To perform these tests, we use a high-speed camera that shoots at 1000 frames per second. Analyzing the video frame-by-frame allows us to observe the exact time it takes to go from a zero-percent signal to a 100% white field.
The pattern generator is placed at the base of the monitor so our camera can capture the precise moment its front-panel LED lights up, indicating that a video signal is being received by the monitor. With this camera placement, we can easily see how long it takes to fully display a pattern after pressing the button on the generator’s remote. This testing methodology allows for accurate and repeatable results when comparing panels.
Since we couldn’t use our Accupel pattern generator with the HP ZR30w, we employed CalPC Client from SpectraCAL to display a white field pattern. We shot the same video, but this time we recorded mouse inputs to determine the panel’s input lag. Since this method is less precise, we averaged five measurements to arrive at the final value. The DoubleSight DS-309w does accept input from the Accupel, so we measured it like we do our other test screens.

For pure response, both panels are near the top of our comparison. We would expect them to be close since they are both based on similar LG IPS panels.
The real litmus test is the absolute lag metric. This is a function of each monitor’s input control PCB.

The HP is fairly snappy like its 27-inch sibling, but the DoubleSight comes in second to last. As with Auria's EQ276W, I didn’t have any trouble playing fast-paced games, though gamers more skilled than myself might notice the delay. We look forward to testing some high-refresh gaming monitors in the near future, but for now, none of the above screens is really intended for those with super-human reflexes. For the vast majority of people, these 30-inch panels will provide an excellent gaming experience.
- 30 Inches And 2560x1600: Two Big-Screen Monitors
- Measurement And Calibration Methodology: How We Test
- Results: Stock Brightness And Contrast
- Results: Calibrated Brightness And Contrast
- Results: Gamma And ANSI Contrast Ratio
- Results: Grayscale Tracking
- Results: Color Gamut And Performance
- Results: Viewing Angle And Uniformity
- Results: Pixel Response And Input Lag
- 30-Inch QHD, Is Bigger Better?
Isn't the ASUS PQ321 already out along with a few other 4K monitors? granted price is a whole other story
You seriously can't see the pixels? I can see them on a 27" 2560x1440, which has smaller pixels. The .25mm range is adequate to me, but really I'd prefer something smaller than the .233mm on the 2560x1440.
When considering something like this for games, don't forget the cost of the video card(s) needed to drive it. A HD7750 may be "sufferable" even up to 1920x1080, but I'm not sure even a HD7770 or GTX650Ti could play newer games on better than "low" settings on one of these.
I have a ZR30W myself, and I would NEVER trade it unless what I'm upgrading to has more than a 2560x1600 resolution.
I've played on all sorts of monitors, and resolution trumps all other specs, unless you're dealing with 30fps or something...
I really wish I would have spent 1200$ on it long ago. Battlefield 3 and other highly graphical games are comparable to nothing else in the world.
The 60hz is not "old tech", it's more than sufficient to run games smoothly if vertical sync is on (even still when it's off). 60 fps is fine, television (pre hd) was 28hz. Anything above 60fps you really don't notice too much.
Oh, and for those looking for 4k tv's to use (I'm way ahead of ya) they only have 30hz refresh rates over the HDMI 1.2 port. We're going to have to wait for the tv's to add another port, wait for the upgrade to HDMI 2.0, or wait for some other solution.
We aren't going to see many 16:10 in the future. the 4K stuff is going to be 16:9 unless someone makes the move to stick with 16:10. However, the difference when it comes to 16:9 with a 2560x1440 and 16:10 2560x1600 is very minimal unless you really really need that extra height!
A properly implemented OSD would blend overlay pixels on-the-fly and add less than 100ns of lag to the process, which would be undetectable. The Viewsonic VP2770 has an OSD and is on par with the fastest LCDs in this roundup for total input-output lag. Having an OSD does not equate to lag.
The art of zero-lag OSDs is very old: countless computer CRTs from the mid-90s have it and TVs have had it for even longer. The OSD locks timing with the H/V sync and substitutes its signal over the relevant areas on-the-fly. With LCDs, this is even easier to do since everything is digital.
What is more likely happening is that "laggy" LCDs are doing extra image processing/enhancement or power-saving tricks such as dynamic brightness adjustments. For dynamic backlighting (power saving trick), the LCD needs to know what the brightest pixel is and then adjust the whole image so it remains the same while matching the brightnest pixel using the dimmest backlight possible. Tricks like those might explain why the slowest panels on this roundup are almost exactly two frames slower than the fastest: one frame delay to shift the frame in the memory buffer while applying filters and searching for the brightest pixel, another frame delay to shift the frame out to the panel with adjusted brightness.
Many LCDs do a lot more than simply dumping signal straight from the input to the display controller.
I wish threads that got bumped by spammers would stop bouncing back into my "new updates" list every time spam gets added and removed. I must have come back to this thread with the above post as most recent more than a dozen times by now.
I wish the forum would delete "new update" notifications when the newest post in a thread is older than the notification after spam got deleted.