Sign in with
Sign up | Sign in

Measurement And Calibration Methodology: How We Test

Dell P2714T 27-Inch Touchscreen Monitor, Reviewed
By

To measure and calibrate monitors, we use an i1Pro spectrophotometer and version 5.1.2 of SpectraCal’s CalMAN software.

For patterns, we employ an AccuPel DVG-5000 video signal generator. This approach removes video cards and drivers from the signal chain, allowing the display to receive true reference patterns. Connections are made via HDMI.

The AccuPel DVG-5000 is capable of generating all types of video signals at any resolution and refresh rate up to 1920x1080 at 60 Hz. It can also display motion patterns to evaluate a monitor's video processing capabilities, with 3D patterns available in every format. This allows us to measure color and grayscale performance, crosstalk, and ghosting in 3D content via the 3D glasses.

The i1Pro is placed at the center of the screen (unless we’re measuring uniformity) and sealed against it to block out any ambient light. The Accupel pattern generator (bottom left) is controlled via USB by CalMAN, which is running on the Dell XPS laptop on the right.

Our version of CalMAN Ultimate allows me to design all of the screens and workflows to best suit the purpose at hand. To that end, we’ve created a display review workflow from scratch. This way, we can be sure and collect all the necessary data with a concise and efficient set of measurements.

The charts show us the RGB levels, gamma response, and Delta E error for every brightness point from zero to 100 percent. The table shows us the raw data for each measurement. And the area in the upper-left tells us luminance, average gamma, Delta E, and contrast ratio. The individual charts can be copied to the Windows clipboard to easily create graphics for our reviews.

Every primary and secondary color is measured at 20, 40, 60, 80, and 100 percent saturation. The color saturation level is simply the distance from the white point on the CIE chart. You can see the targets moving out from white in a straight line. The further a point is from center, the greater the saturation until you hit 100 percent at the edge of the gamut triangle. This shows us the display’s response at a cross-section of color points. Many monitors score well when only the 100 percent saturations are measured. Hitting the targets at the lower saturations is more difficult, and factors into our average Delta E value (which explains why our Delta E values are sometimes higher than those reported by other publications).

Display all 24 comments.
This thread is closed for comments
  • 5 Hide
    killerclick , January 8, 2014 4:22 AM
    Lol touchscreens on the desktop, it was a crappy idea 2 years ago and it's a crappy idea now.
  • -2 Hide
    damianrobertjones , January 8, 2014 4:30 AM
    @killerclick: That, of course, is YOUR opinion. I'd rather have the option than not have the option. Maybe we should just stop providing options... ."Having to lift your hand from the keyboard to reach out and touch your monitor definitely takes more time."So does moving your hand from the mouse back to the keyboard. As it stands I do actually prefer having touch.
  • -6 Hide
    damianrobertjones , January 8, 2014 4:30 AM
    @killerclick: That, of course, is YOUR opinion. I'd rather have the option than not have the option. Maybe we should just stop providing options... ."Having to lift your hand from the keyboard to reach out and touch your monitor definitely takes more time."So does moving your hand from the mouse back to the keyboard. As it stands I do actually prefer having touch.
  • 1 Hide
    vaughn2k , January 8, 2014 5:05 AM
    good to have this on kiosk, than have it used by designers like me.. ;) 
  • 1 Hide
    therogerwilco , January 8, 2014 6:47 AM
    Don't talk to me about desktop monitors unless they have better resolutions than 1600p.
  • 1 Hide
    InvalidError , January 8, 2014 7:21 AM
    @damian: having options may be nice but touch-screen on the desktop for everyday computing and productivity with touch as the primary input sounds like a horrible ergonomic disaster: to use a large touch screen, you need to bring it close to your waist to avoid excessive strain on your arms but putting the display there means having to hold your head at ridiculous angles to look at the screen which is going to strain your neck.So, touch on a large screen only makes sense for occasional/intermittent use.
  • 1 Hide
    killerclick , January 8, 2014 7:47 AM
    Quote:
    @killerclick: That, of course, is YOUR opinion. I'd rather have the option than not have the option. Maybe we should just stop providing options...


    I said it's a crappy idea that's not going to catch on, and I'd prefer not to have to pay extra for it or sacrifice other aspects of the display, like resolution in this case. That said, the companies can put their R&D and marketing $ wherever they want, not my money, but it's still dumb.
  • 1 Hide
    Patrick Tobin , January 8, 2014 9:35 AM
    After having used touch extensively on desktop, laptop and tablet form factors I have to say it works really well for a desktop system for quick hits and the such and getting in and out of stuff quickly in Windows 8, on a laptop it makes very little sense though. I would rather have it than not, but not at 1920x1080.
  • 1 Hide
    hannibal , January 8, 2014 10:12 AM
    The childrens that are now using iDevices and similar can not live with traditional display if there are these in the market. In the long run non touchable monitors are gonna die out. Sooner or later there are more of those touch orientated customer than we old fossilised normal screen users... Eventually we die out and so will normal monitors. For me touch based pad with screen would be ideal for controlling win8 in my desktop. It would be on the table just like my mouse, so I don't have ro rise my hand to do something...In few years there will be a lot of 4K monitors with touch interface, because big audience have to have them...
  • -1 Hide
    Patrick Tobin , January 8, 2014 10:21 AM
    After having used touch extensively on desktop, laptop and tablet form factors I have to say it works really well for a desktop system for quick hits and the such and getting in and out of stuff quickly in Windows 8, on a laptop it makes very little sense though. I would rather have it than not, but not at 1920x1080.
  • 1 Hide
    InvalidError , January 8, 2014 10:25 AM
    Quote:
    It would be on the tabel just like my mouse, so I don't have ro rise my hand to do something...

    So instead of injuring your arms from repetitive stress holding them up in front to touch the screen, you are going to get RSI, cramps or other problems in your neck for staring at a steeper down-angle for too many hours a day... or get both problems, albeit over a longer term than either extreme, if you put the touch-screen somewhere in-between.

    This is going to be 'fun' 10-20 years down the road. (As in lawsuits due to not being warned by device manufacturers that extended use of their device in a typical setup may lead to injuries.)
  • 1 Hide
    red77star , January 8, 2014 2:22 PM
    What a bunch crap they are releasing now days just to justify existence of Windows 8 which clearly is not good enough for anything. Who needs this big touch screen...nobody.
  • 1 Hide
    Stevemeister , January 8, 2014 5:03 PM
    Just what we need - kids with sticky fingers smudging up the screen
  • 2 Hide
    InvalidError , January 8, 2014 5:31 PM
    Quote:
    Just what we need - kids with sticky fingers smudging up the screen

    On the plus side, as long as it is only the glass cover getting dirty, it is much easier to clean than a keyboard or mouse.
  • 2 Hide
    rantoc , January 10, 2014 8:56 AM
    27" Touchscreen for desktops with a crappy 1080p resolution... no thx! Heck making a picture of Lego would provide smaller "pixels" =P
  • 1 Hide
    rantoc , January 10, 2014 9:01 AM
    Quote:
    The childrens that are now using iDevices and similar can not live with traditional display if there are these in the market. In the long run non touchable monitors are gonna die out. Sooner or later there are more of those touch orientated customer than we old fossilised normal screen users... Eventually we die out and so wll normal monitors.For me touch based pad with screen would be ideal for controlling win8 with my desctop. It would be on the tabel just like my mouse, so I don't have ro rise my hand to do something...In few years there will be a lot of 4K monitors with touch interface, because bid audience have to have them...
    Yeah and there will be a line to the clinic with people who have shoulder problems due to the extra stress lifting an entire arm several hrs a day rather than just a hand, i doubt the touchscreens in big format will take off without the company's making them getting sued by people who will have their life destroyed due to a poor ergonomic design!
  • 0 Hide
    radiovan , January 11, 2014 12:13 AM
    Is this the Dell "NSA edition"? WOW, this thing will be as popular as the OS it comes with.
  • 0 Hide
    game junky , January 13, 2014 6:11 AM
    Though I don't think everyone desires a touch-screen desktop monitor, I can see good applications for a touch screen - for companies using computer-based payroll platforms, a flat-panel all-in-one makes for a great kiosk. I saw one being used as a catalog browsing solution at a retailer as well and that made a lot of sense to me.Not everyone wants one, but there are places where these make sense
  • 1 Hide
    InvalidError , January 13, 2014 8:54 AM
    Quote:
    a flat-panel all-in-one makes for a great kiosk.

    Kiosks is a nice use of touch since it is pretty easy to "secure" those by simply omitting unwanted access in the UI design with the rest of the system physically locked out - touch-based kiosks have been around for a long time: the first time I have seen a touch-based terminal was in a video rental store about 15 years ago and the menu was in good old 80x25 text mode.

    Industrial touch applications are nice too since you can seal the display on the "dirty" hot side of the application and lock the rest on the "clean" cooled weatherproof side.

    For everyday computing, touch may also have its uses such as when demonstrating stuff: instead of demonstrating software or page layouts by pointing things out on the screen with fingers and then using a keyboard/mouse to activate the object or navigate pages, clickable things can be demonstrated on-screen - you already have your fingers in there to point things out anyway.
  • 1 Hide
    WyomingKnott , January 14, 2014 3:39 PM
    One of the most awesomely useful devices I ever saw was a pen-input version of this. It was used for teaching in a software testing class. It had the slides on it, and the instructor could annotate the slides in real-time and, if she wished, save the annotations for the next class. It was, of course, repeated on a projector.It inspired my lifelong desire (well, all my life since them) for the ultimate smartboard. Full-color e-paper, markers, erasers, and the ability to save the screen to a thumb drive and bring the same one (or a copy) up later, halfway across the country, and continue working on it. I've seen school smartboards, but the closest that I've seen to my perfect device requires a spare room next to the conference room for the rear-projector. A front projector would have peoples' shadows.
Display more comments