BenQ PD2720U Not reaching advertised colour gamut coverage?

Home Forums Help and Support BenQ PD2720U Not reaching advertised colour gamut coverage?

Viewing 15 posts - 16 through 30 (of 78 total)
  • Author
    Posts
  • #28242

    Vincent
    Participant
    • Offline

    It looks OK but this is not profile verification. This is how good your calibrated & profiled display is while showing sRGB images in Photoshop, that’s what profile simulation do while using custom display profile as default display profile.

    I’m confused, so what should I be doing to check contrast then?

    You did it. No issues there.
    I just said that it is not profile validation as a hint for future measuremenst reports. If you only want to check if profile matches display behavior do not use simulation profile.

    #28263

    Wire
    Participant
    • Offline

    Marcell wrote:

    If the tech can only do 93% why do they advertise it as 96%?

    I don’t know this as fact, but my guess is there’s some butt-covering in claims that are at the edge of performance, because such claims can be nice pickings for attys that thrive on class-action suits.

    There is also the distinction between a 2D (plane) gamut plot of the fat region of response and a 3D (volumetric) plot. A display can be have greater proportional coverage in one than the other. Gamut claims are like so many catalog-level spec claims. For example, if you tru to shop Dell monitors by color response, you will see the biggest swath  of their offerings:  “All these displays do rich incredible color!” You have to get to know vendor lingo and how things are marketed. For example, a Dell U2518D and a UP2516D are different class of backlioghts, the latter being WCG, the former being sRGB. If you read the promo, Dell brags about 99% sRGB coverage and HDR10 as if that’s a remarkable claim when sRGB is just industry 25-year-old baseline, and HDR pertains to next-gen UHD TV specs, which just so happen to be influencing PC gaming. There’s nothing special about Dell, every purveyors plays these sorts of verbal games, which make sense from vendor perspective. Ignorance helps sales. Knowledge is a costly frill. So along the way, you will pick up little details in the literature: for example:

    https://www.dell.com/support/kbdoc/en-us/000131468/identifying-dell-monitor-types-by-their-model-number

    U:  ultrasharp which is Dell’s original “quality” brand from back in day when just having a color LCD was exciting.

    25: screen diagonal. Lawyers have sued TV makers over minor fudges on this spec and won

    16 / 18 are the model year of introduction.

    D:  QHD resolution — don’t ask why it isn’t Q — OMG

    Now in this case, the “P” is the dope, because it stands for Professional which also implies “PremierColor and it’s the WCG offering (like HP DreamColor) for multi-media designers.

    To understand why they categorize as they do, you’ve gotta survey their catalog and regard the marketing doublespeak. And because they offer into so many markets, it’s confusing. Like why is “Medical Review” special? Because you can get the shit sued out of you of some Dr makes a bad diagnosis because he didn’t see a polyp on a CT scan. Plus that industry has many special form-factors and rules.

    So per the 2D gamut plot I posted before, in my case the “P” stands for a big gamut capability difference over the other model missing the P, and also implies add-ons like DUCCS, etc.

    All the vendors have their own versions of this stuff, and some of it is pure history. In narrow cases, a vendor may target a very particular market and become known for exceptional quality in that market.

    It sounds like you buy like me, which is I want to stay up on certain trends, I have wide-ranging general interest in styles of work (web, vid, photo, etc) and I am on a budget because this is a more of a hobby. Learning how to read between the lines on vendor offerings can help.

    Vincent bemoans the marketing gobblty-gook and the missed performance claims, as he should, be there’s really nothing special about how this gear is marketed as compared to almost everything else. Does your Tesla have a SW limit on its range for no reason other than to deprive you of thousands of $? It’s just how America works.

    As far as I know, Dell doesn;t offer a specific “Adobe RGB” display. If you get a PremierColor (Pro) you get greater than P3+Adobe. Notwithstanding a percent or two.

    #28273

    Marcel
    Participant
    • Offline

    You did it. No issues there.
    I just said that it is not profile validation as a hint for future measuremenst reports. If you only want to check if profile matches display behavior do not use simulation profile.

    Ah  I see, okay.
    Did another calibration with 2.2 gamma and did the report with simulation profile unchecked. Results look pretty similar.

    Attachments:
    You must be logged in to view attached files.
    #28275

    Marcel
    Participant
    • Offline

    Marcell wrote:

    If the tech can only do 93% why do they advertise it as 96%?

    I don’t know this as fact, but my guess is there’s some butt-covering in claims that are at the edge of performance, because such claims can be nice pickings for attys that thrive on class-action suits.

    There is also the distinction between a 2D (plane) gamut plot of the fat region of response and a 3D (volumetric) plot. A display can be have greater proportional coverage in one than the other. Gamut claims are like so many catalog-level spec claims. For example, if you tru to shop Dell monitors by color response, you will see the biggest swath  of their offerings:  “All these displays do rich incredible color!” You have to get to know vendor lingo and how things are marketed. For example, a Dell U2518D and a UP2516D are different class of backlioghts, the latter being WCG, the former being sRGB. If you read the promo, Dell brags about 99% sRGB coverage and HDR10 as if that’s a remarkable claim when sRGB is just industry 25-year-old baseline, and HDR pertains to next-gen UHD TV specs, which just so happen to be influencing PC gaming. There’s nothing special about Dell, every purveyors plays these sorts of verbal games, which make sense from vendor perspective. Ignorance helps sales. Knowledge is a costly frill. So along the way, you will pick up little details in the literature: for example:

    https://www.dell.com/support/kbdoc/en-us/000131468/identifying-dell-monitor-types-by-their-model-number

    U:  ultrasharp which is Dell’s original “quality” brand from back in day when just having a color LCD was exciting.

    25: screen diagonal. Lawyers have sued TV makers over minor fudges on this spec and won

    16 / 18 are the model year of introduction.

    D:  QHD resolution — don’t ask why it isn’t Q — OMG

    Now in this case, the “P” is the dope, because it stands for Professional which also implies “PremierColor and it’s the WCG offering (like HP DreamColor) for multi-media designers.

    To understand why they categorize as they do, you’ve gotta survey their catalog and regard the marketing doublespeak. And because they offer into so many markets, it’s confusing. Like why is “Medical Review” special? Because you can get the shit sued out of you of some Dr makes a bad diagnosis because he didn’t see a polyp on a CT scan. Plus that industry has many special form-factors and rules.

    So per the 2D gamut plot I posted before, in my case the “P” stands for a big gamut capability difference over the other model missing the P, and also implies add-ons like DUCCS, etc.

    All the vendors have their own versions of this stuff, and some of it is pure history. In narrow cases, a vendor may target a very particular market and become known for exceptional quality in that market.

    Yeah its really annoying the way they mislead. Guess they are measuring to their own version of the standard or something. Makes me feel like I got ripped off because I’m paying for 96% not 91%. A lot of cheaper monitors advertise 90% but I wonder if they are actually like 85%.

    It sounds like you buy like me, which is I want to stay up on certain trends, I have wide-ranging general interest in styles of work (web, vid, photo, etc) and I am on a budget because this is a more of a hobby. Learning how to read between the lines on vendor offerings can help.

    Yeah I like to try to keep up with tech, but I’m also looking for best bang for the buck. Some things I just can’t justify spending boatloads of money on as much as I would like to. 😛

    As far as I know, Dell doesn;t offer a specific “Adobe RGB” display. If you get a PremierColor (Pro) you get greater than P3+Adobe. Notwithstanding a percent or two.

    Just looked on dells site and the only PremiereColour that comes up for 4k 27-32 inch is $2700! Way above my budget. 😛 Hopefully in a few years when I upgrade again the tech will be cheaper.

    #28276

    Vincent
    Participant
    • Offline

    AFAIK for Dell.

    E – Office (usually) TN

    P – IPS (or close sibling) models for office = BL from Benq?

    S- gamer/multimedia models (can be good IPS, can be cheap TN… etc depending on model)

    Current U- IPS with supposed factory calibration + OSD controls for gain saturation etc. = PD series from Benq
    Former U = Current U + current UP models, same segment

    UP- Widegamut AdobeRGB models with HW calibration, Dell splitted previous U naming = PV and SW series from Benq, with SW low end.

    Regarding % in DisplayCAL/argyll that intersection value is calculated on 3d volume. Check colprof or viewgam documentation, I don’t remember

    #28284

    Wire
    Participant
    • Offline

    Dell’s monikers are documented at the link I sent a post ago… Here it is again.

    Dell Monitor Types by Model Number
    https://www.dell.com/support/kbdoc/en-us/000131468/identifying-dell-monitor-types-by-their-model-number

    UP are WCG > than Adobe+P3. Great for multimedia device.

    I’m sad they discontinued the UP16 QHD models because they are fantastic value for money and around $400 US for 25 in. In my case I got on sale for $299. At the same time the 27 in was US $379

    Marcel, I say know what you need, and buy at low-end of market and don’t fret over a few percent of coverage.

    For fun, run the 3G gamut plot and compare.

    If you are on Mac, Apple’s built-in ColorSync Utilities (Apps > Utilities) has a very easy-to-use gamut viewer with 3D visualizer that’s a great complement to ICC Profile Info. NOTE: When comparing Colorsync Utility plots the presentation is normalized to device white (RelCol) which is a bit counter intuitive.

    As to trends, my sense is that display tech is undergoing big changes right now with UHD and OLED… A sea change with lots still being worked out.

    My good luck with the UP2516D was that it’s a completely mature product in its class (multi-media displays for designers) which was sold at commodities prices. And as my eyes are terrible I don’t mind QHD 🙂

    #28285

    Wire
    Participant
    • Offline

    Vincent, on UP2516D I can confirm a 6 dE variance on white tracking from lowest brightness to highest.

    I just measured both my displays using spotread and i1dpp and CCT blue/yellow holds steady across the range. Almost all of the delta is Duv which runs from pinker (low brightness) to green (high) with a spread of ~5.5 dE’00.

    Temp stability is a couple of dE from cold to fully warmed up. So it’s instant-on and ready to go.

    #28286

    Vincent
    Participant
    • Offline

    What I wrote is Benq Dell market segment equivalence

    Regarding whitepoint drift, then bad news using DUCCS like many other users… DUCCS is not prepared to deal with that kind of poor quality HW.
    If WP goes off like in so much desperate users try to figure white xy offset in advance (because of the WP shift due to post calibration brightness correction, you can see it in DUCCS text logs). If uncalibreated grey is poor in color, calibrated grey wiill be poor quality too (bad range), DisplayCAL GPU calibration on top of that is adviced for that users, hardware CAN correct it, it’s a 1024 lut after all… it’s just that Dell did & does not care.

    If you can code you can try to upload a native gamut calibration although only with SDK up to 2.0. Newer SDK versions (3, 3.1) have lesser features. Unfortunately profesional models with HW calibration from 2013 series have not that chance… although such SDK exists for them, otherwise DUCCS could not calibrate them.

    “Dell doing dell things”

    #28287

    Wire
    Participant
    • Offline

    No need to improve because I cannot see the swing from low-to-high. Gray tracks perfectly, so it looks like white hold perfectly steady. I only know because instrument tells me. If I had a better-performing device sitting next to it, it might call attention to itself. If I were running a studio, I would arrange to fix luminance and so also not an issue. So, to me, there is simply no issue. If Dell asked me to pay double to improve the delta, I would say I will keep my money as it adds no value.

    #28288

    Wire
    Participant
    • Offline

    For all I know, Dell engineers studied perceptual response and determined that a precise Duv shift was required to keep users from seeing a drift in their own vision!

    #28289

    Vincent
    Participant
    • Offline

    That is not true. DUCCS is a fairly well documented price of trash… I mean, we have logs of all its wrong doings. We know them in better detail that then even worse piece of trash that are Palette Master Elements, True Color Pro or other counterparts.

    So if you cannot guarantee a stable WP for your displays, you cannot make such high range modifications for brightness after LUT is wrote, and DUCCS does that. They do not guess initial brightness for calibration target + a margin, calibrate then apply minor correction because of white point correction in LUT. No, they go default brightness, compute LUT, then make FULL brightness correction from default CALx brightness value.
    Also if you cannot guarantee a fairly neutral grey out of the box (in uncalibrated CALx slots) in all your displays , you cannot take 10 grey measurements (old DUCCS) or 20 (new/last DUCCS with -wrong- PFS support that IDNK if you are using). You have a HW with several 1024 entry LUT per channel, able to correct even the tiniest drift… but due to “user target” and their impatience dev guys “guess” that they do not like to wait a little, so its measure uncalibrated grey in a poor & fast way… and no, a HUGE amount of displays going out your factories need at least twice measurements to make use of that HW.
    Same for not providing proper correction for newer UPs & colorimeters.
    Or playing down in contrast below what panel can offer in first stage on a lot of models.

    Dell cannot guarantee that the initial state of all (or at least a huge amount) of their displays will meet all these assumptions, hence with a little googling you see all the mess they left behind. Same for Benq or LG: 7dE ow daylight locus aiming towards D65 (and DUCCS resulting icc profile storing that, it os not a measurement issue). Serial number verification driving out users from app because USB connection issue, etc.
    That is not a HW QC issue like uniformity (non correctable, a matter of target price & statistics). This is software, software presuming an idealized behavior that Dell cannot meet. All these issues could be corrected if Dell wanted because “it’s just software”.

    AND THE DO NOT CARE and your last message is simply a lie. Why is it a lie? because we have logs. Read them, full WriteI2C/ReadI2C operations and CIE xyY readings. DUCCS is not doing what you presume. After LUT is writen, WP is fairly on spot for almost all displays. Then they play with brightness… some are well behaved with little WP shifts, others don’t. DUCCS meeting calibration target is just chance that uncalibrated display behavior meet the highly idealized assumptions from dev team: 1 of 10? 1 of 20? 1 of 50?
    A dev team that now that Dell is more friendly to another soft provider for calibration (UP2720Q), deprives you and other owners from an updated SDK to calibrate by yourself in an independent way, or from an i1Profiler 3 equivalent (people have printers & scanners and as XR services update they do not like older/newer versions messing around).
    Also I must say that they learnt the lesson, Dell Calibration Assitant (DUCCS substitute for newer models) is now a monoblock black box without further information about what it does, so all this kind of stuff goes unnoticed (although UP2720Q QC is extremely high so assumptions have a solid basis and can be justified for that model IMHO).

    Take on it, Dell never really cared.
    But all of this is just offtopic that we may have skiped if you actually knew how DUCCS works… and you could: you have DUCCS, you have run it, so you have logs to learn how it works. It may work by chance in your display, but man…. DUCCS is not close to be ready for production with Dell QC in DUCCS compatible HW. A piece of trash, although better software than others.

    #28290

    Marcel
    Participant
    • Offline

    For fun, run the 3G gamut plot and compare.

    Where do I find that test in displaycal?

    If you are on Mac, Apple’s built-in ColorSync Utilities (Apps > Utilities) has a very easy-to-use gamut viewer with 3D visualizer that’s a great complement to ICC Profile Info. NOTE: When comparing Colorsync Utility plots the presentation is normalized to device white (RelCol) which is a bit counter intuitive.

    I’m on windows, does it have something like that?

    My good luck with the UP2516D was that it’s a completely mature product in its class (multi-media displays for designers) which was sold at commodities prices. And as my eyes are terrible I don’t mind QHD 🙂

    Specs on that monitor look pretty impressive with 100% AdobeRGB and 98% DCI-P3. What does DisplayCal say you are reaching?

    QHD would probably be better for a lot of things like gaming, or just windows in general. Everything is super tiny at 4k and DPI scaling on windows is pretty derpy as some programs seem to just ignore it for part of their gui or some things look blurry. But I use this monitor as my full screen preview monitor when video editing. Since I’m shooting 4k, editing in 4k, and exporting in 4k for a lot of projects it just makes sense to have a 4k screen, so I can see what it actually looks like at full resolution and makes it easier to see if a shot is slightly out of focus.

    • This reply was modified 6 months, 1 week ago by Marcel.
    #28292

    Wire
    Participant
    • Offline

    The gamut viewer is a companion program with DCal called ICC Profile Info. Prolly in DCal program group in Start

    The UP2516D meets spec according to DCal. See the 2D plot I attached to my first post.

    One of the two units I have was smashed in shipping. FedEx put it on a truck for delivery over 15 times before actually delivering, and these no doubt got thrown around a lot.  Dell replaced  it free, but the one they sent to replace has a firmware mis calibration of white in its “color space” preset modes, eg : sRGB, Adobe, DCI. It’s quite wrong.  I decided not to fuss about it because I never use these modes and I would use DUCCS (Dell’s i1 Profiler) to load a user-CAL slot with custom measured config if I did. It works well in all other ways. I use these two side-by-side and they are identical  caled and profiled, but there responses are slightly different according to their profiles.

    However when DUCCS gives them a personality they are effectively identical.

    I updated the firmware and later Dell removed the update from web and never replaced. At same time I found that a loaded user-CAL slot — by this I mean a personality crested by DUCCS via XRite and stored in firmware — is brightness locked to level set at time of cal. Vincent reports this is not typical. I’ve always wondered if the lock was a consequence of this ghost firmware update. I should have let it be.

    But I really don’t care because I run native mode, via a DCal alignment andMac is fully color managed.

    Again, my expectations are met because these we’re insanely inexpensive. The second display was free due to sale.

    The other unit meets Dell claims in all ways.

    If you look for one used, you’ll want to see it first hand as tinted-non-uniformity in white is the most common reason for disappointment in IPS displays. Both of mine perform as expected and I’ve had 6 Dell IPS over 15 years and they all work great. The oldest ones are still in service, but the backlight diffusers are showing slight degradation as may be expected for old plastic.

    Dell uniformity compensation meets Dell’s claim but costs a full level of contrast and locks white from OSD. It’s  not just a gimmick, but the trade-off is not worth it, and uniformity is fine without it.

    I’m super pleased ,but at this price-point buyer beware. If you are in US Dell is good about returns.

    Dell offers exceptional sales a couple times a year so worth it to check in once and a while, but I think these are discontinued as of last year…

    #28313

    Marcel
    Participant
    • Offline

    The gamut viewer is a companion program with DCal called ICC Profile Info. Prolly in DCal program group in Start

    Profile Info just brings up the page I attached to my first post?

    The UP2516D meets spec according to DCal. See the 2D plot I attached to my first post.

    Didn’t see any percents on that image just diagrams? What calibrator do you use? BenQ’s excuse to me for not reaching claimed percent is my calibrator isn’t accurate enough. (◔_◔)

    #28314

    Vincent
    Participant
    • Offline

    The gamut viewer is a companion program with DCal called ICC Profile Info. Prolly in DCal program group in Start

    Profile Info just brings up the page I attached to my first post?

    Yes

    The UP2516D meets spec according to DCal. See the 2D plot I attached to my first post.

    Didn’t see any percents on that image just diagrams?

    % are calculated by another command line application. When you profile a display, after ICC is made, a set ot other commandl ine apps are triggered to provide feedback, also you can visually preview profile like in your 1st post by clicking on a checkbox. But that displayprofile info is different from volume intersection.

    If you want to see volume intersection % of an arbitrary profile with your display profile (or another kind of profile) you need to execute a few commandline orders:
    iccgamut to compute .gam volume for each profile
    https://www.argyllcms.com/doc/iccgamut.html
    viewgam -i to compute intersection
    https://www.argyllcms.com/doc/viewgam.html

    Also fell free to request a separate app for this feature in future DisplayCAL releases, if this is not supported now.

    If you want to avoid using command line:
    Reinstall profile without redoing it, just installing it with DisplayCAL will trigger them
    Maybe running a 3D view on browser from display profile info triggers them too (depending on -i param presence), so check DisplayCAL logs when running a 3D plot.

Viewing 15 posts - 16 through 30 (of 78 total)

You must be logged in to reply to this topic.

Log in or Register

Display Calibration and Characterization powered by ArgyllCMS