LED backlighted monitors - not happy with the direction things are going!

[Rubycon]

All the new Dell monitors are LED backlighted. Notebooks too. My biggest gripe with these as I can tell immediately when they are powered up - their whites are not white. Reminds me of DLP boxes that were not calibrated correctly. Whites had a blue cast to them, sometimes with a splash of green.

Problem is software really cannot correct it. At first it may seem OK but then there's a peak somewhere else where it should not be and it's easily spotted when comparing the same image side by side on a conventional CCFL backlighted display.

I understand RGB LED backlights are superior since each channel can be controlled to get the color temperature desired but these white LED backlights are just too darned blue! RGB backlights are not likely to be found on entry level products where cost is of concern as well.

Anyone else notice this trend?

 

[Ross Ridge]

White is relative so I don't have much of a problem with it being slightly blue-ish. Your eyes will adjust to it just like the they'll adjust to a "warm" CCFL. For people who need calibrated displays, it might be an issue. Though you often hear claims of wider gamuts and stuff with LED backlit displays. If you're mixing and matching CCFL and LED displays though, that would be a real problem.

My problem with LED backlit displays are the edge lit models. The uneven brightness is just horrible. Probably the wave of the future though, it looks like they're cheaper to make than CCFL backlit displays. They also allow for thinner displays, which is a big selling point with consumers.

 

[Aristotelian]

White is relative so I don't have much of a problem with it being slightly blue-ish.

How is white a "relative" notion? What you're describing is "white & blue" not "white".

 

[jiffylube1024]

Part of the problem is the LED, part of the problem is that they're all TN panels. It's worth it for the power savings and thin-ness on notebooks IMO. On desktops, it's much more of a tough decision. For my main rig, I definitely prefer a good "VA" or "IPS" panel. For people who don't need color accuracy, a thin, low power LED is a good option.

 

[Ross Ridge]

How is white a "relative" notion? What you're describing is "white & blue" not "white".

White is relative, it's as simple as that. If you sit and stare at an LED monitor with white displayed on it for a while it'll look white. If you then immediately switch to a CCFL monitor it'll look yellow-ish or red-ish white, that is until you stare it for a while then it'll look white again. Hold a white sheet piece of paper near your monitor and depending on the paper and the lighting in your room, fluorescent, incandescent or natural, it will look off-white in comparison. Or white on your monitor will look off-white compared to it.

My monitor has three pre-calibrated colour configurations, a warm setting, a cold setting and one in between. Whites will appear slightly red-ish or blue-ish compared to the surroundings depending on which I choose, but when I'm just focused on the monitor like I am now, whites just look white regardless of the setting.

Just like digital cameras have an "auto-white balance" feature, so do your eyes (and brain).

 

[Aristotelian]

White is relative, it's as simple as that. If you sit and stare at an LED monitor with white displayed on it for a while it'll look white. If you then immediately switch to a CCFL monitor it'll look yellow-ish or red-ish white, that is until you stare it for a while then it'll look white again. Hold a white sheet piece of paper near your monitor and depending on the paper and the lighting in your room, fluorescent, incandescent or natural, it will look off-white in comparison. Or white on your monitor will look off-white compared to it.

My monitor has three pre-calibrated colour configurations, a warm setting, a cold setting and one in between. Whites will appear slightly red-ish or blue-ish compared to the surroundings depending on which I choose, but when I'm just focused on the monitor like I am now, whites just look white regardless of the setting.

Just like digital cameras have an "auto-white balance" feature, so do your eyes (and brain).

Do you have any sources for this? I use plenty of screens that can't accurately reproduce whites, and I know this because my bank statement is printed on white paper that looks white in isolation and white with respect to my monitor. As I'm writing this message to you, the message box has a yellowish tint while the radiator on my right hand side is painted with white paint.

Is the 'yellow tinted white' an instance of 'white' for you? So by 'relative' you mean I'll always find some p that is more white than q, rendering no universal for 'white' that is absolute? I'm trying to understand what you mean here, not to derail the thread.

In essence, I agree with Rubycon. There is an instantiation of 'white' and very few monitors reproduce 'white' in as pure a way as it can be seen in other objects that are white (and not off white, not cream, whatever).

 

[Ross Ridge]

Is the 'yellow tinted white' an instance of 'white' for you? So by 'relative' you mean I'll always find some p that is more white than q, rendering no universal for 'white' that is absolute? I'm trying to understand what you mean here, not to derail the thread.

Something like that. Take your bank statement. You say it's white. Now take it outside during a sunny day, does it still look white? What about under bright office flourescent lighting? Or a camp fire? Under all these conditions the light coming off the paper will have a different balance of red, green and blue intensities, just as the light shining on the paper does. Yet you'll always think it's just plain white, because your only reference is other things illuminated by the light or the light itself.

You can also compare that bank statement to other bits of white paper which might not have been bleached as much or might use ultraviolet brightners that can actually increase the amount of visible light reflected by the paper. The bits of white paper I've got around here are in various different shades of white. Easy to tell the difference between when side by side, but individually it's much harder to say which is bluer or yellower. Your eyes don't have a built-in absolute white reference to make that comparison.

So you've got CCFL and LED backlights. Both have different colour temperatures, and neither is likely to exactly match the temperature of the lighting in your room. Maybe CCFL is closer, and the white on your bank statement looks more like the white on a CCFL display. Or maybe you just prefer the relatively warm white on the CCFL to relatively cold LED light. Drastically change the lighting conditions in your room, say from incadescent to office flourescent, or the other way around, and you'll be comparing those displays to a bank statement that's now a different shade of white. You might end up thinking both are warm or both are cold compared to that same piece of paper.

In ordinary use I don't think most users of LED LCDs are really going to notice that their monitors have relatively colder whites than users of CCFL LCDs. Does the yellowish tint of your monitor's white bother you? Did you even notice it before?

I think it's really only a problem when you sit an LED monitor next a CCFL montor and try to use both at the same time. I never noticed LEDs looking blueish until I saw a pair of almost identical TVs in the store, one with LED and one with CCFL.

 

[Rubycon]

I notice it immediately - it does not need to be near another source. I'll have someone with a photospectrometer compare backlights. Both sources have their pros and cons but white LEDs can be purchased in varying color temperatures and efficacy.

 

[somethingsketchy]

Are you able to adjust the color temperature through the Nvidia/AMD video card properties? Depending on the video card, you can manually adjust the temperature, so it'll appear less blue and more of a natural white.

Might be a solution depending on what the photospectometer reveals

 

[Rubycon]

Are you able to adjust the color temperature through the Nvidia/AMD video card properties? Depending on the video card, you can manually adjust the temperature, so it'll appear less blue and more of a natural white.

Might be a solution depending on what the photospectometer reveals

Yes I can however the way LCD displays work it's hard to get something that's missing with the spectral deficiency present from the backlighting.

Without a doubt RGB LED backlighting is the way to go providing the RGB channels are independently adjustable.

 

[Throckmorton]

Considering how cheap R, G, and B LEDs are, why aren't they more common??

 

[gorobei]

white(blue with yellow phosphor) is cheaper and easier. plus edge lit means "thin" = sexy airbooky attribute.

by the time true local dimming rgb led backlighting ever approaches affordable, some other tech will render it obsolete (oled,sed,etc).

 

[LiuKangBakinPie]

only difference is their source of light, which is at the back of the screen. The LCD TV uses fluorescent lamps, and the LED TV uses LED (Light Emitting Diodes). both make use of liquid crystal display technology.

 

[PottedMeat]

Considering how cheap R, G, and B LEDs are, why aren't they more common??

it's probably a tad cheaper to use just white leds. order a massive amount of white leds (cheapest ) or 3 large orders of reds, greens, blues, or single LEDs ( a little more $ ) with a red, green, and blue die ( probably the most expensive ).

additional programming ( yeah not much though ) to include a 3 channel pwm controller, supply 3 different voltages ( or space for 3 different resistors for each LED ).

 

[Rubycon]

it's probably a tad cheaper to use just white leds. order a massive amount of white leds (cheapest ) or 3 large orders of reds, greens, blues, or single LEDs ( a little more $ ) with a red, green, and blue die ( probably the most expensive ).

additional programming ( yeah not much though ) to include a 3 channel pwm controller, supply 3 different voltages ( or space for 3 different resistors for each LED ).

Simplicity will prevail in a market with razor thin profit margins.
More expensive models will definitely have RGB backlights, however.
They'd have to. Colors look crazy otherwise.

It's like comparing a 65CRI CW FL lamp to a 96CRI triphosphor full spectrum lamp.

 

[sandorski]

My LED backlit monitor seems to display White properly. I have heard of criticisms of Tint with certain Monitors, but not others. Perhaps your Dells are amongst those which Tint?

 

[eplebnista]

My HP G62 laptop's 15.6" display and ASUS 19" desktop monitor are both LED backlit and whites appear to be displayed just fine on both of them, as well as all other colors too.

 

[wuliheron]

LED back lighting isn't just sexier because its thinner, it can make a monitor last twice as long and use 1/3 less energy. Since the only real advantage of LCD monitors is their low price I think its safe to LED back lighting is here to stay. If accurate colors mean that much to you then an IPS monitor is the way to go.

 

[corkyg]

In addition, brightness setting will have an effect on "whiteness."

 

[Rubycon]

In addition, brightness setting will have an effect on "whiteness."

Yes if the LED source is a single chipped emitter. True RGB displays have tint controlled throughout the operating range via a photospectrometric sensor. Again, expensive and not found on cheap Chinese made Dell junk that's included with Inspiron stuff.

An IPS panel lighted by such a backlight would still have a blue cast. Remember if the source light is spectrally tilted it's difficult or nearly impossible to adjust the panel to compensate for it. Basically colors just look crazy. Things that are red look orange, for example.

 

[Throckmorton]

Yes if the LED source is a single chipped emitter. True RGB displays have tint controlled throughout the operating range via a photospectrometric sensor. Again, expensive and not found on cheap Chinese made Dell junk that's included with Inspiron stuff.

An IPS panel lighted by such a backlight would still have a blue cast. Remember if the source light is spectrally tilted it's difficult or nearly impossible to adjust the panel to compensate for it. Basically colors just look crazy. Things that are red look orange, for example.

I believe the color of a RGBLED screen is adjusted by changing the brightness of each color LED, not by changing the signals the pixels receive.

 

[bunnyfubbles]

yeah, I wasn't surprised that Dell chose to stick with fluorescent lighting on the U2711/U3011

 

[Cerb]

I notice it immediately - it does not need to be near another source. I'll have someone with a photospectrometer compare backlights. Both sources have their pros and cons but white LEDs can be purchased in varying color temperatures and efficacy.

White LEDs will almost all suck for backlights. The only ones that might be OK not are not cheap (Nichia's high-CRI, costing dollars each in qty). Currently, only Nichia has them with both moderate (5k+) color temps and good CRIs, and the color temp cannot be adjusted properly.

RGB, with adjustable brightness curves per color, is the only way to go (even better: add amber), even if not locally dimmable (if getting a typical TN display, why go to the trouble, v. uneven optics, which people are used to on such monitors, anyway?).

 

[Rifter]

Some LED backlights are bad some are good, its as simple as that.

My acer laptop has LED backlights and is actually a very good screen for color's, no tint at all and very crisp and clear i was actually very surprised at its quality for a low end unit.

My second monitor at work on the other hand is a LED backlit LG and has a VERY noticable blue tint that no amount of screwing with setting can help and I WANT IT TO DIE A SLOW AND PAINFUL DEATH.

 

[Rubycon]

I believe the color of a RGBLED screen is adjusted by changing the brightness of each color LED, not by changing the signals the pixels receive.

Yes if the backlight is specified as RGB LED it has discrete (and adjustable) LEDs for each RGB channels. Just having a single spectrally biased backlight and trying to adjust RGB levels with software, for example; often leads to screaming complaints of wild looking colors that cannot be corrected with anything short of a .45ACP through the middle!

Dell stuck with CCFL for their flagship models to keep them affordable. IPS panels are costly as it is.