Overview of Features and Specifications

Before we get to the specifics of the Gateway FPD2485W, it's important to have some understanding of what makes for a good display. There are many factors to consider, and intended use will play a role. Here's a brief overview of the commonly quoted specifications and what they actually mean.

Brightness: This is generally a well understood measurement. Brightness is typically measured in candelas per square meter (cd/m 2 ) or "nits". Having a brighter display is usually preferable to most people, but there is definitely such thing as a display that is too bright. LCDs have really caused some confusion in this area, as brightness levels have shot up in order to compensate for poor black levels. 100 nits is pretty typical of most CRTs, give or take, and 400 nits is probably as bright as you would really want for prolonged computer use. Staring into an ultra-bright display for hours a day can be uncomfortable, so unless your computer environment tends to be brightly lit you'll almost certainly be reducing the maximum brightness. Depending on the technology in use, it's also worth mentioning that running a display at maximum brightness levels can cause the backlights to burn out quicker.

Contrast Ratio: Contrast ratio is often grossly misunderstood due to misleading marketing. Getting a good contrast setting from displays is further complicated by the lack of proper adjustment options on many devices, and personal preference plays a part. The contrast ratio is simply the brightness level of pure white divided by the brightness level of pure black. In the real world, contrast ratio is always infinity - black is 0 and dividing by 0 is equal to infinity. Contrast ratios became meaningful with displays like LCDs where pure black (0 cd/m 2 ) was not possible, and higher ratios are generally better. The problem with such a generalization is that a display with 1000 nit whites and 1 nit blacks has a 1000:1 contrast ratio, while a 100 nit white and 0.1 nit black produces the same contrast ratio of 1000:1. It is usually better to get a high contrast ratio by having very dark blacks than by having overly bright whites, but the brightness and contrast ratio should be viewed as a combined unit where you want to keep the brightness somewhere in the range of 200-400 nits depending on environment while still achieving a high contrast ratio.

Response Time: Pixel response time gained popularity after problems with early LCD displays. Maybe it was discussed in the early days of computers, but most CRTs were simply fast enough that no one thought about pixel response times. The response time is the time required to change from one color to another color; most companies rate it as the time to stabilize to within 5% of the target color. The problem with response times is that you also have to know whether you're changing from black to white/white to black (TrTf), or whether you're looking at gray-to-gray (GTG) times. GTG transitions are more common than black/white transitions, but both are important - consider how often you see black text on a white background, for example. Unfortunately, response times are another widely abused specification, with many companies only reporting the best case scenario rather than an average response time. Also note that TrTf would be roughly twice the GTG time for any given panel, since GTG only involves one transition while TrTf requires two. It is important to know whether a display will bother you with "smearing" - i.e. slow pixel response times - but that ends up being mostly a personal preference with modern LCDs.

Viewing Angle: Viewing angle is the angle at which you can still see the image "properly". This is doubled, since viewing angle actually describes the arc in which you can still see the proper output, and horizontal and vertical components are often listed separately. For computers, viewing angle isn't very important at all, as you're almost always sitting in front of the display. TVs where you may be watching with a group of people can use a larger viewing angle, but even then anything more than a 90 degree viewing angle should be sufficient - after all, it's not fun to watch TV from an oblique angle even if you still see the proper colors. Unfortunately, as with many of the other specifications, what qualifies as a "properly viewable" image is up for debate. In some cases, companies have been known to rate viewing angle as being able to see 10% of the requested brightness. Our display reviews will list the manufacturers' stated viewing angles, but we will only bring it up as a cause for concern if we find the viewing angle to be extremely narrow.

Color Depth: Depending on the sort of work you're doing, the need for high precision color depths varies. Most displays have a set number of intensities that they can display for red, green, and blue, and this is almost always a power of 2. (Technically LCDs function by passing varying light intensities through a color filter, but the net result is the same.) A 6-bit display can show 26 (64) different intensities while an 8-bit display can do 28 (256) intensities. With separate RGB values, you can then cube that number to get the total color space. 643 = 262,144, 2563 = 16,777,216, etc. While most people will agree that 6-bit is insufficient - even with dithering to approximate a larger color space - anything more than 8-bit per channel output starts to become more hype than substance. Lower color depths can also result in banding, where the transitions between various colors become visible even when they're not supposed to be.

Color Accuracy: Out of all of the factors to consider when looking at a display, this is going to be one of the most important. Unfortunately, accuracy is rarely a reported specification, in part because it is far more difficult to measure but also because it can vary from display to display. Getting accurate colors from a display can be achieved in several ways. The first is to basically just go with whatever defaults an LCD comes with, which usually means that the colors will be wildly inaccurate. A slightly more sophisticated approach is to use software to try and help you calibrate the contrast and brightness, and you can take it a step further by adjusting color intensities as well. This is what is known as "calibrating by eye" and is what most people end up doing. The best way to calibrate your display is to get a hardware colorimeter and appropriate software to help you adjust the various display settings, but unfortunately this costs money and most people don't care enough about color accuracy to go that far. Image professionals, on the other hand, would be well served by purchasing some form of color matching/calibration hardware/software.

Other Factors: Arguably the most important factors for a lot of people when looking at a new display are going to be the size and the price. All of the specifications may look great, but if a display costs several thousand dollars the target market is greatly reduced. Likewise, a decent display sold at a very competitive price is going to be far more attractive to a lot of people. That said, it's not too surprising that lower-cost displays tend to vary much more in terms of overall quality - one unit might produce great colors and the next could be highly inaccurate. Part of the reason for this is that quality control isn't as much of a concern. Build quality is also often affected by lower costs, with some cheap displays coming with very flimsy stands and/or enclosures. LCDs in particular can also develop pixel defects - individual pixels or sub-pixels that are stuck in a single position, resulting in either black dots or bright dots - and manufacturer warranty and replacement policies are something else to we will evaluate. We will also look at the ability of the LCDs to function in non-native resolutions, although most people will want to run at native resolution so this isn't a huge concern. On-Screen Displays (OSDs) and any other noteworthy features will also be mentioned.

Now let's take a look at the features and performance of the Gateway FPD2485W to see how it fares.

Index Specifications
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  • anandtech02148 - Thursday, February 22, 2007 - link

    I find the Westinghouse 37 lcdtv eye candies with all the pluggins you could want, for pc, consoles and whatever hi-def format.
    and it has native resolution as this Gateway 24.
    Dell is losing it touches lately, Westinghouse got a niche here they should runaway with it.
    Reply
  • JarredWalton - Thursday, February 22, 2007 - link

    I'll see if I can get one for review - I'd certainly like to check out some of the LCD-TVs that can function as computer displays. Of course, pixel pitch is going to be a lot larger on a 37" 1080p display, and while that may be fine for HDTV and gaming purposes, it probably isn't the best for close up computer work. Reply
  • Welshtrog - Thursday, February 22, 2007 - link

    I am looking at these displays with interest, however there is nothing in this review that will change my mind regarding retaining my 19" Flat screen CRT just yet, It has good colour accuracy after being set up and no stuck pixels Reply
  • JarredWalton - Thursday, February 22, 2007 - link

    I've got two decent 19" CRTs still (NEC FE991 and Samsung 997DF), and honestly I can't stand using them after I switched to a 24" LCD 18 months ago. I still get irritated by image tear caused by the 60Hz refresh rate, but in all other areas I'm a lot happier with larger LCDs over CRTs. Part of that is simply the expanded screen size, but the reduced footprint is nice as well. I bailed on CRTs a few years ago and haven't really missed them, although I can certainly understand the hesitation. The $600+ prices doesn't help either. :) Reply
  • Justin Case - Thursday, February 22, 2007 - link

    The review doesn't address this. I know it says "16 million colors", but all manufacturers say that, and 90% of them use 6-bit panels with automatic dithering. The fact that this is an active matrix TFT, coupled with the very low resposne time suggests that this is a 6-bit panel, like the majority.

    This means more banding and dithered midtones. Which is probably fine for "office" use, but it makes the LCD unusable for photo work (actually, any LCD short of an Eizo CG is pretty much useless for photo work, IMO, and even those just barely manage to match a high-end CRT), and can make games and movies look pretty bad, too.

    To test this, just display a smooth gradient (at the monitor's native resolution) and either look at it very closely or take a photograph of a very small area (about 10 pixels wide), and then increase its contrast until the darkest color is black and the brightest color is white. If you see dithering or banding at the pixel level in the intermediate shades, it's a 6-bit panel.

    Reply
  • Aquila76 - Thursday, February 22, 2007 - link

    It is an 8 bit S-PVA panel, like the Dell and Samsung 244t. It does 'real' 16.7 million colors, but as I stated previously (and as Jarred can attest) it is nowhere near accurate. Reply
  • Justin Case - Thursday, February 22, 2007 - link

    I'd still like to see a "real" test of the screen (by taking a high-speed photo of a small area). Some panels out there do intermeidate colors by flipping between two shades. The panel _accepts_ 8-bit values, but the LCs don't actually have 256 stable transparency levels.

    Not that I'm very interested in this particular model, but I think it would be useful if review sites actually did that, rather than trusting what the manufacturers tell them.

    Even in high-end professional equipment there's a lot of deception. Consumer stuff is even worse (ex., until about a year ago there were almost no real 1920x1080 HDTV sets out there; apart from Sharp, they were all 1366x768 and below, but they all claimed to "support 1920x1080", because they could take it as an input signal).

    Reply
  • strikeback03 - Thursday, February 22, 2007 - link

    meh, the color calibration results aren't great, considering on my laptop I have an average dE of around .6 and only 3 values over 1 (out of the 42 tested by my Eye-One Display 2). I'll probably still pick one up though, as it's the only locally available 24" display.

    Other reviews I read online spoke of crushed blacks which calibration did not correct when viewing movies. Any comments on this?
    Reply
  • Gary Key - Thursday, February 22, 2007 - link

    quote:

    Other reviews I read online spoke of crushed blacks which calibration did not correct when viewing movies. Any comments on this?


    Jarred is currently reviewing the requests/questions and will have responses later today.
    Reply
  • xtknight - Friday, February 23, 2007 - link

    When you calibrate using a colorimeter and accompanying software, it only loads the LUT (lookup table) on to the desktop. When you watch a movie, most of the time you're using overlay, which to my knowledge does not allow the fine tuning needed for a lookup table. With VMR you could potentially view videos calibrated, although the last time I tried this I had some odd 16-240 level compression problem.

    I've been meaning to investigate the overlay "LUT" (or to even find if it exists in the first place). I've seen a function in NVIDIA's control panel API that allows the loading of a LUT onto the overlay surface so I'll see what's up with that.
    Reply

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