Jump to content

Sign in to follow this  
Owen

"True 4K" Discussion

Recommended Posts

On 26/06/2019 at 4:42 PM, Matt_Walker said:

Yep - its True 4K but uses a mirror to achieve this.

Cut the marketing talk mate, the Benq is  a pixel shifter so its NOT "True 4K".

Texas Instruments, who make the imaging system call it Expanded Pixel resolution. Its just like the E -Shift systems used by JVC and Epson.

 

The real issue is does it matter?  

Remember, there are no 4K visible resolution movies. Any image captured from the real world with a camera, any camera, and encoded to a 4K video format is limited to at best 3K luma resolution and 1.5k chroma resolution. Therefore moves don't need a "True 4K" display device.

Share this post


Link to post
Share on other sites
9 minutes ago, Owen said:

Cut the marketing talk mate, the Benq is  a pixel shifter so its NOT "True 4K".

Texas Instruments, who make the imaging system call it Expanded Pixel resolution. Its just like the E -Shift systems used by JVC and Epson.

 

The real issue is does it matter?  

Remember, there are no 4K visible resolution movies. Any image captured from the real world with a camera, any camera, and encoded to a 4K video format is limited to at best 3K luma resolution and 1.5k chroma resolution. Therefore moves don't need a "True 4K" display device.

Sorry Owen - True4K is not marketing talk - this is what the CES set as any display that can produce 8.3 Million pixels at any given point in time on a screen.  If you dont like the term they use take it up with them, not BenQ.  This is what the industry tells us correct.

 

It doesnt matter how we get there (Native or with a mirror) we have 8.3 Million, individually addressable pixels on the screen - that makes us True4K according to the CES standard.

 

Does it matter - of course it does.

 

If you buy something enhanced you are getting 2 x 1080P at best. 4.1 million pixels on the screen does not make 4K - not even Enhanced 4K - its 2K at best...

 

Does it matter between "native 4K and True4K" - according to your argument it does not ... and it real life it does not.

 

 

Share this post


Link to post
Share on other sites
1 hour ago, Matt_Walker said:

It doesnt matter how we get there (Native or with a mirror) we have 8.3 Million, individually addressable pixels on the screen - that makes us True4K according to the CES standard.

To be described as "TRUE" 4K the layout of the pixels must exactly match the domestic "4K" standard of 3840x2160 for 1:1 pixel mapping. The Texas Instruments system does not do that so the image must be scaled to fit the non standard pixel grid.

On top of that, the shift system moves the pixels diagonally half a pixel and projects the second set of "shifted" pixels overlapping the first set. Each shifted pixel overlaps the corners of 4 of the first set of pixels as there is no space to put them without doing this.

 

1017dlp4k.shift.jpg

 

A "True" 4K projector does not have this pixel overlap, nor does it require any scaling to display a "True" 4K image. So no, the Benq is NOT "TRUE" 4K and to describe it as that is deceptive marketing.

 

True 4K is only relevant to PC text, graphics and test patterns, 4K movies are ALL low pass filtered and have no detail at the pixel level, therefore "true" 4K is not important for movies.

 

High contact, on the other hand is vital to image quality, much more so than pixels, and these so called 4K DLP projectors provide very poor contrast, worse than the 1080 DLP's they are designed to replace, and vastly inferior to the LCoS competition.

 

Edited by Owen

Share this post


Link to post
Share on other sites
To be described as "TRUE" 4K the layout of the pixels must exactly match the domestic "4K" standard of 3840x2160 for 1:1 pixel mapping. The Texas Instruments system does not do that so the image must be scaled to fit the non standard pixel grid.
On top of that, the shift system moves the pixels diagonally half a pixel and projects the second set of "shifted" pixels overlapping the first set. Each shifted pixel overlaps the corners of 4 of the first set of pixels as there is no space to put them without doing this.
 
1017dlp4k.shift.jpg&key=922f0c9327b7519c6af65a323fdc9409cfc06caf7914178069083ce004362056
 
A "True" 4K projector does not have this pixel overlap, nor does it require any scaling to display a "True" 4K image. So no, the Benq is NOT "TRUE" 4K and to describe it as that is deceptive marketing.
 
True 4K is only relevant to PC text, graphics and test patterns, 4K movies are ALL low pass filtered and have no detail at the pixel level, therefore "true" 4K is not important for movies.
 
High contact, on the other hand is vital to image quality, much more so than pixels, and these so called 4K DLP projectors provide very poor contrast, worse than the 1080 DLP's they are designed to replace, and vastly inferior to the LCoS competition.
 
That's the old tech mate. It shifts 3 more times in total in a clockwise direction to give full 4k individually accessible pixels318fe846dff547351da7fca599d2f9d3.jpg

Share this post


Link to post
Share on other sites


The pixels still overlap mate, and each pixel is around 4 times larger than it should be so no TRUE 4K. 

Share this post


Link to post
Share on other sites
11 hours ago, Owen said:

The pixels still overlap mate, and each pixel is around 4 times larger than it should be so no TRUE 4K. 

My understanding, and video is certainly not my specialty I admit, but this is still "True 4K" as the term has been specified Owen. Is it Native 4K? No

Unfortunately all this does of course is confuse/trick consumers. Would 99% of the population be impressed and content with 'True 4K' though? - Yes.

Share this post


Link to post
Share on other sites

4K numpty question here.

 

Does this shifting also apply to 4K panels or just PJs?

Share this post


Link to post
Share on other sites
3 minutes ago, joz said:

4K numpty question here.

 

Does this shifting also apply to 4K panels or just PJs?

I was thinking the same question Joz ......

Share this post


Link to post
Share on other sites


7 minutes ago, joz said:

4K numpty question here.

 

Does this shifting also apply to 4K panels or just PJs?

just projectors... the ones that i know that are "shifties" :D jvc xx00 series and prior, epson 9X00, benq and optoma.

 

panels as in tellies have a fixed resolution and all i know off are 4k or 8k....not that likely see it given the typical distance tellies are usually watched at.

 

none of the shifting technology are clearly native as  they use a 1080p panel...though does it matter ? generally get about 3k there about is what they achieve ie beyond 2k ... which many will argue is about what there is in source anyways.... I myself run a shifter.... its a good enough a compromise amongst all other compromises there tend to be in these things without spending a ton of money for native 4k machine.

 

resolution is only one element that makes a good picture.... 4k is beyond imax(original)... so unless setting up a beyond IMAX scaled setup to fully resolve (as imax themselves have had to do)... i wouldnt get too hung up on that aspect :) .

 

ps if you really want to get into things imax will do you a twin 4k private setup in home, dont now if there are any in the neighbourhood... :D 

 

http://www.imaxprivatetheatre.com/en/index.aspx 

Share this post


Link to post
Share on other sites

I know lenses have been discussed here many times, but that's the last piece of the puzzle before the light beam leaves the unit to go onto your screen. Even an average quality lens often can't display what's coming out the projector properly. 

 

If your new 4K TV exhibited such faults it would be returned. The idea of projectors is to have a larger image, as good in quality as TV or better again,  not worse. Just because it's bigger, doesn't mean we should settle for crap glass. 

 

9400 and 5700. Ignore the colour they weren't calibrated at that point. Menu sharpness set at default for both.

 

6060_5550.thumb.jpg.0008a583f5da29ecbb278ec7bfc27aaf.jpg

 

 

 

Share this post


Link to post
Share on other sites
3 hours ago, Marc said:

My understanding, and video is certainly not my specialty I admit, but this is still "True 4K" as the term has been specified Owen. Is it Native 4K? No

Unfortunately all this does of course is confuse/trick consumers. Would 99% of the population be impressed and content with 'True 4K' though? - Yes.

There probably shouldn't even be a term called 'True 4K'. There is native 4K and native 2K and native 2K with pixel shifting.

Epson called it 4K enhancement, JVC called it E-shift 4K and BenQ call it True 4K

 

I don't even know where the term came from?

 

What's really true, is 2K was just perfect how it was. True because I don't remember anyone ever complaining about the image clarity coming out of these projectors over the past decade.

 

4K was pushed down our throats and it only took one company to do it and the rest were forced to follow.

Share this post


Link to post
Share on other sites
17 minutes ago, oztheatre said:

What's really true, is 2K was just perfect how it was. True because I don't remember anyone ever complaining about the image clarity coming out of these projectors over the past decade.

 

4K was pushed down our throats and it only took one company to do it and the rest were forced to follow.

see the image you posted above.... is from oblivion 4k uhd ? is it ? as  source material

 

if check its technical specs....

https://www.imdb.com/title/tt1483013/technical?ref_=tt_dt_spec

 

Cinematographic Process  Digital Intermediate (2K) (master format) 
F65 RAW (4K) (source format) 
Redcode RAW (5K) (source format)

 

 

as turns out the movie itself had a 2k digital intermediate (mastering).... given source of 4k/5k its going to be a reasonable high mtf 2k source but 2k none the less.... :D 

 

what we can experience with 4k uhd and it is not to be underestimated is for the first time likely high mtf 2k :) or beyond that where possible... eg 3-3.5k with material that has a 4k DI (rare)

 

but none the less it is likely for hte first time we are expereincing. because from 2k source material prior to this due to mtf losses we were probably only exprineceing 1-1.5k :)

 

so certainly we are getting benefit with the beyond 2k machines....

 

but often it is with 2k source material ... rather than 4k :D 

Share this post


Link to post
Share on other sites


39 minutes ago, betty boop said:

see the image you posted above.... is from oblivion 4k uhd ? is it ? as  source material

 

if check its technical specs....

https://www.imdb.com/title/tt1483013/technical?ref_=tt_dt_spec

 

Cinematographic Process  Digital Intermediate (2K) (master format) 
F65 RAW (4K) (source format) 
Redcode RAW (5K) (source format)

 

 

as turns out the movie itself had a 2k digital intermediate (mastering).... given source of 4k/5k its going to be a reasonable high mtf 2k source but 2k none the less.... :D 

 

what we can experience with 4k uhd and it is not to be underestimated is for the first time likely high mtf 2k :) or beyond that where possible... eg 3-3.5k with material that has a 4k DI (rare)

 

but none the less it is likely for hte first time we are expereincing. because from 2k source material prior to this due to mtf losses we were probably only exprineceing 1-1.5k :)

 

so certainly we are getting benefit with the beyond 2k machines....

 

but often it is with 2k source material ... rather than 4k :D 

That's the blu ray version Al, the 4K version is crap, full of noise. 

Share this post


Link to post
Share on other sites
36 minutes ago, oztheatre said:

That's the blu ray version Al, the 4K version is crap, full of noise. 

even more the point :D 

 

not sure re noise. its a pretty pristine uhd, but detail isnt a step up much from the blu-ray, definite benefit with regards dynamics and colour though :)

 

some good reviews on the uhd, never seen or read anything re noise, but all call out the 2k DI which was an unfortunate aspect limiting the ultimate resolution from the film... ie it cant ever be true 4k in itself .... as we are talking in this thread here :) 

 

however it is fantastic source material regardless in both audio video... id certainly use it to showcase and have done :) I have both the 4k uhd and blu-ray

 

https://www.avforums.com/review/Oblivion-4k-Ultra-HD-Blu-ray-Review.12934

 

https://www.thedigitalbits.com/item/oblivion-uhd-bd

 

https://www.blu-ray.com/movies/Oblivion-4K-Blu-ray/156371/

Share this post


Link to post
Share on other sites

Ok, I'll make it simple guys. A "TRUE" 4K - native 4K (call it what you will) projector can resolve a 4K resolution test pattern.  None of the projectors using a shift system can do that, all they will display at 4K is a grey blur in stead of  alternating black and white lines.

 

Sony 4K projectors don't resolve the 4K test pattern either because they use so called "convergence" correction by default and the user can't turn it off. There is a service menu fix for this but it may void warranty if the user plays around in there. Have the dealer do it.

 

The "TRUE" 4K JVC's do resolve the 4K test patterns because the convergence correction system is under full user control and can (must) be turned off to avid resolution loss.

 

 

How can a projector that cannot resolve 4K be called a "True" 4K projector? If that's not deceptive marketing what the hell is?

 

 

 

As I said before, the very best 4K video is limited to 3K (weakly resolved with 30% MTF or less) for luma (the grey scale image) and only 1.5K for chroma (the colour overlay) due to 4:2:0 colour sub sampling.

A 2K (1080) display can FULLY resolve all the chroma  (colour) detail in the very best 4K video with ease.

 

MTF is a measure of image contrast at any specified spatial frequency. 30% MTF at 3K means that there is a 70% loss of contrast to details at a spatial frequency equal to 3K. Thats very poor as the human eye requires high contrast to resolve fine detail and almost all fine detail in real world scenes is of low contrast to begin with. If the detail in the original scene had only 30% contrast, which is typical, and we display it with 30% MTF we have 30% of 30% which is 10%. 10% MTF is absolutely useless and detail with such low contrast will not be visible. This is why the spatial frequency at which 30% MTF occures is considered the resolution limit of cameras, and that's being rather generous IMHO as only very high contrast details have any hope of being visible in the final on screen image.

 

13 hours ago, oztheatre said:

What's really true, is 2K was just perfect how it was. True because I don't remember anyone ever complaining about the image clarity coming out of these projectors over the past decade.

 

4K was pushed down our throats and it only took one company to do it and the rest were forced to follow.

Exactly, properly processed and displayed 1080 Bluray looks great and viewers will not know its not 4K unless there is a side by side comparison. Any difference that subtle isn't worth much in my book.

The differences people will be ware of when viewing 1080 and 4K versions of a particular movie on a True or E-Shift 4K projector have stuff all to do with resolution. The biggest difference by far is gamma followed by colour calibration, both of which have a VERY significant effect on the image we see. When we equalise the brightness, gamma and colour calibration between 1080 and 4K movies the visible "differences" magically disappear and you won't know which you are viewing.

 

14 hours ago, oztheatre said:

9400 and 5700. Ignore the colour they weren't calibrated at that point. Menu sharpness set at default for both

I am very reluctant to use photos to make any judgment but the gamma of the left and right side images is so different that comparisons are difficult. The left side image looks like it has undergone some very primitive image enhancement and looks ugly, its sure doesn't look like a lens difference.

 

Just because the sharpness setting in the user menus are the same (default) does mean anything, whats doing on in the background can be VERY different and sharpening off does NOT means it is off.

Sony has long used significant sharpening even when it shows that its off in the user menu as a marketing advantage, its cheating but is sure sucks consumers in.

 

 

Share this post


Link to post
Share on other sites

Hi everyone.

If i have a great 1080p projector Being the Panasonic AE8000U one, is there any point moving up to the Epson TW9400? Is it going to be slightly better or, night and day? I'm itching for 4k, but true 4k is to darn expensive atm.

Would i best investing in a new lamp and calibration? My lamps on 3150hrs. Thou still pretty bright.

Cheers

Share this post


Link to post
Share on other sites


10 hours ago, Perth.hifi said:

Hi everyone.

If i have a great 1080p projector Being the Panasonic AE8000U one, is there any point moving up to the Epson TW9400? Is it going to be slightly better or, night and day? I'm itching for 4k, but true 4k is to darn expensive atm.

Would i best investing in a new lamp and calibration? My lamps on 3150hrs. Thou still pretty bright.

Cheers
 

The TW9400 would be an upgrade, not really night and day, but quite noticeable. The AE8000 used the same light engine as contemporary Epsons, but used a stupid softening filter to reduce "screen door effect" from the pixel gaps in the LCD panels. IMO you're probably best waiting for Epson to go 4K - this should finally bring some price competition to the 4K projector market, albeit priced higher than the TW9400.

Share this post


Link to post
Share on other sites

Any idea if this will be a 2020 release?

So no point getting a new 4k player such as a parasonic ub420 or ub820? Amy picture difference, compared to my oppo105?

If so, would be happy to sell my oppo105? For a reasonable price.

Cheers

Share this post


Link to post
Share on other sites
3 hours ago, Perth.hifi said:

Any idea if this will be a 2020 release?

So no point getting a new 4k player such as a parasonic ub420 or ub820? Amy picture difference, compared to my oppo105?

If so, would be happy to sell my oppo105? For a reasonable price.

Cheers

 

Epson seem to be playing their cards close to their chests, so not sure if they'll go 4K next year. With the softening filter on the AE8000 I wouldn't expect to see much difference with a UB420/820, even if down-rezing a UHD disc.

Share this post


Link to post
Share on other sites
 

Epson seem to be playing their cards close to their chests, so not sure if they'll go 4K next year. With the softening filter on the AE8000 I wouldn't expect to see much difference with a UB420/820, even if down-rezing a UHD disc.

Cheers. Sounds like I'm best to maybe just invest in a new lamp (3100hrs, thou i believe 3800hrs is when it's recommended to replace) and maybe a basic calibration...

 

Might need some glasses to. Hahaha. My eyes are not what they used to be.

 

Any recommendations for lamps? Every site i look up. Seems to only offer 3 months warranty...

 

Share this post


Link to post
Share on other sites
24 minutes ago, Perth.hifi said:

Cheers. Sounds like I'm best to maybe just invest in a new lamp (3100hrs, thou i believe 3800hrs is when it's recommended to replace) and maybe a basic calibration...

 

Might need some glasses to. Hahaha. My eyes are not what they used to be.

 

Any recommendations for lamps? Every site i look up. Seems to only offer 3 months warranty...

 

I wouldn't be rushing out for a new lamp unless needed. 3 months warranty is typical.

 

The hardest part about replacement lamps is working out if you're getting a genuine lamp, not a cheap knock-off.  This crowd seem to one of the few that give a choice between genuine and alternatives. It's bizarre that the AE8000 is an example where the genuine lamp is cheaper than their knock-off.

Share this post


Link to post
Share on other sites
On 15/07/2019 at 6:57 PM, jamiefor05 said:

That's the old tech mate. It shifts 3 more times in total in a clockwise direction to give full 4k individually accessible pixels318fe846dff547351da7fca599d2f9d3.jpg

I've looked at several reviews of the BenQ W5700 but none of them includes a close up of a 4K test pattern. Has anyone else spotted such a test pattern, with the alternating black and white lines 1 pixel wide actually visible?

 

Theoretically, if the pixel size were kept small, this method would give the equivalent of true 3840x2160, on a time-multiplexed basis. 

 

Edit:

I've now found such a review for the BenQ W2700. It's at https://7review.com/benq-w2700-review/ :-

 

Performance

The first thing I did after connecting up the projector was run my standard Ultra-HD resolution test pattern. I’m pleased to report that the projector resolved the pixel-wide-or- tall lines so that they could be individually discerned (see image opposite). To be clear, they are a little smudged, not as cleanly etched as they are on an Ultra-HD TV. I reckon that could be achieved with a design change, such that the mirrors on the DMD and the spaces between them were of similar dimensions.

That would eliminate the remaining partial overlap between the shifted pixels. But that would also mean considerably reduced brightness since there’d be a markedly smaller reflective surface. Anyway, while imperfect, the line separation was the best I’ve yet seen from this breed of XPR DLP projectors.

BenQ-W2700-Review-4.jpg

▲ Close-up detail of the UHD test pattern delivered as video and captured photographically. The individual lines of pixels visible are a single pixel wide with a single pixel separation, showing that full 4K is delivered accurately.

Edited by MLXXX

Share this post


Link to post
Share on other sites

Not sure what everyone else is looking at, but I can't see pixels, the left side is green mush, red about the same and right side has some separation between the lines. 

 

At the end of the day, you can't get top end performance from a budget price.. logic wins out there. My 2700 had the worst lens I've ever seen (and the 970LK had the best one I've ever seen but 15K vs 2.4K price difference, so, point proven), the CA was that bad. Maybe in Australia we get all the defective ones that the rest of the world wont accept.. bit like us convicts ha.  Point is, no 4K quality lens = no 4k picture. A 1080P projector with a good lens will destroy any 4k projector with a cheaper quality lens.

 

If I had a say in what JVC did for example, I'd go back in time 3-4 years and re launch the 5500/7500./9500 series at a more competitive price point, they'd own the market. (3999, 5999 and 7999 for example) You'd never need anything else, period. But they're all pressing ahead trying to out do each other with 'native 4k' and 'true 4k' trying to wow everyone (and failing mostly) whilst forgetting about the basics like good optics, better image processing and better remotes.

 

Couriers aren't helping them either, but the cheapest couriers always win out and they're normally the roughest which makes the manufacturers look bad, so why do it?

20190508_101919.jpg

Share this post


Link to post
Share on other sites
On 05/08/2019 at 8:58 AM, oztheatre said:

Not sure what everyone else is looking at, but I can't see pixels, the left side is green mush, red about the same and right side has some separation between the lines. 

 

At the end of the day, you can't get top end performance from a budget price.. logic wins out there. My 2700 had the worst lens I've ever seen (and the 970LK had the best one I've ever seen but 15K vs 2.4K price difference, so, point proven), the CA was that bad.

I've seen a lot of posts mention chromatic aberration in relation to the W2700. 

 

I'm still trying to find confirmation by way of a clear photograph of a UHD test image that advanced ("4 times clockwise") pixel shifting that in theory should work so as to give true 4K resolution is in fact delivering that.  Why this really basic and obvious test doesn't seem to appear in user threads,  or in most formal reviews, escapes me. I've found a review in French that includes a glowing account of the resolution achieved but the image used to show that is not all that clear.  Here is the Google Translation version of the relevant part of the review:-

 

Sharpness / sharpness:

The purchaser of a 4K projector looks for image accuracy and gain in definition. These improvements can not be obtained if an effort is not made on the quality of the optics. This point, BenQ engineers have integrated well and offer for years on their models all-glass blocks.

BenQ W2700 test BenQ W2700 4K 2 Sharpness Chart

The W2700 is no exception to this rule and, despite its 4K simulation process, my Ultra High Definition pattern can not make the difference with the rendering of a native 4K projector like the Sony VW270 or the JVC N5 . Better still, I find that the DLP gives a better transcript and separation of the lines. The precision of the 4K image offered by the new BenQ is exemplary, both on the edges and in the center of the screen. It should be borne in mind however that this projector is marketed at 1599 €.

 

The original version of the above review in French is at: https://www.passionhomecinema.fr/blog/index.php/28/03/2019/test-benq-w2700-lavis-de-gregory/

Share this post


Link to post
Share on other sites
44 minutes ago, MLXXX said:

I've seen a lot of posts mention chromatic aberration in relation to the W2700. 

 

I'm still trying to find confirmation by way of a clear photograph of a UHD test image that advanced ("4 times clockwise") pixel shifting that in theory should work so as to give true 4K resolution is in fact delivering that.  Why this really basic and obvious test doesn't seem to appear in user threads,  or in most formal reviews, escapes me. I've found a review in French that includes a glowing account of the resolution achieved but the image used to show that is not all that clear.  Here is the Google Translation version of the relevant part of the review:-

 

Sharpness / sharpness:

The purchaser of a 4K projector looks for image accuracy and gain in definition. These improvements can not be obtained if an effort is not made on the quality of the optics. This point, BenQ engineers have integrated well and offer for years on their models all-glass blocks.

BenQ W2700 test BenQ W2700 4K 2 Sharpness Chart

The W2700 is no exception to this rule and, despite its 4K simulation process, my Ultra High Definition pattern can not make the difference with the rendering of a native 4K projector like the Sony VW270 or the JVC N5 . Better still, I find that the DLP gives a better transcript and separation of the lines. The precision of the 4K image offered by the new BenQ is exemplary, both on the edges and in the center of the screen. It should be borne in mind however that this projector is marketed at 1599 €.

 

The original version of the above review in French is at: https://www.passionhomecinema.fr/blog/index.php/28/03/2019/test-benq-w2700-lavis-de-gregory/

Well that is much better. seems like there's too much variance from unit to unit. These reviews are strange with words like exemplary, precision and comments like it doesn't get much better than this, then they say keep in mind it's only 1500 dollars.. Hard to work out what they're 'really saying'. They're saying value for money, and indeed they are. 

Share this post


Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Sign in to follow this  

  • Recently Browsing   0 members

    No registered users viewing this page.

×
×
  • Create New...