Beware! Display Quality on SXPS16 not on par with reviews

So the screen technology cannot be too vivid by being too bright and vivid?
What if it was a 3 million candle power red light out of an 1/8 inch bulb, yet still being pure red, then is not that just a case of too bright and hence overstaurated?

I guess I don't understand, please explain to me in simple terms how a red can be too red without perception?
Unless you factor in that it's too bright, then I don't understand.

 

Vision is the preception of photons. The color is determined by the frequency of the photons while the intensity is the # of photons. This is what I mean by exact science which can be measured by instrumensts. How your eye and brain processes this information depends on the individual to some extent.

 

Intensity is different than saturation.

Saturation is the difference of a color against its own brightness. A highly saturated stimulus is vivid and intense, while a less colorful stimulus appears more muted, closer to gray. On an LCD Panel usually the primaries and secondaries are closer to grey than on an RGB LED panel or a CRT.

But at each level of saturation the colors can be brighter or more dim. For example grey varies between black and white and each color varies between black and an extremely bright level of that color.

Increasing the saturation of a color usually involves removing the other color components or adding more of that color. For example, in order to make red more saturated, you remove both blue and green or you add even more red. The saturation of a primry color is determined by the proportion of that color versus the proportion of other colors. The higher that proportion, the purer and the more saturated that color becomes. But it doesn't have to be brighter.

Take this example:
Red: 100
Blue: 50
Green: 50

Red: 70
Blue: 35
Green: 35

The first combination is brighter but color saturation is the same in both examples!

This is why color saturation doesn't vary when you change the brightness of your screen (actually it may vary slightly when you increase the backlighting because LED's or light bulbs may have slightly different color properties at different brightness levels).

 

That sounds like what I have been saying saturation is a combination of intensity and color.

So In photoshop in a 16 bit RGB color mode I have not been able to make the red any redder than R-255,G-0,B-0. So I don't know what too red means unless it's brightness intensity, more photons hitting the eye.

Speaking strictly of saturation, are we saying the RGB in the monitor is not a case of the LED's being too bright?
Because that's what I am postulating, in the same way reds and greens made my eyes bleed when I moved to LCD from CRT.

 

Thanks for the explanation, I guess I'll have to chew on it a bit before I get it, currently I don't get it.

 

I still don't see you could ever get yellow with only red, blue and green at your disposal. I mean, it sure doesn't work with my crayons.

 

I take it your being humorous but just in case...
Colors and light operate with different laws. For instance, black is the combination of all colors, while white light is comprised of all colors but black would be the absence of light.

 

Anyone know if the Sony FW 1600 x 900 screen is any better than these Dell SXPS 16's?

 

Can anyone tell me why they just didnt stick with WHITE LEDs?

Is the panel controller sophisticated enough to manage the intensity of individual LEDs in combination with the LCD pixels to produce the right colour?

eg. if your screen is all red.. does only the red (R) LED element light up in combination with the red LCD pixel element? ... OR

is the RGB just producing white light?.. in which case, it would be simpler to just use a white LED backlight

 

doesn't explain where yellow comes from RGB.

 

The perception of color is determined by the frequency / wavelength of that color. A color is saturated when it is pure (like laser light for example) and not polluted by light that uses another wave length (e.g read is saturated when no blue or green waves hit the eye).

Brightness on the other hand is determined by the intensity of that light (for example a red laser can be lighter or burn a Bluray or cut through steel).

Having said that certain wavelengths are responsible for more bightness perception. For example the perceived brigthness of green is greater than that of either blue or green.

 

What you are describing is color dimming (where only red LED's are lit when red is to be displayed and the other LEDs are dimmed). So far only one TV exists that is capable of doing that and it is very expensive because it involves a lot of picture analysis and LED's will never be as small as a pixel (so it is an approximation).

The are 2 RGB LED TVs on the market at the moment. One from Sharp and one from Sony. The Sharp has color-dimming and is very expensive, and the Sony has only local-dimming (color channel can't be dimmed individually).

In a laptop there would need to be a more complex driver for Color-Dimming to occor in combination with the picture being displayed and graphic card manufacturs would need to work intensively with all panel manufacturers. It is not likely to happen soon.

To answer your second question, the advantage of RGB LED's over White LED's is the the light produced has a more balanced color temperature (white will be white) while White LED's may produce too much blue depending on the quality of the flurescent coating that is being used.

But to be honnest, good WLEDs are equivalent to RGB LEDs. Samsung use White LEDs in their LED TV's and the color space is the same as on the Sony.

 

Yellow comes from a combinatin of Red and Green. If you add too much blue it becomes pastel yellow (less saturated) and if you add yet more it becomes grey and eventually will then turns pastel blue.

This is why calibrators use a CIE chart to help moving each color in the right direction in terms of hue (is yellow too orange/red or too green, relative intensity of red and green) and saturation (intensity of the complementary color blue).




In this instance green is too saturated because it lacks red to it and has too much blue (which also correlates with the fact that the color temperatue is too low / the greyscale is biased toward green and blue).

This means the RGB LEDs on the Samsung Panel don't produce a balanced greyscale.

 

So is the 720p screen just as bad? Also, how does the 1080p RGB compare with a 1080p Sony FW?

 

havent tested either so cannot say for sure.

 

I made a comment in this thread about bad convergence or blurry fonts on my XPS16 RGB LED panel. Please see new thread where the issue has been resolved:
http://forum.notebookreview.com/showthread.php?t=355156

 

NotebookCheck.net's review is up, with comments regarding the screen:

http://www.notebookcheck.net/Review-Dell-Studio-XPS-16-Notebook.14431.0.html

Though I'm having a hard time understanding the English of the article . . .

 

Hi,I received my laptop today and for me the reds are unberable.Puremind can you please post your settings in ATI catalyst so that we can use them.I know you said they could not be perfected but please post whatever is the best you were able to achieve with this laptop

 

This problem is bothering me big time. I'm running W7 x64 b7048 and still don't see any difference. I've tried tons of ATI custom settings, Firefox color management, and someone elses ICC profile.

ATI colors helped with the reds, but at a brightness and black level loss and mess up.

ICC profile helped with the reds only in certain programs like firefox, picture viewer, but other programs and windows stuff like desktop, thumbnails, loading bars, open windows etc, it did not help.

ATI avivo video helped with video saturation.

If I'm not satisfied with a solution pretty soon, I'm sending it back for a full refund.

 

I was thinking of returning my xps16 for a long time due to this issue, but after compensating (by eye, not a calibrator) by adjusting colors, I've decided to keep it. The panel is great in other areas.

Worth noting is that I actually had Dell replace my panel and the new one was slightly better with regards to this issue.

This is my adjustments in Catalyst CC:



And equally important, I took the RED color down 1 notch in the Windows 7 Display Color Calibration (hit the Winkey and write "display calibration" followed by a carriage return).

 

For those who got their screen replaced. Do you know if they replaced the hinges too? I'm wondering how they are removing the panel.

 

@dysonlu

My screen was swapped with a new one, including hinges. The screen he brought was one unit, assembled with hinges and all. The tech simply disassembled the laptop, disconnected all cables and swapped the whole screen without taking the screen itself apart.

I don't know if Dell would swap the panel only on this model.

I remember when I talked with the Dell rep on the phone about having my panel replaced due to convergence error, before ending the call, he asked me: "Is there anything else - ANY ISSUE with your new laptop you don't like, before I send you a tech?"

I was surprised by this and replyed "No, not really". He said "Are you totally sure?" I then said to him "Well I've noticed a very small flaw in the fit of one of the hinges, but I am not going to complain. It is really nitpicking, but the left hinge has a minute gap compared to the right one".

Before I could say anymore, he promptly replied: "I'll order a complete screen for you then, no problem. The tech will be there tomorrow, thank you, bye!".

Nice Dell rep!

 

Thanks hjorte. This is good information.

I'm sending mine for panel replacement. Laptop hinges are a common weakness point. I hope disassembling and assembling is straightforward and that they'll do a good job.

 

Puremind, thank you for your in-depth quantitative OP. I'm a semipro photographer looking for a replacement notebook with acceptable panel quality (i.e. capable of being calibrated to something resembling a standard CIE space) for post-production on the road without having to do quite so much studio rework.

I was just about to pull the trigger on the SXPS 16 because of the great reviews and current one-day sale ... until I read this thread at the last minute. Right now, it seems like a fantastic value on paper, and I'm sure it is for non-critical applications, but I guess you get what you pay for in terms of professional usage.

So thanks for saving me from a potentially expensive mistake - your post was very much appreciated.

 

My screen does not suffer from over saturation so i guess not everyone gets it

 

I would like to see how the WLED fares by comparison.

 

You can't judge quantitative saturation or any other color parameter using your eyes (strange as that may sound to people who don't work daily with color management). I'm sure this panel looks absolutely fantastic for gaming, movies and general use, but what looks great isn't necessarily the right thing for professional use. Saturation curves are usually not a function of quality control, but of the original panel design, and so are consistent from screen to screen.

Color management isn't about making things look good, it's about making sure the screen is synchronized with a theoretical standard so that images can be matched from camera to printing press throughout the imaging workflow.

I'm not really interested in how beautiful this screen appears to reviewers. What I do wish is that it could be calibrated to CIE standards, and Puremind's post indicates that it cannot. It's disappointing, because when manufacturers start throwing terms like gamut around, there is the implicit assumption that they spent some time considering proper color management. None of this means the SXPS 16 has a bad screen - on the contrary, I'm sure it's very enjoyable to use. It does, however, mean that it's specifications are not appropriate for professional use - that's all.

 

Snowkarver,

If you want to see how Studio XPS 1640's screen compares to other laptops', Anandtech has made their own review of 1640's screen here:

http://www.anandtech.com/mobile/showdoc.aspx?i=3540&p=12

 

Thanks for the link, I had already seen it and the numbers for contrast ratio and black level both left me scratching my head until I read Puremind's OP. Both set of tests say the same thing - a high black level compresses the dynamic range (contrast ratio) of this display to average, and the delta-E (a measure of how far each color on the screen falls from the theoretical standard) is good, but not sufficient for pro use.

In actuality, I should probably be looking at the ThinkPad W700 or the HP Elitebook with Dreamcolor, which are built for this sort of work - but are also huge and costs thousands more. I was hoping that the SXPS might be a sleeper and cheaper alternative, but unfortunately, it doesn't seem to be.