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Check that out...

I calibrated my 2006 Dell CFL 2407WFP next to my Dell REV03 U3014 to have identical color calibration & white point.

http://imageshack.us/a/img405/9408/im40.jpg

This is using a 10MP Sony cmos Exmor.. but the same issue, where the LED based monitor is red tinted, also happen with a high end Canon EOS 5D. just not as pronounced.

I came to do this test because if I stare at the 24" monitor for a while and look away, I feel fine. and my wall look white.
But if I stare at the U3014, when I look away, my room gets a red tint for a few seconds.

I think I might have to sell this U3014 and go with a CFL monitor instead... To bad because its sharp & crisp.


edit: to make it clear, both monitor color look identical to the human eyes, but the image sensor in cameras seem to show the LED U3014 to have no green or Blue, unlike its CFL older brother.

You sure the calibration is accurate? Have you tried a different sensor/tool?

Airmantharp wrote:

You sure the calibration is accurate? Have you tried a different sensor/tool?

I showed 6 different pictures to 3 people so far and they all tell me both monitor color calibration look near identical.
It might not be perfect calibration but both monitor seem close enough that when I move images back and forth the color look like a near perfect match.

But what I find amazing is how the two monitors, only when captured with a digital sensor, seem to have very different the white point.

BTW, I only did this test because this U3014 seem to affect my vision negatively.

The 3014 is a GB-R LED backlight. Green and Blue LEDs with a red phosphor.

It's strange that you feel the red is stronger as that should be the weaker of the three colors.

Ryu Connor wrote:

The 3014 is a GB-R LED backlight. Green and Blue LEDs with a red phosphor.

It's strange that you feel the red is stronger as that should be the weaker of the three colors.

He said the after-image looks red ("if I stare at the U3014, when I look away, my room gets a red tint for a few seconds.") Which is what you'd expect of a negative after-image of a blue-green source. LEDs actually emit in very narrow frequency ranges compared to most other light sources, so it's maybe not surprising that a camera sensor reacts to them differently from our retinas. (Digital cameras generally have a filter in them because the sensors are sensitive farther into the infrared than our eyes are, for example)

UberGerbil wrote:

He said the after-image looks red ("if I stare at the U3014, when I look away, my room gets a red tint for a few seconds.") Which is what you'd expect of a negative after-image of a blue-green source. LEDs actually emit in very narrow frequency ranges compared to most other light sources, so it's maybe not surprising that a camera sensor reacts to them differently from our retinas. (Digital cameras generally have a filter in them because the sensors are sensitive farther into the infrared than our eyes are, for example)

That's right! That's similarly tied to the reason surgeons wear green IIRC.

My mistake for missing that.

The camera sensor's peak sensitivity at particular wavelengths do not line up with the LED's peak wavelengths, thus the skew in colors your camera "sees". Your eye's rods and cones have a broader wavelength range of sensitivity so the peak of the LEDs can line up well with your eyes, thus the monitor looks fine to your eyes but not to the camera.

Strange things happen with narrow wavelength "fake" whites and perceived colors. For an example, take an object that reflects primarily between a red and green peak with a monitor set up to produce a white light. The object will appear dim if not black to your eyes compared to one illuminated by a incandescent white lamp, but the correct color.

Similar inaccuracy to trying to take a picture of a "purple to your eyes" black light which comes out blue only in a photo, not the apparent purple. The peak of the CCD sensor is in the blue, and the blue portion of the spectrum is all it can see, not the UV. It certainly cannot see any red. UV Lamps appear purple since the UV begins to fluoresce your retina and stimulates the red sensitivity along with the blue thus making it appear purple.

Out of topic perhaps, but I have some UV LEDs that look bluish-white to my eyes simply because they stimulate my rods and cones in a bad way. Shine them at something florescent, and then you realize how much light energy they are putting out, but the bluish white is dim. (255nm for those interested) http://www.s-et.com/products.html

Thanks for the feedback.

I guess I'm just not an LED kind of guy.
I will look for a solid CFL based 30" model and I will most likely sell this U3014 on ebay.

If anyone got suggestions, I'm looking for a rock solid 8bit sRGB display.

CCFL is on its way out.

The Dell 3011 might be a model you'd want to chase down before it disappears forever.

Ryu Connor wrote:

CCFL is on its way out.

The Dell 3011 might be a model you'd want to chase down before it disappears forever.

Or my HP ZR30w- like the U3011, but without the scalers and input lag!

The HP ZR30w seem to have no color calibration option, correct ? I dont think this would work for me as I need to set the white point.

Side note: I did my little PWM test.. and amazingly this LED U3014 perform much better the CCFL 2407WFP !

I guess the PWM run at 2500hz on the u3014...

Wish I could take a picture.
The test is simple if you want to try it: open a white document and wave (shake back and worth ) a pencil in front.

On the 2407WFP, I see a scattered gradient.. but on the u3014 its silky smooth.

sschaem wrote:

The HP ZR30w seem to have no color calibration option, correct ? I dont think this would work for me as I need to set the white point.

HP does have some software available, but can't your calibrator do that for you?

Airmantharp wrote:

sschaem wrote:

The HP ZR30w seem to have no color calibration option, correct ? I dont think this would work for me as I need to set the white point.

HP does have some software available, but can't your calibrator do that for you?

Do you need to hookup a USB cable to the monitor to use this software ?

sschaem wrote:

Airmantharp wrote:

sschaem wrote:

The HP ZR30w seem to have no color calibration option, correct ? I dont think this would work for me as I need to set the white point.

HP does have some software available, but can't your calibrator do that for you?

Do you need to hookup a USB cable to the monitor to use this software ?

Actually, I'm not so certain about the software- I never opened the package that came with my monitor, and I can't find anything about it on HP's site, though I'm certain that people mentioned using it for professional setups. My calibrator did a perfect job the first time, though, so I haven't looked back .

That's a pretty lusty screen, I tell you. I'm sure you've read the tftcentral.co.uk review? Dell offers some software to program the hardware LUT, but you'll need the supported colorimeter to do it.

The review also goes into a little detail about the GB-LED backlight. I dunno, I think with all the customization options for the U3014, I wouldn't even think of getting rid of it.

Airmantharp wrote:

Actually, I'm not so certain about the software- I never opened the package that came with my monitor, and I can't find anything about it on HP's site, though I'm certain that people mentioned using it for professional setups. My calibrator did a perfect job the first time, though, so I haven't looked back .

When you load this image in MSPaint

http://i.imgur.com/dUpei.png

Does the gradient look perfectly smooth ?

If it does, you will find that if you use the video card to do any changes, like gamma, contrast, brightness, the smooth gradient start to get steps.

Brightness will clip your level (black or whites), and create steps
Gamma and Contrast will also create hard steps in the gradient.

The best place to do color calibration is when the monitor process the signal, so I try to always keep color setting on the PC side to pure sRGB.

drsauced wrote:

That's a pretty lusty screen, I tell you. I'm sure you've read the tftcentral.co.uk review? Dell offers some software to program the hardware LUT, but you'll need the supported colorimeter to do it.

The review also goes into a little detail about the GB-LED backlight. I dunno, I think with all the customization options for the U3014, I wouldn't even think of getting rid of it.

Yes, thats the only way to actually configure CAL1 & CAL2. (All other mode, but one are hardcoded.)

I just expected a more from this Dell flagship monitor, and I'm not alone reading some of the other owners post...
Yea, like leakage is still a problem, even with REV03... but thankfully the horizontal stripping it gone.

Its not perfect.. but, I think I can accept its fault. (I'm not perfect myself

It seems that photo pros encounter serious problems for similar reasons:

http://en.wikipedia.org/wiki/Color_rendering_index#Film_and_video_high-CRI_LED_lighting_incompatibility

And that's with LED sources specifically designed to have a high CRI, not to be used in a wide gamut monitor. Those are two different requirements for a light source, in fact contradicting - narrow peaks in the spectrum are necessary to achive a wide gamut in a monitor, and a smooth spectrum results in a high CRI.

liquidsquid wrote:

UV Lamps appear purple since the UV begins to fluoresce your retina and stimulates the red sensitivity along with the blue thus making it appear purple.

Out of topic perhaps, but I have some UV LEDs that look bluish-white to my eyes simply because they stimulate my rods and cones in a bad way.

Yes it's off topic but interesting. Please post if you have any sources describing this kind of fluorescence. You may see some UV light (say, between 370 and 400 nm) simply because it's so powerful. Either that, or your UV LEDs emit a small amount of visible light too. Have you tried to look at them through an UV filter or through ordinary glass?

Here are more cons of this display you dont read in reviews, but can see from user feedback. and I can confirm them all.
(I have the latest REV03, so all the crap from REV01 and REV02 have been fixed)

- Heavy like leakage in the bottom corners
- its like having a haze, an opaque layer at the corner. If you move your head the haze become more or less strong.
If you look at the corner dead on, the hazer goes away. But even a 10 degree angle its back and visible. (dark images/UI)

- Color shift from slight viewing angle changes
- looking at a white pure screen, part look shifted to a very slightly blue, other very slightly red.. move head and the color effect will change.
only when looking at the screen dead on do you get perfect colors... note, HW color calibration show this problem because it always get to see the display dead on with 0% viewing angle
So all the review talking about color uniformity using HW calibration software miss the mark. This screen does have hue shift from viewing angle.
Note: its minimal, and only noticeable with low saturated, low contrast images.

- Massive ghosting, massive as in you move a window with contrasted content the color shift completely on the edges of objects. But also elements like white text on dark gray, the text will become blue.

- Exaggerated lag. its about 1 to 2 frame behind my 2007 dell IPS display... moving a window across both monitor is a weird experience. The U3014 show everything delayed.

http://hardforum.com/showthread.php?t=1754377

http://en.community.dell.com/support-fo ... 13942.aspx
https://www.dropbox.com/sh/psnmgxmdq43x ... d-Over.png


So buyer beware... the U3014 got a few things going for it, but its mainly all downsides in day to day use. This product is not suitable for graphic professional or gamers.

Positive : static , wide gamut image viewing. ... but you will need to perform your own HW calibration, as the white point of all the non editable profile are literally blue.


! and yet another one ! I just go back to my gray UI.. what do I see a ghost image of the TR web page ! Even after 5 minutes I still see the Chrome outline in my text editor.

Total piece of chocolate soft serve... How can Dell sell this for $1499 ?!

More data so other dont fall in the same trap

Dell only guaranty uniforminyt over the center 2", if this is not good enought dell recommand that you return the monitor for a refund. (Thats a rev03)
http://en.community.dell.com/support-fo ... 30635.aspx


Many people have been waiting for the REV03, since rev02 and 01 had serious panel defects
http://en.community.dell.com/support-fo ... 23740.aspx

"I ordered this monitor on 10/22 from Amazon.
i am having issues others are also having. whenever I turn on the monitor, black horizontal lines flicker on the screen for ten minutes. It is also sometime difficult to wake up the monitor from sleep or to turn it off.
I was told this was due to a manufacturer defect effecting all A01s."

The more I look, the more horror I find

sschaem wrote:

! and yet another one ! I just go back to my gray UI.. what do I see a ghost image of the TR web page ! Even after 5 minutes I still see the Chrome outline in my text editor.

Meh, my 2405 does the same thing. I figured it was just gettin' old.

Damn sschaem, you've beat the hell out of these things. I'm humbled .

If you do end up with a u3011, I, for one, would be interested in any direct comparisons regarding color accuracy and input lag you'd care to make. I don't have the u3014, and have never really done extensive color calibration, but I can say, at least, that the u3011 was much better out of the box than the 3007wfp - and had finer tuning controls to dial it in from there.

Wirko wrote:

liquidsquid wrote:

UV Lamps appear purple since the UV begins to fluoresce your retina and stimulates the red sensitivity along with the blue thus making it appear purple.

Out of topic perhaps, but I have some UV LEDs that look bluish-white to my eyes simply because they stimulate my rods and cones in a bad way.

Yes it's off topic but interesting. Please post if you have any sources describing this kind of fluorescence. You may see some UV light (say, between 370 and 400 nm) simply because it's so powerful. Either that, or your UV LEDs emit a small amount of visible light too. Have you tried to look at them through an UV filter or through ordinary glass?

Yes, ordinary glass blocks the apparent "white" very well. Silicon light pipes on the other hand barely attenuate it. It is just such a strong "point" source as compared to a UV tube like a mercury bulb that these things show up. Don't quote me on this, but I believe a 1/4W UV LED has more UV output than a similar 5W Mercury tube does at the same wavelength. All energy in the case of the LED is at one wavelength instead of multiple bands. The damn things are very cool (and expensive!) Bleaches the dyes right out of construction paper in minutes.