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True 4K / Native 4K - Pixel Shift - Help me understand it all?

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Hey guys, I'm the first to admit my novice understanding of the video side of our business (I'm a sound guy, and honestly, love my BenQ W1070ST).

But yesterday on StereoNET we published a review of BenQ's flagship projector, they call a "4K UHD LED DLP". I'm referring to the X12000.

http://www.stereo.net.au/reviews/review-benq-x12000-4k-uhd-led-home-cinema-projector

It seems it's caused quite a stir. I have a very basic understanding of why this is not "true 4K" - but if its stamped with that, sold with that and promoted with that, are we in the wrong to call it that?

Are the manufacturers (not just BenQ) claims misleading? Are they doing all they need to do to call it and market it as 4K?

One industry member claims we are in the wrong and should remove the review from our website (which I'm not going to do). From my perspective, this is a consumer style review (not a lab review). We do not have the facilities to delve deeping into the chipsets, measurements and analysis required to discect it further than that, and we only called it what it is.

I'd love to know more about this from those far more knowledgable than I (layman's terms please).

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Technically, "Ultra High Definition" is actually a derivation of the 4K digital cinema standard. However while your local multiplex shows images in native 4096 x 2160 4K resolution, the new Ultra HD consumer format has a slightly lower resolution of 3840 X 2160.

This is one reason why some brands prefer not to use the 4K label at all, sticking with Ultra HD or UHD instead.

http://www.techradar.com/news/television/ultra-hd-everything-you-need-to-know-about-4k-tv-1324103

4K and UHD seem to have become interchangeable terms... but technically not correct.

JSmith :ninja:

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Posted (edited)

marc I cant speak about the benq and dont know their tech well enough. but I can talk about the sony and jvc approach and what epson does. sony have a native 4k sensor. jvc have a 4k native sensor. however the projectors that use them are horrendously expensive we are taking $40k plus for the JVC top line and around $75k for the sony.

the lesser jvc use 4k e-shift 4 which utilises 1080p or 2k panels and moves them ever so little to create an extra field.... and generally acknowledged to achieve about 3k in real terms.

jvc describes the tech below, and the picture probably sums up best what e-shift 4 is all about,

http://eu.jvc.com/microsite/eu/dla-x9000/feature01.html4k_image02.gif

its not something new, its a technology co developed by JVC and japans NHK engineers, that had them develop a 8k projector

http://www.pmaresearch.com/pma-blogs/jvc-announces-8k-resolution-projector-with-e-shift-technology/

sony have some lesser 4k chip projectors ... however the problem with them is their optics ... i.e. dont resolve enough that they actually dont end up side by side to the e-shift JVCs bringing anything more to the table. infact many have sold their next top tier sonys we are talking $25k jobbies to buy the $8k-$10k jvcs...

there is another factor and that is related to actually whats on disc... as it turns out not all that many films are made with greater than 4k resolution cameras... and where they are many are actually digital processed with a 2k DI (digital intermediate). so in essence there isn't any more than 2k to deliver on screen. however for films do have greater res... unfortunately a thing called MTF related to losses and the theory of nyquist comes in play and little more than 3k ever gets delivered on screen in anycase... probably why the 3k or so JVCs seem to be about as good as gets. unless spending up big on $40-$75K native 4k jvc/sonys which seem to only bring marginal gains resolution wise. 

if want to read more e.g. the best jvc e-shift 4 machines vs native jvc 4k machine can read below, though will have to do a google translate, a bit technical but the pic from it probably sums up with eshift-4 machine vs native 4k how they are in practice , 

http://www.projection-homecinema.fr/2017/04/30/test-jvc-dla-z1/

comparaison-JVC-DLA-Z1-versus-X9500.jpg  

 

Epson use a play on the e-shift however their issue is they dont employ a full bandwidth 18gbps chipset so there is no hope of full bandwidth 4k ever getting to their machines.

the other issue with all this is ... in reality 4k is beyond IMAX even. and Imax requires viewing from 1-1.5x screen heights. are people going to put in setups of greater scale in home than imax ? unlikely... and this is particularly made a mockery with typical viewing distances in home settings where sit about 3m from screens and beyond... which means would need screen larger than typical aussie ceiling heights to ever fully resolve 4k/uhd

so what benefit does uhd really bring... the biggest gains i have found is actually with WCG...ie its wider colour palette. and with HDR... they both work wonderfully together for some jaw dropping pics...and this is even with films like the shallows that are 2k in reality. and there are some gains in resolution to be seen particually  with displays capable of 3k and such ...meaning for the first time we are likely even seen 2k or beyond. as generally accepted prior to this we were only seeing about 1-1.5k.

re the benq I wouldn't get too hung up on the 4k aspect.  even if it is a e-shift thing it will likely bring some gains. can they do HDR though ? I read somewhere they couldnt... which would be greatly missing out on one aspect I would feel :)

Edited by :) al

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Thanks guys - a lot to take in but I certainly have a better understanding already.

Off to read some more :)

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3 minutes ago, al said:

re the benq I wouldn't get too hung up on the 4k aspect.  even if it is a e-shift thing it will likely bring some gains. can they do HDR though ? I read somewhere they couldnt... which would be greatly missing out on one aspect I would feel :)

Quote

Keen pundits will notice the X12000 doesn’t support High Dynamic Range (HDR). It’s important to understand that Ultra HD Premium Certification was designed for televisions. As it stands today, there is currently no standard there is no such standard set out for home projectors. BenQ have told us the following:

Quote

When there is a standard set by the CEA or similar, BenQ will certainly deliver a product to the agreed and unified standard.

 

 

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There are 3 types of 4K projectors.

1. Native 4K x 3 for RGB - Sony 300/500/1000/5000 series and subsequent generations along with the JVC Z1

These use 4096x2160 4K panels which is the format used for digital cinema.

UHD BD movies are actually 2x1920 = 3840 x 2160 = 4x the no of pixels of a 1080p panel.

The thing is until you get to the 1000 series Sony and up, the lens on the entry level 300/500 series isn't quite as resolving for the improved panel resolution. So you'll find that in many AB comparisons, the second group of "fauxK" projectors don't look too bad.

2. 4K compatible aka wobulation panels aka FauxK panels like Epson 9300/10000 or JVC X9/7/5000 series

These accept a 4K signal but use 3x1080p RGB panels and then "move" the panels diagonally across to approximate the 4x increase in pixels but in reality is closer to 2x.

3. 4K DLP projectors which use one panel.

DLP uses tiny mirrors to reflect light. And most DLP projectors use only ONE panel. But because they switch so fast, you can use the same panel for RGB.

A light wheel changes the color of the light source and does it so fast that you can get the effect of 3 panels in the time domain.

With the new 4K DLP they added an extra trick.

Instead of 1920x1080 (2K x 1K) mirrors on the old FullHD DLP the new ones are about 2K x 2K - but each mirror can reflect at 2 angles in the vertical resolution so it creates the effect of 4K by 2K when done very fast.

So in effect you get a full 4K addressable space in the time domain. If you considered a single chip DLP as a full HD RGB display, the same principle would apply to the 4K DLP.

---------

That's the basic tech.

In reality though, 4K is going to be critical of the lens so be prepared to pay more for the lens or the added resolution would be hard to discern.

Also you may find other qualities to be more easily discernible - like black levels. Or contrast level.

Or the ability to handle HDR which imho is something that makes the new UHD BD format stand out - far more than the increase in resolution per se.

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Marc they should still be supporting HDR. while there is no standard we do have HDR10 we have well established means now for some 12 months plus of setting up for them to get gains. in early days some didnt understand HDR and bypassed it for SDR. however I can tell you this much watching UHD in SDR and i describe it as such is like running a ferrari on canola oil and letting its tyres down :D  HDR and WCG are a big part of the WOW factor UHD brings to the screen.

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Posted (edited)
6 hours ago, Marc said:

(I'm a sound guy, and honestly, love my BenQ W1070ST).

I have fond memories of the 3D performance of a W1070.  Low crosstalk.  And for 24p Blu-rays the 144Hz alternation rate of the active glasses (rather than the much more common 120Hz rate) made for a very smooth 3D picture. [However, like many other DLP projectors, the black level of the W1070 and W1070ST is not as black as many would prefer.]

 

6 hours ago, Marc said:

It seems it's caused quite a stir. I have a very basic understanding of why this is not "true 4K" - but if its stamped with that, sold with that and promoted with that, are we in the wrong to call it that?

Are the manufacturers (not just BenQ) claims misleading? Are they doing all they need to do to call it and market it as 4K?

I see BenQ provide this specification for the X12000: "Native Resolution‎ 3840 x 2160 with XPR technology". ‎  (The StereoNET article explicitly states that this specification for native resolution is achieved using pixel shift technology. The article refers to pixel shift not being true 4K (by which it means not true UHD). It seems to me that the StereoNET article is not hiding the fact that the projector under review uses pixel shift, nor does it hide that the pixel shift is designed around a 3840 x 2160 pixel grid rather than the slighter larger 4K pixel grid that may be used in cinemas.)

BenQ in their website material for the X12000 provide this technical explanation:

4K UHD True 8.3 Million Pixel Performance for Perfect Pictures with Subtle Details

X12000 harnesses the advanced DLP 4K UHD DMD with 2716 x 1528 (4.15 million) micromirrors to achieve Consumer Technology Association's (CTA) 4K UHD specification, utilizing XPR fast-switching technology via dual-position precision optical actuator with state-of-the-art image processing to double the resolution, reaching 3840x2160 with 8.3 million distinct pixels for each frame, four times the resolution of Full HD 1080p. Awe-inspiring 4K UHD image quality reduces blur between pixels to deliver supreme clarity and crisply defined fine details

 

I note that actual UHD has 3840 x 2160 = 8,294,400 pixels, which rounded up becomes 8.3m pixels.

The approximation is that although the pixel shift technology creates 8.3m addressable pixels these pixels are out of alignment. There is a positional offset.  I have tried to capture that in the following two diagrams:

Conventional:

A1 A2 A3 A4 A5 A6
           
B1 B2 B3 B4 B5 B6
           

Diagonally shifted:

A1   A3   A5  
  A2   A4   A6
B1   B3   B5  
  B2   B4   B6
           

 

It is impossible to create a continuous horizontal line 1 pixel wide with the e-shift/XPR technique.

However real life video never contains such superfine detail anyway. In order to avoid moiré patterns and other aliases there needs to be a slight blurring in the capture of pixels. Also it is usual with camera sensors for the colour subpixels to be arranged in a pattern involving small offsets in location (such as a BAYER pattern). Moreover UHD discs typically use chroma subsampling (as indeed do Full HD Blu-rays but at an inferior resolution) because the human eye is less sensitive to colour detail than brightness detail, and chroma-subsampling reduces file sizes.

So we are faced with source UHD pixels that are already necessarily somewhat blurred as regards the brightness (luma) and with intentionally compromised colour (chroma). If those source pixels are then resampled for mapping to the slightly offset pixel grid of a pixel-shift projector, relatively little of the visible resolution should be lost.

On the other hand, we could expect sharp edged computer graphics generated to fit a conventional UHD pixel layout not to fare as well when resampled for a pixel-shifted grid.

I understand that the remapping technology has improved compared with early pixel shifting projectors, so latest models do give pretty close to true conventional layout UHD visible resolution for video.

________

As regards home projectors and HDR, it's my understanding that it's not so much that an HDR  standard for projectors doesn't exist. It's more that home projectors can't meet the already existing HDR standards that the latest television screens can meet. It's an impossible stretch for typical home projectors to produce the peak brightness levels achieved by HDR-certified television screens.

Edited by MLXXX

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marc doing some research into this projector they indeed have left HDR off it completely which is quite strange given epson, jvc and sony all provide. JVC from day one gave its owners specific instructions on how to setup and enjoy their projectors for HDR so am not sure why BENQ cant do the same. This should be pointed out in the review in my opinion rather than a fluff off response which is what I see the benq statement as. one thing is the contrast ratio is claimed at 50,000:1 however there is comment about its actual true native contrast is likely more in the 1500:1 realm which is likely why they have not provided HDR. The LED light source though would expect to punch out some lumens so like LCD/LED vs OLED argument you would think the light output would counter.

I also note very strangely 3D is left off... very odd as this with DLP and light output capability has always been a strength of BENQ. I understand it is the Texas instruments chip set used that is the limitation but it bears mention when the competition in the 3 other major brands also achieve 3D.

Lastly a worthy mention and an issue with DLPs is RBE Rainbow effect and something tends to effect some vs others. I myself although a fan of DLP going way back and always wanting one as my first projector some years ago now unfortunately discovered i was susceptible of it. with any DLP review it bears mention on how much better the projector is with this and whether a concern or not as can completely eliminate the projector as choice for some... or bring into consideration as purchase if something improved upon wiht every new iteration.

not nit picking the review...but I think rather than getting hung up on uhd side there are probably other aspects of the projector worthy of further exploration. 

anyways i have not experienced the projector myself, just questions it raises, have no doubt its probably still a pretty awesome thing for what it does, and no doubt as a projector as well probably like many other brands their first iterations of UHD being the new frontier it is so interesting to see where they take things :)

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Posted (edited)
3 hours ago, al said:

marc doing some research into this projector they indeed have left HDR off it completely which is quite strange given epson, jvc and sony all provide. JVC from day one gave its owners specific instructions on how to setup and enjoy their projectors for HDR so am not sure why BENQ cant do the same. This should be pointed out in the review in my opinion rather than a fluff off response which is what I see the benq statement

Yes, I felt the Benq reference to waiting for an HDR standard to emerge "for projectors", to be rather lame. 

Even if a projector can't achieve a really high peak light level it ideally should still be able to map incoming HDR levels to what the projector can achieve; i.e. a good compromise, something beyond SDR if not as dynamic as the certified HDR of an HDR flat panel display. On the other hand, the more advanced 4K players offer that type of functionality for driving non-HDR displays in a "best compromise" mode but you may need to manually enter the peak brightness capability of the projector. My cheap Samsung 4K player cannot do this, but I believe the Panasonic DMP-UB900 can.

Edited by MLXXX

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Marc as others have nailed down ; its a matter of whether you consider a small 2k size pixel chip that uses extremely fast micro mirror switching to give for all intents and purposes 4k resolution or another form of wobulation [ different from jvc's e-shift but still similar in intent ] to say its not '' true 4k "' 

There was quite the argument at avs forums about its nomenclature a while back understandably [ wobulation is also used by sim2 https://www.soundandvision.com/content/sim2-projector-advances-4k-“wobulation” ]

Quote

At last year’s CEDIA we reported on a new DLP imagining chip from Texas Instruments that offered one-half the pixels required for full 4K resolution. To produce 4K, the digital micromirrors first display half the pixels in the image, then microseconds later shift by a fraction of a pixel to show the others. While this is similar to the pixel shifting (a.k.a. wobulation) now used by JVC in most of its projectors (the new BLUEscent excepted), and by Epson in its laser model, TI argues that its micromirrors can shift far more rapidly.
Read more at https://www.soundandvision.com/content/sim2-projector-advances-4k-“wobulation”#Fml0WJrjJ6Vf7uK7.99

 

This is the texas instruments chip they use 

http://hometheaterreview.com/texas-instruments-announces-4k-uhd-chipset/

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It's all very interesting. I'm still reading :)

Thanks for the input.

/down the rabbit hole ...

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Where does the new Sony LED projector stand in this and against the Benq LED model that's been out for a few months now?

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Posted (edited)

marc if wanting another take on things, its worth checking out another review done on the projector in question. done by John Archer of Trusted reviews,

http://www.trustedreviews.com/benq-x12000-review

and while John himself says he doesnt quite understand the tech, and look being proprietary by texas instruments we might never ever know apart from the marketing mumbo jumbo companies feed us. But what he does say is,

"At this point, DLP’s approach to 4K sounds suspiciously like the pseudo-4K systems used by JVC and Epson in some of their recent high-end projectors. However, TI claims that the speed with which DLP’s mirrors can switch really does result in a genuine 4K experience. And on the evidence of the X12000, TI isn’t wrong: subjective and objective testing shows that you really are seeing 4K."
 

What he does confirm is lack of HDR on this machine. 

And rather surprisingly one other aspect ... it cant actually deliver the expanded gamut on UHD blu-ray !  what it delivers it seems it makes up, i.e. not natively from the disc ???

"To be clear, since the projector can handle only SDR video inputs, the DCI-P3 colour effect is created by the projector; it isn't native playback of DCI-P3 from any of your sources – even Ultra HD Blu-ray drives."
 

so while people might question its native 4k/uhd nature I would suggest that it cant do HDR or deliver expanded gamut on uhd discs are probably a bigger bother ! 

regardless of all that, this is what he has to say re the Picture quality,

"Any doubts over whether the X12000 can really deliver a 4K picture evaporate on setting eyes on its sumptuously detailed and crisp reproduction of Ultra HD Blu-rays such as Lucy and The Revenant. Even Sony’s excellent native 4K projectors don’t do such a pristine job of handling Ultra HD Blu-rays – so it goes without saying that there’s just no comparison between the 4K performance of the X12000 and rival ‘pseudo’ 4K projectors."

some of this I suspect is due to the crisp nature DLPs tend to natively have. 

The RBE Rainbow effect I wondered about is something he does indeed cover,

"Another big issue with the X12000 is the rainbow effect. This single-chip DLP issue sees stripes of pure red, green and blue flitting over stand-out bright parts of the picture, especially if you move your eyes around the image. Even though I don’t consider myself particularly susceptible to seeing rainbowing, I found it a fairly routine distraction on the X12000. Especially since the striping appears even over bright scenes, rather than being limited to bright elements of otherwise dark scenes, as is usually the case.

Using the projector’s low lamp output reduces the impact of rainbowing to some extent, but it doesn’t fully solve the problem. "

he does still feel a success overall though :)

"VERDICT

As a first demonstration of the 4K potential of DLP projection technology, the X12000 is a resounding success. However, in other areas there are reminders that the X12000 is simply a starting point for 4K DLP – and, as such, may have taken its spirit of experimentation a step too far."


 

Edited by :) al

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21 minutes ago, al said:

What he does confirm is lack of HDR on this machine. 

And rather surprisingly one other aspect ... it cant actually deliver the expanded gamut of UHD blu-ray 

"To be clear, since the projector can handle only SDR video inputs, the DCI-P3 colour effect is created by the projector; it isn't native playback of DCI-P3 from any of your sources – even Ultra HD Blu-ray drives."

Curious what he says about SDR and UHD Al ' according to its specs it takes 2160p 24/25/30/50/60Hz‎ no problem .  only  1 port has hdmi2.0 hdcp2.2 which is needed for uhd bluray ;) Noticed they used an older 2.0 chipset ; not 2.0a which rules out HDR as said ..

Shows how linked together wide colour gamut and HDR are . accurate colour gradients are very important when reproducing specular highlights ..

Quote

 

HDMIx 2 (HDMI 1: HDMI 2.0 & HDCP 2.2; HDMI 2: HDMI 1.4a & HDCP 1.4)

 

 

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its not a 4K projector its as simple as that

wrt the blokes who want you to "tear it all down" "burn the books" "destroy the heretic" ... ( i make that sound as hysterical as possible) because thats precisely what it is, another forum hysterical debate about shifting and the like that is not too dissimilar to one of our famous "cable debates" ... thats your call, but remember "censorship only make the stupid appear intelligent"

meh, everybody knows the audio/visual/audiophile industry is full of overmarketed/mismarketed hype ... one more wont make a difference

 

except to the fanatics :)

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Posted (edited)
26 minutes ago, mello yello said:

its not a 4K projector its as simple as that

Maybe you're being a bit tongue in cheek, my good mate mello. In any case...

It doesn't have 4Ks worth of pixels in a rectangular grid but it does have 4Ks worth of of pixels it can address in a diagonally displaced grid and if the resampling is done with that geometry in mind then it ought to come out very close to a conventional 4K grid performance when fed video.  Pulsing pixels is nothing new. Plasma panels did it (admitedly quite rapidly) and RealD 3D in public cinemas does it by way of alternating the Left and Right views at 144Hz. And most movies are still being produced at the very slow rate of 24fps...

I'd prefer the marketing to acknowledge the approximation for video more overtly and to admit that static sharp pixel boundary graphics performance will be noticeably impaired, but these things do not appear to be what marketing departments are prepared to do.

The old phrase the proof of the pudding is in the eating comes to mind. If the actual performance with good quality 4K discs is giving visual resolution almost indistinguishable from that of a true 4K projector, then perhaps the marketing approach is justifiable.

[There may be greater concern with this projector as to how if at all it can be coaxed into providing a degree of HDR performance.]

Edited by MLXXX

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sorry MLXXX im a little confused, no my understanding is that it is not a true native 4K projector but used some sort of shifting and you describe it yourself as "indistinguishable from that of a true 4K projector"

as always, happy to be corrected, and i wont go all spastic to try and prove myself right either ;-)

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@mello yello 

Well I haven't seen the performance myself but I am assuming it will be very good for video, like other late model pixel-shift projectors.

The key to the apparent paradox is that good quality 4K video has no sharp pixel boundaries. That makes it possible to resample it to a different geometrical 4K layout with very little loss of visible resolution. With a little bit of sharpening thrown in will become difficult to spot that the image has been resampled to a different geometry.

In my opinion this close approximation to true UHD performance will necessarily break down if looking at razor sharp 3840x2160 format static graphics at close range, e.g. trying to use the pixel-shift projector as a 2160p computer monitor. In that special case it would produce a fuzzy image compared to a true UHD projector.

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mate if you cant tell the difference then i dont know what the problem is

its like a 4 cylinder turbo being able to do 0-100 in 5.5 seconds next to an XR6 that can do 0-100 in 5.5 seconds, both get you there, just the badge is different

in @Marc 's case it seems its the fanatics that are worried about the badge (and the 4 cylinder turbo mob vs the V6 mob)

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Guest

Just for the record, XR6's have an I6 (Inline) motor and mine does 4.9s (with a performance tune) which is ~10% better than standard.  20% more torque too @>700nm peak.  When I was going to buy a V(8) the Holden guy told me if I wanted a >$50K car for $45K I should look at 6's...  So I did...  I bought the Ford.  His loss.  But I'm happy (this is just for the record after all, nothing to do with other posts here).

I'd agree with member-1080 too, video wise, e-shift should be a fine upgrade.  There's more to UHD though, WCG plus local-dimming on newer LCDs not to mention Atmos/DTS-X which I've noticed is pretty good compared to 5.1, given I've bought a bunch of old 3D discs from CeX at "rental" prices once I was told about them here, and they don't sound quite as good.  Sort of flat, really.

The thing is, UHD has a number of improvements (also adding that colour is encoded at 4 times higher resolution than the normal blu-ray standard).. Many people might knock each thing as a small improvement and insignificant - but I think over all, all the little things add up to something really good.

If only they would sell 4K+3D+BR packaged combos.  (Oh, and back on track, my Benq W1400 still needs the inputs changed twice [while the interpolation is turned off] before it'll play 3D discs without a tear in the image showing - so without a firmware update I'm unlikely to ever buy their products again!!  A known problem that was never fixed.)

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21 minutes ago, jasoroony said:

The thing is, UHD has a number of improvements (also adding that colour is encoded at 4 times higher resolution than the normal blu-ray standard)

Resolution is measured in lines so how is the 1080 lines of colour resolution (notional) of 4K Bluray 4 times the 540 lines of 1080 Bluray?

4k Bluray down scaled to 1080 looses no colour resolution at all, its a simple conversion from 4K with  4:2:0 colour to 1080 with 4:4:4 colour with no loss.

 

4K video NEVER has 4K visible chroma resolution (about 3K tops)  and less than 1080 colour (chroma) resolution.

 

Picture "quality" has stuff all to do with "resolution", especially with movies which are not shot with resolution in mind and are highly limited by low shutter speeds. A "quality" 1080 display with high contrast, accurate colour, accurate gamma and high fill factor has it over a second rate 4K display every time IMHO.

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Posted (edited)
9 minutes ago, Owen said:

Resolution is measured in lines so how is the 1080 lines of colour resolution (notional) of 4K Bluray 4 times the 540 lines of 1080 Bluray?

4k Bluray down scaled to 1080 looses no colour resolution at all, its a simple conversion from 4K with  4:2:0 colour to 1080 with 4:4:4 colour with no loss.

 

4K video NEVER has 4K visible chroma resolution (about 3K tops)  and less than 1080 colour (chroma) resolution.

 

Picture "quality" has stuff all to do with "resolution", especially with movies which are not shot with resolution in mind and are highly limited by low shutter speeds. A "quality" 1080 display with high contrast, accurate colour, accurate gamma and high fill factor has it over a second rate 4K display every time IMHO.

Resolution is measured as width and height, last time I looked at my PC settings mate.

Edited by Guest

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Posted (edited)

No, resolution has always been measured in lines per picture hight in the professional world, and since square pixels are used the horizontal change is inferred.

1080 video is 2K, half 4K, not one quarter which would be 1K.

The more important point is how much "resolution" do we need. For most movies and screen size to viewing distance ratios 2K is fine, which is why most cinemas still use 2K with 4:4:4 colour. More pixels add very little.

 

Edited by Owen

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4 times higher precision then - so sorry, buddy.  Sheesh.

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