July 2, 2017 at 4:00 am #43741
I don’t know if this point has been settled elsewhere, but terms like 1080p have nothing to do with resolution. The p refers to “progressive” as in progressive scan, i.e., the picture is scanned in a single sweep from top to bottom. All HD sets are something-p but all broadcast and cable TV (SFAIK) is in 1080i, which is an interlaced scan (we used to have those on CRT monitors). Half of the horizontal lines are scanned in one sweep, say lines 1 through 1079, and the even numbered lines are scanned in the second sweep. (The entire TV picture is transmitted 30 times a second; each half-scan takes one-60th of a second. The high refresh rates advertised are a fraud; the set merely duplicates the same picture until the next new one comes in 33.3 msec later. How does this improve anything?)
I saw a lot about QLED panels in earlier posts in this thread, but all seemed to be looking forward. They’re here, folks. I have a 65-inch curved screen Samsung QLED UHD TV. They are pricey as all get-out right now, but they’re already beginning to come down in price, albeit slowly. The picture is incredible, almost as good as OLEDs which are way beyond pricey. I don’t know of any QLED monitors at this time (but I could be wrong, heh heh!).
Lastly, I upgraded to a Spyder5elite+ (the upgrade just activates parts of the software that were not accessible in the plain-Jane version). It works even better. One caveat: you should calibrate your monitor in a dark room (I did mine at night this time with no lights turned on). The results are fantastic–even better than the first calibration. All pictures are now spot-on, whereas a few were still a little iffy after the first calibration.July 2, 2017 at 7:01 am #43742
Yes indeed, you’ll never see me (or rarely – call me out when I do) using terms like ‘1080p’. And sometimes I see people using terms like ‘1440p’ and ‘2K’ which really makes my blood boil. For shorthand I much prefer Full HD/FHD/WQHD etc. or simply writing the full resolution, which is more informative regardless of an individual’s level of knowledge.
The discussion on QLED earlier in this thread was primarily actual QLED, not Quantum Dot backlighting. All we have at the moment is an LED backlight enriched with Quantum Dots instead of a phospor. So QLED hasn’t really arrived. Samsung kindly adopted the term ‘QLED’ because it sounds cool and new, but the more correct term for what they use would be QD Film, QDEF or QD-LED.July 3, 2017 at 4:55 am #43748
I’m not sure I get the distinction. The QLED SUHD TV that I bought last month set me back $3800, whereas “quantum dot” sets that did not sport the “QLED” label were selling for the low thousands (i.e., $1200 for a 65-inch set). So either Samsung is pulling off a massive fraud on the public, or something else is going on here. I vote for the latter, since I was able to compare ordinary quantum dot SUHDs directly with QLED sets in a side-by-side setting, and there was all the difference in the world between the two display technologies
While it may not be QLED by the ordinary definition, it is definitely a BIG step forward in TV panel technology. Significantly, the $512 CH711 is advertised only as a quantum dot monitor, not QLED. I would expect a true (Samsung) QLED monitor to sell for about half what an OLED monitor would bring. Say around $1700 for a 30 or 32 inch panel. Monitors do not enjoy the economies of scale that TVs bring. BTW, Amazon is now selling the CH711 at $480.
I could not find any definition for QLED monitors on the Internet that differed in any stated respect with the QLED TVs now being sold by Samsung. I did find a new QLED Samsung monitor, the CHG70, which goes on sale July 7 at $700, so considerably less than I predicted above. It’s a 32-inch, 2560×1440 display with a 144 Hz refresh rate and is billed as a “gaming monitor” (I don’t give a whit about games, since I never play games with my computer–never).
One parting shot: the vaunted advantage of OLED displays in deep blacks is effectively negated by room lighting, unless you watch in the dark–which any eye doctor will tell you to never do. In the brightly-lit BestBuy store, I could not tell the difference between the blacks on the OLED and QLED sets.July 3, 2017 at 7:06 am #43750
I’d suggest reading the article I linked to on backlighting and also the OLED monitors article (last paragraph), because the distinction is made quite clear. All ‘QLED’ means at the moment, Samsung or otherwise, is the use of Quantum Dots in place of phosphors as part of an LED backlight. That is completely distinct from getting away with the backlight entirely and using the Quantum Dots as a per-pixel lighting source.
The price differences and general image quality differences are down to backlight design and various other ‘features’ of the TV. The use of local dimming on the backlight and associated HDR capabilities can certainly demand a premium. There have been price gulfs in TV technology like that for decades, it’s nothing whatsoever to do with ‘QLED’. Don’t let anybody tell you your TV isn’t giving you a lovely viewing experience, it most certainly will be. But also try to understand the difference between QLED ‘as a backlight’ and in its pure sense.July 4, 2017 at 4:04 am #43758
Yes, I did find a definition of the “pure” QLED system. It’s what I always expected them to do: Use individual LEDs as the light source for a TV (or monitor) picture. But as of now, I’m afraid that’s just a pipe dream. I believe it would be prohibitively expensive to produce such panels. . . in the foreseeable future, that is. LOL
That said, there is a definite difference in what Samsung is now calling QLED and the “original” quantum dot technology. They describe it as “a reinvented quantum dot technology with a new metal core.” And their claim of 125% sRGB gamut applies only to the QLED panels, not the previous generation of quantum dot panels they sold for the past couple of years. They emphatically state that their previous quantum dot TVs are not QLEDs. As for me, I’d say the pictures from TVs with the two versions of the technology prove their point. They are not the same. Seeing is believing.
I would still like to know who gave the “pure” QLED technology that name, and why. What does the “Q” have to do with using LEDs as the light source for each pixel on a panel? I would have called it DLED: direct LED. In this sense of the term, what does the letter Q stand for anyway? This is very confusing to us common folk. Did this come from the “QD Vision” company you mentioned in the backlighting article? If so, this begs the question: What did the “QD” mean in that company’s name, and why did they choose it?
It seems to me that Samsung has opened a real can of worms by arrogating the name of an existing type of technology (which I had never heard of) for their own purposes.July 4, 2017 at 7:12 am #43759
Yes. And in the more distant future, when ‘pure QLED’ becomes a thing, what will Samsung start calling it? QLED2? 😀July 6, 2017 at 2:39 am #43770
Heh! Your guess is as good as mine. Looks like they’d be in a good pickle when the real QLED shows up in available panels. But knowing Samsung, I’d be willing to bet they’ll weasel out of it somehow. Probably turn it to their own advantage if history is any guide.
I still want to know where the “Q” in QLED came from. In Samsung’s usage, it obviously has to do with quantum dots (albeit, in an enhanced form, but still backlit panels. If the Q was derived from QD Vision’s name, it becomes a circular argument, since the “QD” in that company’s name clearly stood for “quantum dots.” (Since they have been absorbed by Samsung, their existence is in question; hence the past tense “stood.)”
If that’s not where the “Q” in QLED came from, where did it come from and what does it mean in the context of “pure QLED” panel technology?July 6, 2017 at 3:49 am #43771
One item I forgot in my previous post: There is a contradiction in the last paragraph of the Wikipedia article referenced in the article on OLED monitors. It reads in part: “Since sunlight contains roughly equal luminosities of red, green and blue, a display needs to produce approximately equal luminosities of blue, red and green. The human eye requires blue to be about five times more luminous than green, requiring five times more power.” There is a reference for the last statement, but that article says nothing about the human eye requiring blue to be 5 times more luminous than green. If that last statement is true, and sunlight contains “approximately equal luminosities of blue, red and green,” then sunlight would appear to us as strongly yellow (or possibly chartreuse, since our eyes are more sensitive to green than to red). But sunlight looks white, so one or the other statement must be false. I think they are mixing up terminology here. I suspect that the physics of this requires that blue dots get 5 times the power of green dots in order to have equal luminosity.
As to white points, there are many of them. In the film/TV industries, the white point is 5500/5600 K. See http://www.dvxuser.com/V6/showthread.php?197321-I-thought-5600k-was-daylight-color-temperature-!
Although the color temperature of direct sunlight with clear skies and the sun at a high angle in the sky is about 5800 K, daylight is composed of direct sunlight and skylight combined. The sky is not anywhere near as bright as the sun, but it is vastly bigger. It has a color temperature of around 7500 to 8000 K. When the two are summed up – sunlight and skylight – you get the 6500 K white point that is commonly used for monitor calibration. Note, however, that this puts us out of sync with TV/film white points.July 6, 2017 at 8:27 am #43772
The ‘Q’ means ‘Quantum’ or ‘Quantum Dot’ in QLED, it’s nothing to do with branding so can and has been used interchangeably whether it’s used as part of a backlight or on a per-pixel basis. Samsung sort of muscled in there as they usually do and took it to mean the former. For now.
Wikipedia is often full of rubbish, which is what you get when anybody can edit it. The reference cited there (’30’) was in no way related to the claim made regarding ‘luminosity requirements’ for different colours. Fortunately one of my colleagues is an expert in exactly that area, and confirms that the sensitivity of the green cone cell mass in our eyes is about 5 times that of blue cone cells. With red cone cells some way between but closer to green sensitivity. Sunlight is also indeed a broad spectrum light source, with roughly equal levels of ‘blue’, ‘green’ and ‘red’. But colour perception is far more complex than simply considering where the peaks of the spectrum and our eye’s sensitivity to those peaks lies. Most of us are good at distinguishing distinct colours for narrowband light, but with broadband light the interaction between different wavelengths and how we perceive colour is quite a bit more complex. And you’re absolutely correct that perceived white points of daylight are about so much more than just the sun as a ‘single light source’. Much as colour perception on monitors is about more than just the monitor as a ‘single light source’. 😉July 7, 2017 at 3:46 am #43773
Excuse me while I wipe the egg off my face. There are no blue quantum dots in QLED-LCD displays. The blue is supplied by the backlight LEDs. The blue from the backlight LEDs also excites the green and red quantum dots.
The one thing I’m not clear about is the function of the LCD layer itself. Does it act as neutral-color variable-density “shutters” for each pixel element? And in this way allows the colors (or lack thereof) to penetrate to the human eye from the panel? In other words, the LCD layer “filters” the light from the blue backlight and (green and red) quantum dots allowing it to reach the eye in varying proportions so as to form the picture that we see?
Your friend is, of course, quite right. The so-called blue cones are much less sensitive to blue light than the so-called green cones are to green light. But the human visual processing system in the visual cortex evens out all of these differences, so we see a color scene as balanced, not skewed toward the green portion of the spectrum. (I say “so-called” because none of the cones is sensitive primarily to pure blue, green, or red light. This assignment of colors to the three types of cones is merely a convenience of labeling.)
The “opponent theory” of color vision explains why there are actually four psychological primary colors instead of three: red, green, yellow, and blue. These four colors – and only these four colors – cannot be described as combinations of any other colors. True, our monitors and TVs make yellow by displaying equal amounts of red and green light, but no human being would ever describe yellow as “greenish-red” or “reddish-green.” This fact alone proves that yellow is a psychological primary color. There is more to color than meets the eye (pun intended).
You are right about Wikipedia. You can get good material there (I’m a contributing member), but you have to be careful. I’ve corrected more than one mistake there. This caveat is one reason I went out of my way to point out the contradiction in the article mentioned in a previous post.July 7, 2017 at 6:51 am #43776
That’s correct, the LCD matrix is essentially a filter that lets through varying degrees of light of the three primary colours.July 10, 2017 at 1:32 pm #43815
Actually psychological colours have nothing to do with real RGB combo to be primary colours because light source RGB are enough to be used to create all other colours. Psychological colours are merely perception regarding we don’t clearly perceive the creation/distinction what other colours could have made the yellow. Also remember materials like physical pigments giving colour and their combinations to create other colours is different than how RGB light source is being used to create other colours. People often confuse the primary colours from pigments and from light source primary colours.
For reference image http://4.bp.blogspot.com/_rTuiEKOyJfg/TOBsC1c-pFI/AAAAAAAAAAY/ACAyi91zIRY/s1600/console-09.gifJuly 10, 2017 at 1:38 pm #43816
Any news relating to ULMB being able to work on higher than 120hz?July 10, 2017 at 1:59 pm #43817
Not currently.July 15, 2017 at 11:36 pm #43892
@intikhab: You missed my point. The human visual system converts the RGB color space into a four-color space in the visual cortex. The four colors are RGBY. Therefore, these are only psychological primaries. In ordinary color work, the primaries are RGB for sources, and CMYK for reflective light (e.g., pigments). Artists believe that these primaries are Blue, Red, and Yellow, but they aren’t. The true pigment primaries are Cyan, Magenta, and Yellow (the K is for black). These distinctions have nothing to do with the psychological primaries, which exist only within the human visual processing system – and in TVs. Check it out, and you will find that television technology converts the RGB inputs internally to a four-color space with Yellow as the fourth “primary.” We created television in our own image – literally.
You must be logged in to reply to this topic.