry level 22íís for under 300 Euros come with good color fidelity.

    The argument is that those who opt for such a 30íí for this price will correct colors via calibration. This isnít wrong but it still doesnít mean that we wouldnít prefer to limit the damage and have accurate colors from the start.


    Page 4
    After calibration and homogeneity

    After calibration
    Default settings are disappointing. There is a noticeable dominance in grays while in other colors itís even worse. One good point is that the OSD offers a number of adjustments as well as being well conceived and clear. We take a look at this in more detail on the following page.

    Either way, to more precisely correct colors, the only solution, or at least the most accurate, consists of carrying out a calibration. We put this screen through ours, everything being automatic. The operation takes 5 minutes after which we have the following differences in colors:


    IPS 8 ms : Dell 3008WFP-HC
  • Average difference, dE94 = 0.5.
  • Black level: 0.32.

    Itís better but to be perfect black levels would have to be deeper Ė at least in presettings with a brightness of 200 cd/m≤. This is a comfortable setting and recommended for most uses.

    For those looking for a display as close as possible to their previous CRT or more "paper-like" rendering, take the time to lower the overall brightness. The best settings we found were Brightness at 39 and Contrast at 40. Black then goes down to 0.24 cd/m≤ with an average dE of 1.7. Black levels improve while the contrast ratio and overall color fidelity worsen (although we still have a very good value!).
    Homogeneity of colors
    This time we place the sensor on various points of the panel to verify if the colors are indeed the same everywhere. Or to be more precise, we measure the differences as there always are.

    Itís a process that we reserve for high end screens because this test isnít without its problems. Homogeneity depends on the screenís transportation conditions and small shocks can noticeably affect this quality. Between the boat, truck and then the car trip home, there are many factors beyond the manufacturerís control...

    High end screens should be particularly well packed for exactly this reason. In our opinion, the 3008WFP-HC should be amongst those monitors for which we expect the maximum quality.


    More specifically, between the brightest point (in the center) and the darkest (upper right corner), we measured a difference of 29 %. This is significant but not uncommon and characteristic of classic entry/mid-level screens.
    Once again, we were surprised that such a monitor has rather "normal" and non-exceptional rendering, something we wouldnít expect given its price. This is all the more true because Dell has shown better on its 27íí, the 2707WFP, which only had a maximum difference of only 13%.
    So is this 30 % gap really a problem? Luckily, no, as the transition is progressive and spread out on a very large surface. Unless you display a single color and really look for the differences, this shouldnít bother you.


  • Page 5
    Reactivity and input lag in games

    The reactivity test
    Initially, we wanted to physically measure afterglow with an oscilloscope. We approached an electronics specialist, Tektronics, and they were nice enough to supply us with a sensor + oscilloscope combo of their making. This was to be used to measure the transition from white to light gray, white to a darker gray, gray to black, etc. We came up with some great 3D graphs but the problem was that practical tests (based on a visual evaluation) didnít always match these results. A screen that was judged more reactive with the oscilloscope sometimes appeared to our eyes as being slower than other products. We therefore abandoned this method to come back to more practical, concrete, and in our opinion, realistic tests.

    Our other method put into place since 2005 and based on photos, has proven to be more reliable.


    Hereís the concept in this test: A car moves from right to left at high speed. The movement isnít perfectly fluid and depending on its speed, the car is shown in several successive positions. When this process is sped up, the car goes very fast, positions are very close and the eye perceives a fluid movement.

    The perfect screen
    monitor with two afterglow images

    A monitor without ghosting effects would have previous images completely fading away when a new one appears. This is ideal, however in practice, it's often not the case as images progressively fade. Sometimes up to 5 afterglow artifacts remain on the screen representing the visible white trail behind objects.

    We capture this LCD defect with a camera at a shutter speed of 1/1000 s by taking 50 pictures per test. We then can see a monitorís ghosting effects, or the carís position in the entire process from the moment when afterglow is at its maximum, up until when the next image is about to be created and the previous image is the least visible.

    Here are the two extreme states between which each monitorís afterglow can oscillate.


    IPS 8 ms : Dell 3008WFP-HC

    Frequency of the two states:


    We therefore always have a colored afterglow image behind the main image and half the time an additional transparent one.

    For comparison, here is what we find on a good quality TN 2 such as a Iiyama 22íí 2 ms:


    There can be more transparent afterglow images but this isnít a problem as this only slightly increases visible afterglow. It is especially the colored ones that are a factor and determine if a screen is more or less good in this area.
    For this reason, the Dell 3008WFP-HC is obviously behind in reactivity. In addition, all of the Ďíaverageíí performances start add up here and become a problem. First is was in colors, then depth of black, brightness homogeneity, and now reactivity.

    By the way, here is the reactivity of an entry level TN 5 ms :


    The 3008WFP is therefore not all that catastrophic and it is more half-way between the best and worst monitors at this time. However, note that its 8 ms announced response still does better than a TN 5 ms. After all, they are just numbers...
    Input lag in games
    If you didnít already know, almost all LCD monitors have a small delay in display. To measure this, we photograph a chronometer which is precise to 1/1000th of a second displayed in clone mode on our reference CRT and the LCD we are testing. We take 12 consecutive differences, eliminating the two extremes and then find the average delay.

    For this test, we deactivate graphic card / screen synchronization to capture a more precise result instead a value that is rounded to the nearest image. For this reason, the resulting measurements are not dependent upon the fps value. An LCD functions at 60 Hz (even those that claim 75 Hz) and so 17 ms equals an average delay of a single image. In the same way, 33 ms equals 2 images. This may not seem like much, however, to an on-line gamer it could make a world of difference. For example, an adversary with an LCD or CRT will see his character two images before him. This can be compounded by the fact that the mouse can add another 1 to 8 ms (except very poor ones), and the graphic card adds a half image delay (at best and actually this can be 5 to 50 ms). More specifically in our research, we found that this can be a cumulative delay of 110 ms or 6.5 images. In this case, it is indeed noticeable and even bothersome for some gamers. For more details on this subject, see our article on LCD images delayed compared to those of CRTs ? Yes !.


    IPS 8 ms : Dell 3008WFP-HC

    Once again, the 3008WFP-HC scores low while a growing number of screens come with no input lag, even in the entry-level. This screen is consistently 3 images behind.


    Page 6
    Viewing angles, rendering in movies

    Viewing angles
    We take pictures of the monitors from a 50į angle from all sides. The claimed viewing angles in a productís characteristics are often exaggerated especially for TN screens.

    There are three types of technologies to choose from: TN, MVA and PVA, the last two being closely related. We could also add ASV Ė a variation of MVA from Sharp, in decline which we really only find in TVs.

    First of all, lateral viewing angles with IPS technology are by far the best. Next usually come monitors with TN panels. In the past (more than 2 years ago), TNs were rather catastrophic from the side angles. Now, it is possible for several people to share a screen, even if they arenít perfectly in front of it. Finally, we have the PVAs and MVAs, which are more or less equivalent. Beyond 40į from both sides, there is a loss of contrast, which however isnít too extreme. In fact, there are only really problems when looking from below.

    Vertical viewing angles : The IPS screen always offers an image that is almost perfect at 50į and even beyond. In this area, other technologies are largely inferior. The PVAs are behind with a rather abrupt loss of contrast with an image that is still visible though not as flattering (black is more gray, white is pale, loss of depth). Itís the same but even more sudden with MVA panels. Finally, we have the TN screen. From above, the image loses all of its contrast. From below, it turns black. This complicates things when you want to use this screen as a TV and depending on the size of viewers, the monitor may have to be inclined.


    IPS 8 ms : Dell 3008WFP-HC

    Here the Dell screen does not disappoint and its viewing angles are truly large! As a reminder, here are the other types of technology for comparison :

    TN 2 ms : Iiyama ProLite E2201W


    PVA 6 ms : Dell 2407WFP-HC


    MVA 8 ms : ViewSonic VX2435wm
    Movie rendering

    The 3008WFP-HC is an IPS and it performs as such ; however, there arenít only advantages here. As we mention above, we like the very large viewing angles this technology offers (there is nothing better). The downside is that it is more subject to shimmering than others and you have to step back from the screen to better enjoy your movies.

    Putting some distance between you and the monitor is even more of a priority because there is no video correction circuitry integrated to this Dell. Itís an option still reserved for televisions and as usual rescaling is dependent on the graphic card. This has slightly improved but we are far from the smoothing and upscaling capabilities of the best TVs. Here all compression defects are indeed visible. You will really have to tough it out if you want watch a divX with this monitor.


    Page 7
    Energy consumption and conclusion

    Energy consumption
    Consumption is measured with the display of a standard photo.

    In the same way we see "Beware of dog " signs, the 3007WFP should have a warning on its package of being a big energy user.


    IPS 8 ms : Dell 3008WFP-HC

    130 Watts at 200 cd/m≤ in white! Itís more than triple the measurement of a normal 22 inch! Itís the equivalent of 11 low consumption light bulbs (11 Watts).

    For comparison here is the energy use of the Iiyama E2403WS, a rather efficient 24 inch:


    TN 2 ms : Iiyama E2403WS
    Conclusion
    The 3008WFP-HC is a great and very practical screen but donít expect high performances. It has poor factory presettings, is subject to latency, input lag, shimmering in movies and it consumes too much energy. If only the inside had gotten as much attention as the exterior!

    There are indeed problems. For this reason, we are a bit frustrated and had the impression of not getting our moneyís worth. In the end, Dell ambitious price isnít on par with the actual qualities of its monitor.

    To this, they could reply : Yes, but you forgot to mention that it is a wide gamut. This was done on purpose!


    The gamut on the 3008WFP


    The wide gamut has started to pop up everywhere. And then manufacturers realized that it is often not a real plus. You have to be meticulous to actually take advantage of it ; use the wide gamut when the source or target are well adapted (a reflex that functions in the Adobe RGB space, a pro color printer, etc.) and then come back to normal settings the rest of the time. This means permanently juggling between two states and therefore two profiles. Without a calibration device, this is a problem!

    So what we really didnít like with this screen were the imprecise factory pre-settings. As much as the user is given the option to switch between two modes, these should have been more accurate.

    The ultimate question : what does the 3008WFP-HC add compared to the 3007WFP-HC ?Here we have to go back to the test of the former model. More or less this is what we wrote: poor color fidelity with default settings, brightness homogeneity varies roughly 20%, good reactivity, an IPS 6 ms panel, and wide gamut. We precise that at the time, some tests were lacking such as measured contrast and energy consumption. Nevertheless, our conclusion is that the biggest change is only in terms of the bezel and even the price. Itís really just an aesthetic update of its predecessor. So should we be surprised? No. There arenít many 30 inch screens, the demand for them is still low, and their revision is almost inexistent. In short, the panel is the same, or at least it wasnít radically changed and without great surprise, this screenís behavior is more or less identical.


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