Response Times
A topic that almost always comes up as a problem with LCDs is their slower response times relative to CRTs. There's no doubt that even the best LCDs still exhibit some slight pixel smearing, but the vast majority of users are okay with the level of performance we have available now. Image retention on your retinas also occurs to some extent, so even if you can completely eliminate the smearing effect at the display level you won't necessarily "see" a perfectly crisp transition.
Besides lag at the pixel level, there's also potential for buffering lag within the LCD's image processor before anything is ever sent to the panel for output. This can be particularly noticeable on some HDTVs when connected to a computer, as HDTVs will often do a significant amount of image processing. Whether or not delays are caused by the internal circuitry or by the LCD crystal matrix taking a moment to align itself isn't really important; the end result is what matters, so a display that updates quicker is usually preferred, especially by gamers. However, taking a picture of a display using a high shutter speed still isn't the same as looking at the display in person. LCDs run at a refresh rate of 60 Hz, and we use a shutter speed of 1/60s, the net result being that we will capture an image of the display as it appears over a short period of time as opposed to an instantaneous look at the state of the various pixels.
We have compared previous LCDs to the Dell 2407WFP to determine if there was any additional buffering taking place. Unfortunately, we were unable to perform the same testing with the HP w2207 at this time, so we will have to stick with a picture only showing that display without a baseline comparison to the 2407WFP. Links to previous response time images can be found below.
Acer AL2216W #1 Acer AL2216W #2
Dell 2405FPW #1 Dell 2405FPW #2
Dell 2707WFP #1 Dell 2707WFP #2
Dell 3007WFP #1 Dell 3007WFP #2
Gateway FPD2485W #1
HP LP3065 #1 HP LP3065 #2
The advertised response time of the HP w2207 is "5ms on/off", or if you prefer 10ms TrTf (Time rising/Time falling). HP doesn't specifically list a gray to gray response time, but as the figure is more marketing than anything we might as well call it 5ms GTG. Judging by the pictures that we captured, we can see portions of at least three frames. Accounting for shutter lag and pixel lag, the actual pixel response time is somewhere in the neighborhood of 16-25ms. While that might sound like a lot, for the vast majority of people it won't present any problem, and when actually using the w2207 we felt it was about the same as most of the other LCDs we've reviewed. As always, if you're one of those the people who feel more susceptible to noticing image lag, you might want to check out the display in person at one of the larger retailers before making a purchase.
A topic that almost always comes up as a problem with LCDs is their slower response times relative to CRTs. There's no doubt that even the best LCDs still exhibit some slight pixel smearing, but the vast majority of users are okay with the level of performance we have available now. Image retention on your retinas also occurs to some extent, so even if you can completely eliminate the smearing effect at the display level you won't necessarily "see" a perfectly crisp transition.
Besides lag at the pixel level, there's also potential for buffering lag within the LCD's image processor before anything is ever sent to the panel for output. This can be particularly noticeable on some HDTVs when connected to a computer, as HDTVs will often do a significant amount of image processing. Whether or not delays are caused by the internal circuitry or by the LCD crystal matrix taking a moment to align itself isn't really important; the end result is what matters, so a display that updates quicker is usually preferred, especially by gamers. However, taking a picture of a display using a high shutter speed still isn't the same as looking at the display in person. LCDs run at a refresh rate of 60 Hz, and we use a shutter speed of 1/60s, the net result being that we will capture an image of the display as it appears over a short period of time as opposed to an instantaneous look at the state of the various pixels.
We have compared previous LCDs to the Dell 2407WFP to determine if there was any additional buffering taking place. Unfortunately, we were unable to perform the same testing with the HP w2207 at this time, so we will have to stick with a picture only showing that display without a baseline comparison to the 2407WFP. Links to previous response time images can be found below.
Acer AL2216W #1 Acer AL2216W #2
Dell 2405FPW #1 Dell 2405FPW #2
Dell 2707WFP #1 Dell 2707WFP #2
Dell 3007WFP #1 Dell 3007WFP #2
Gateway FPD2485W #1
HP LP3065 #1 HP LP3065 #2
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The advertised response time of the HP w2207 is "5ms on/off", or if you prefer 10ms TrTf (Time rising/Time falling). HP doesn't specifically list a gray to gray response time, but as the figure is more marketing than anything we might as well call it 5ms GTG. Judging by the pictures that we captured, we can see portions of at least three frames. Accounting for shutter lag and pixel lag, the actual pixel response time is somewhere in the neighborhood of 16-25ms. While that might sound like a lot, for the vast majority of people it won't present any problem, and when actually using the w2207 we felt it was about the same as most of the other LCDs we've reviewed. As always, if you're one of those the people who feel more susceptible to noticing image lag, you might want to check out the display in person at one of the larger retailers before making a purchase.
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jc44 - Thursday, August 2, 2007 - link
Initially that would have been the approx asking price (medical applicatinos I think). They got cheaper as time went on though they were never exactly cheap. The Viewsonic (VP2290B) and Iiyama badged versions got under ~$7000 I think (which was approx twice the price on an Apple 30" at the time). Currently a DG5 (the last iteration) goes for ~$3500 on ebay and a VP2290B is ~$1000.The T221 was the first monitor that made me think "The best LCDs are btter than the best CRTs - now they only have to get cheap enough".
I was really hoping that they would take off and the price would come down to something like the current ebay prices. (And yes I did buy off ebay in the end)
Great Googly Moogly - Friday, August 3, 2007 - link
Aye, they're pretty damn cool. I've yet to see one in the flesh though. You still have to have 2 dual-link cards with it though? Doesn't it use 4 single-link connectors?And isn't the 48 Hz data rate (all 4 links) OK enough? (Yeah yeah, TFTs don't have refresh rates, I know, but there are other ramifications of a slow data rate.)
yacoub - Wednesday, August 1, 2007 - link
Not sure why 22" is starting to become prominent over 20". Must be cheaper to produce because tolerances and processes don't have to be as tight, since they're the same resolution just a larger (and thus more visible) pixel pitch on the 22" (0.282mm). Would rather stick with a 20", or if I want bigger then I'd get a 23-24" with 1920x resolution.Jedi2155 - Wednesday, August 1, 2007 - link
When comparing TN 20" versus a 22" panel with around $50 difference, i'd definitely go for the 22" mainly due to the larger screen space which makes games and movies more life-like.Sure the resolution hasn't changed, but why do people buy big screens with lower resolutions anyways? Just to get the bigger picture of course.
Oh, I also think there is a typo on Page 5 at the last paragraph.
You mentioned
But shouldn't it be
JarredWalton - Wednesday, August 1, 2007 - link
I corrected the Acer/Acer sentence -- HP seemed to be a bit better in the vertical plane. Things for the comment.nilepez - Wednesday, August 1, 2007 - link
I think the difference is that if you buy an 70" HDTV, you're not sitting as close as you are if you have a 42". Besides, a smaller TV with accurate colors trumps a big POS set with crap colors (and I've seen some awful HD monitors).
As a result, if the colors are better on the 20", I'd go with a 20".
JarredWalton - Wednesday, August 1, 2007 - link
I think a lot of the better 20" LCDs were IPS or PVA, which might account for the prices as well. Dell I'm pretty sure was IPS on the 2005FP (and FPW?). I think the cheaper 20" LCDs are now also using TN panels. Could be that they can only get the same amount of 22" or 20" panels out of a modern glass substrate, though... I haven't looked into it closely.Spoelie - Wednesday, August 1, 2007 - link
P-MVA and A-MVA are disregarded in the article, even though they are among the best 'overal' monitor technologies, for 20" at least. Second fastest response time, 8 bit color, best movie picture quality, homogeneous viewing angles. It's superior to PVA anyway.JarredWalton - Wednesday, August 1, 2007 - link
I thought MVA and PVA were similar and only certain patents created separate names. Guess not. :) I have never actually tested an MVA panel to my knowledge, and most high-end panels use IPS these days. The next tier uses PVA, and then the lower quality stuff uses TN. The one of the days, though, I will hopefully get the chance to test an MVA panel in person.mostlyprudent - Wednesday, August 1, 2007 - link
I have been using an HP LP series LCD which uses (at least when I bought it) an S-IPS panel. I could never go back to a TN or other panel with less acurate color display.