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post #1 of 207 Old 08-19-2018, 12:19 AM - Thread Starter
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Image quality: 4k pixel shift vs Actual 4k

What exactly is the difference in perceptible image quality on a 110-120 screen from 12 feet away?

I want to move to 4k from my Epson 3000. But being budget conscious, I want to ensure there is a noticeable difference. Can you give me some suggestions as to why I should pick 4k over pixel shift or vice versa? Thank you.

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post #2 of 207 Old 08-19-2018, 01:28 AM
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On your screen size, at your distance, I doubt you will notice much to be honest, unless you're playing games. I'm at 8 feet from a 135" and it's very hard to notice much most the time on 4K vs JVC e-shift on movie content. If you can move yourself closer, then you'll notice more. 4K differences are in the fine details of the image.
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post #3 of 207 Old 08-19-2018, 06:25 AM
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Image quality: 4k pixel shift vs Actual 4k

By “actual” I assume you mean native 4K? Unless you count JVC’s lone $35k model, Sony is currently the only game in town for native 4K and their 4K models start at $5k and rise quickly from there.

The good news is pixel shifted 4K is quite good and is massively more affordable. If you’re in the sub $3K forum I’m going to assume your budget is $3k or under. You have pretty much three options to choose from:
DLP XPR True 4K .66” 2-way shift
DLP XPR True 4K .47” 4-way shift
Epson 4K Enhancement

It’s generally accepted that the two DLP options result in a sharper image closer to native 4K due to them producing the full 8.3 million pixels on screen. But that’s not to discount the Epson solution. While the Epsons produce only 4 million pixels their pictures are still sharper than 1080p and their two entries into the 4K market have some unique features not found on other projectors at their price points. So there is a lot to consider.

My theater is currently host to a BenQ HT2550 4K DLP projector (.47” DMD) and I love it. It’s hard to describe just how much more clarity there is to this projector compared to 1080p alternatives. I currently sit around 9 ft away from a 100” screen and I wouldn’t be able to go back. In fact, I recently had a 1080p model in here for review and while it was an superb, exceedingly sharp (for 1080p), projector I just couldn’t shake the feeling like I was missing something— even with HD material.

4K is certainly more expensive than HD— both in the cost of the display itself and content— but if the goal is to produce a large, immersive image than I highly recommend making the plunge.

The YouTube channel for the TVSPro retail store does a lot of comparisons if you want to get a good idea for the differences.

Evan over at Projector central also wrote up a nice article about 4K native vs pixel shifting. https://www.projectorcentral.com/4k-...rs-defined.htm
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post #4 of 207 Old 08-19-2018, 07:26 AM
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I have the Optoma UHD51 .47 chip 4K shifting projector and even 1080p or Blu Ray material upscaled through this is brilliant. Netflix and YouTube UHD looks amazing and I've still not seen HDR on it yet.
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post #5 of 207 Old 08-19-2018, 09:46 AM
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Quote:
Originally Posted by sage11x View Post
By “actual” I assume you mean native 4K? Unless you count JVC’s lone $35k model, Sony is currently the only game in town for native 4K and their 4K models start at $5k and rise quickly from there.

The good news is pixel shifted 4K is quite good and is massively more affordable. If you’re in the sub $3K forum I’m going to assume your budget is $3k or under. You have pretty much three options to choose from:
DLP XPR True 4K .66” 2-way shift
DLP XPR True 4K .47” 4-way shift
Epson 4K Enhancement

It’s generally accepted that the two DLP options result in a sharper image closer to native 4K due to them producing the full 8.3 million pixels on screen. But that’s not to discount the Epson solution. While the Epsons produce only 4 million pixels their pictures are still sharper than 1080p and their two entries into the 4K market have some unique features not found on other projectors at their price points. So there is a lot to consider.

My theater is currently host to a BenQ HT2550 4K DLP projector (.47” DMD) and I love it. It’s hard to describe just how much more clarity there is to this projector compared to 1080p alternatives. I currently sit around 9 ft away from a 100” screen and I wouldn’t be able to go back. In fact, I recently had a 1080p model in here for review and while it was an superb, exceedingly sharp (for 1080p), projector I just couldn’t shake the feeling like I was missing something— even with HD material.

4K is certainly more expensive than HD— both in the cost of the display itself and content— but if the goal is to produce a large, immersive image than I highly recommend making the plunge.

The YouTube channel for the TVSPro retail store does a lot of comparisons if you want to get a good idea for the differences. https://youtu.be/cDNELVmKZfk

Evan over at Projector central also wrote up a nice article about 4K native vs pixel shifting. https://www.projectorcentral.com/4k-...rs-defined.htm
+1 on "true 4K" being Sony LCOS or JVC RS4500...most of the review sites that compare the Sony's 4K VS. the 4K shifted ones oddly note that the native 1080p (4K shifted) pj outperform on 4K content and the native 4K Sony's outperform on 1080p content...my big question is will this trend continue on the next iteration of projectors, will it flip-flop, or will every pjs handling of different resolutions homogenize and be mostly the same as each other? I don't have a problem with shifted 4K as long as its tack sharp on 1080p and almost perfectly sharp on 4K, but it seems like the reverse is true.
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post #6 of 207 Old 08-19-2018, 10:27 AM
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Image quality: 4k pixel shift vs Actual 4k

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Originally Posted by pottscb View Post
+1 on "true 4K" being Sony LCOS or JVC RS4500...most of the review sites that compare the Sony's 4K VS. the 4K shifted ones oddly note that the native 1080p (4K shifted) pj outperform on 4K content and the native 4K Sony's outperform on 1080p content...my big question is will this trend continue on the next iteration of projectors, will it flip-flop, or will every pjs handling of different resolutions homogenize and be mostly the same as each other? I don't have a problem with shifted 4K as long as its tack sharp on 1080p and almost perfectly sharp on 4K, but it seems like the reverse is true.

There is a lot at play here. Beyond the actual resolution of the display and the quality of the lens you also have to consider the up scaling algorithm and how it is implemented.

Sound and Vision leveled some criticism toward Epson’s 4K enhancement saying that, when watching HD material, it had a tendency to scrub away fine detail in the image. I’ve heard the opposite of JVC’s E shift and, mechanically, they are very similar. That says to me that JVC’s algorithm might be better.

For me, I prefer the BenQ HT2550 (which uses pixel shifting) over my conventional HD projector for HD content. The up conversion works really well and allows me to sit where I want to sit (closer) without the pixel grid being visible. It’s actually quite impressive how nice HD can look on this 4K display.

Now, keep in mind, almost all pixel shifters (JVC E-shift, Epson 4K enhancement, DLP XPR .66” True 4K) use a two-way, diagonal shift. The .47 DMD in the HT2550 uses a four-way shift that more closely approximates the pixel structure you’d see with a native 4K projector. I’m not sure if that might have something to do with why I find HD on the HT2550 so compelling.

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post #7 of 207 Old 08-19-2018, 11:13 AM
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Since there are no projectors <$3,000 that simultaneously project 3,840x2,160 discrete pixels on the screen and all lower priced models rely on pixel shifting, asking this question in the Digital Projectors - Under $3,000 USD MSRP section will result in different responses than if asked in the Digital Hi-End Projectors - $3,000+ USD MSRP section. Most of those who believe there was enough of an advantage in overall projector performance to pay the price premium will likely not be reading and responding in this lower cost projector section of AVS Forum.

Having said that, the least expensive non-pixel shifting 4K model is more than three times the cost of some pixel shifters, so it requires a significant increase in budget commitment for what most consider is not a significant increase in detail for the average person viewing an average size screen from an average distance. Beyond the number of pixels on the screen and how they got there, the more expensive projectors generally have more features and superior performance in other areas beyond pixel resolution that some value more than others.

But unless you are willing to consider paying >$4,000 for the least expensive native 4K projector it's a moot point to even discuss here.
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post #8 of 207 Old 08-19-2018, 04:07 PM
 
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Quote:
Originally Posted by eightninesuited View Post
What exactly is the difference in perceptible image quality on a 110-120 screen from 12 feet away?

I want to move to 4k from my Epson 3000. But being budget conscious, I want to ensure there is a noticeable difference. Can you give me some suggestions as to why I should pick 4k over pixel shift or vice versa? Thank you.
There's an easy solution, compare them yourself

You can get all kinds of opinions on the subject because everyone's tolerance level is different from each other, which is why you need to go and find out what you're tolerant of. One of the things that I notice that has been missed in nearly all the 4K vs faux-4K discussion is the quality of the chipsets and technology behind them. Most people have simply focused on the resolution, which isn't the only difference between these 2 chipsets. They miss out on every other technical advantages of the larger and true 4K 0.66" DMD, which is simply bigger compared to the 0.47", so everything is brighter, sharper, clearer and faster. Nothing is shifting, nothing is working in the background, it's just true 4K technology. Anyone thinking logically would assume that the 0.47" would be subjected to compromises trying to match a "4K" resolution, and they would be right because contrast and brightness levels actually did suffer. Some people would be tolerant of that, while others won't. Personally, I want to wait a little longer and let faux-4K mature a bit until someone gets it right.
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post #9 of 207 Old 08-19-2018, 04:48 PM
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Image quality: 4k pixel shift vs Actual 4k

Quote:
Originally Posted by rocklee View Post
There's an easy solution, compare them yourself



You can get all kinds of opinions on the subject because everyone's tolerance level is different from each other, which is why you need to go and find out what you're tolerant of. One of the things that I notice that has been missed in nearly all the 4K vs faux-4K discussion is the quality of the chipsets and technology behind them. Most people have simply focused on the resolution, which isn't the only difference between these 2 chipsets. They miss out on every other technical advantages of the larger and true 4K 0.66" DMD, which is simply bigger compared to the 0.47", so everything is brighter, sharper, clearer and faster. Nothing is shifting, nothing is working in the background, it's just true 4K technology. Anyone thinking logically would assume that the 0.47" would be subjected to compromises trying to match a "4K" resolution, and they would be right because contrast and brightness levels actually did suffer. Some people would be tolerant of that, while others won't. Personally, I want to wait a little longer and let faux-4K mature a bit until someone gets it right.


Hey, rock, you do know that the .66” DMD uses pixel shifting as well right?
https://e2e.ti.com/support/dlp__mems...shifted-image-

“The DLP 4K UHD solution uses the high speed of the DLP 4K UHD DMD chip, along with advanced image processing from the digital display controller, as well as an optical actuator, to deliver more than 8 million pixels to the screen with just 4 million mirrors. Each mirror is capable of switching on the order of microseconds, creating two distinct addressable pixels on the screen during every frame to deliver 4K UHD resolution.”
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post #10 of 207 Old 08-19-2018, 07:04 PM
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Yep, the 0.47" XPR chip is a 4X shifter and the 0.66" XPR chip is a 2X shifter. It's pretty common knowledge that neither is true, shiftless 4K.
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post #11 of 207 Old 08-19-2018, 07:21 PM
 
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Originally Posted by sage11x View Post
Hey, rock, you do know that the .66” DMD uses pixel shifting as well right?
https://e2e.ti.com/support/dlp__mems...shifted-image-

“The DLP 4K UHD solution uses the high speed of the DLP 4K UHD DMD chip, along with advanced image processing from the digital display controller, as well as an optical actuator, to deliver more than 8 million pixels to the screen with just 4 million mirrors. Each mirror is capable of switching on the order of microseconds, creating two distinct addressable pixels on the screen during every frame to deliver 4K UHD resolution.”
Yes I forgot about that since they never talk about it as much as this 0.47" and I'm not close to being in the market for a 4K projector. Even if I get the fastest camera available I probably can't capture 2 frames shifting anyway.
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Yes I forgot about that since they never talk about it as much as this 0.47" and I'm not close to being in the market for a 4K projector. Even if I get the fastest camera available I probably can't capture 2 frames shifting anyway.
Samsung Galaxy S9 can record slow-motion at 960 fps for a brief period. I intend to use it to capture what these 2x / 4x XPR shifters are doing at 120 hz / 240hz.
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post #13 of 207 Old 08-19-2018, 11:35 PM
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Samsung Galaxy S9 can record slow-motion at 960 fps for a brief period. I intend to use it to capture what these 2x / 4x XPR shifters are doing at 120 hz / 240hz.
Is that going to see 2 movements in a millionth of a second? It's late, my math is turned off right now and I'm not a camera guy, but gut is telling me 960fps won't show anything concerning the mirror movement .

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post #14 of 207 Old 08-19-2018, 11:44 PM
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Is that going to see 2 movements in a millionth of a second? It's late, my math is turned off right now and I'm not a camera guy, but gut is telling me 960fps won't show anything concerning the mirror movement .
Not the mirrors, but the wobulator. It only changes position 240 times per second.
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post #15 of 207 Old 08-19-2018, 11:54 PM
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Shouldn't color be part of this discussion?? I know the OP wanted to know about native 4K vs pixel shifted 4K, but I am one of those that think the bigger change in "4K", is actually in color. HDR, Dobly Visio, HLG, etc..

Thoughts??
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post #16 of 207 Old 08-20-2018, 03:12 AM
 
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Shouldn't color be part of this discussion?? I know the OP wanted to know about native 4K vs pixel shifted 4K, but I am one of those that think the bigger change in "4K", is actually in color. HDR, Dobly Visio, HLG, etc..

Thoughts??
Finally, yes!
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post #17 of 207 Old 08-20-2018, 05:48 AM
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Shouldn't color be part of this discussion?? I know the OP wanted to know about native 4K vs pixel shifted 4K, but I am one of those that think the bigger change in "4K", is actually in color. HDR, Dobly Visio, HLG, etc..



Thoughts??


The resolution difference is pretty important. Not saying that HDR isn’t important. But the advantages of 4K resolution in the UHD standard has been marginalized because most people buy flat screens and, to be frank, the advantages of 4K resolution evaporate when you’re staring at a tiny 70” TV set from across the room. Simply put: TVs are too small to clearly display the advantages of 4K resolution. You need a projector for that and, ironically, projectors have lagged behind TVs in adopting 4K.

So I wouldn’t say HDR is MORE important than the 4K component. But we could settle on equally important.

I have good news and bad news. The good news is HDR looks pretty damn amazing on a projector. The bad news is it won’t look quite as amazing as your OLED. This is down to a couple of factors but the biggest two are contrast and nits. It’s no secret that projectors have lower contrast than your average OLED panel and projectors struggle to attain the 400 nits required of HDR. But that doesn’t mean that a projector won’t look markedly better with HDR material than SDR material. After all, HD/SDR has been with us for years and is pretty limited. The ability to step outside those limits, even if only just outside of them, makes for a big improvement in immersion.

Beyond that there is HDR’s expanded color reproduction. Just like in the TV set market, a projector’s capability to adhere to the DCI-P3 color gamut has a direct correlation to it’s price. At the more affordable end of the price spectrum (<$1500) where projectors like the BenQ HT2550 and Optoma UHD50 sit there isn’t much support beyond rec.709. You’ll see that coverage gradually improve until you get to the higher end models (>$2500) where projectors like the JVC X590R not only cover DCI-P3 but start to offer significant coverage of rec.2020 as well.

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From reading many many different reviews, opinions and looking at pictures. Pretty much the only way to notice a difference in pixel shifted 4k vs. true 4k is getting up quite close to non-usual viewing distances. At THAT point, people/pictures start to notice a difference in pixel shifted 4k projectors vs. true 4k projections in 4k content. HD/Full HD content can be quite different pending technology/projector, but as far as 4k source material goes, at normal viewing distance nobody can really point out any perceivable sharpness difference between the much more expense true 4k projectors and the pixel shifted ones. This is part of the reason besides price the pixel shifted 4k projectors are so popular, the advantage of the more expense true 4k projectors dont come down to sharpness, but rather contrast/blacks among other features. While in tvs the jump to 4k; HDR is the much more noticeable difference because at typical seating distance you wont see a sharpness difference really in Full HD vs. 4k unless you have a very large tv and sit fairly close...when it comes to projectors you can absolutely notice the sharpness difference in Full HD vs. 4k at normal seating distances (say 120" screen with ~10 foot seating distance), but HDR is much less noticeable because projectors are just way behind tvs right now in really reproducing proper HDR.
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post #19 of 207 Old 08-20-2018, 02:08 PM
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Not the mirrors, but the wobulator. It only changes position 240 times per second.
So the "wobulation" isn't the movement of the mirrors on the DMD ? My (limited) understanding has been that the mirror movement was the wobulation , the 60 , 120, or 240Hz refresh being handled upstream and the result is whats reflected by the mirrors . I probably need to read more , but have had only a passing interest in the inner workings .

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post #20 of 207 Old 08-20-2018, 02:24 PM
 
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Not the mirrors, but the wobulator. It only changes position 240 times per second.
Indeed, if you show, in each 4x4 block of pixels: 100% Red / 100% Green / 100% Blue / 100% Black pixels, you should see a sequence of full-frame red / green / blue / black frames at 240hz.

And a 960hz camera is more than fast enough to capture that. Modulo frame transitions which should look like tearing. I already have the shadertoy written to test things, but even a static 2160p image would suffice. This will likely only work (fully) in RGB / SDR mode, obviously, since 4:2:2 HDR10 would have some colour smearing across channels. But it should be obvious what the behaviour is anyway.

These really are 240hz 1080p projectors, with a jiggle thrown in. There's no real magic here, aside from sampling theory working as it should, and has been proven to, countless times over.
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post #21 of 207 Old 08-20-2018, 02:31 PM
 
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So the "wobulation" isn't the movement of the mirrors on the DMD ? My (limited) understanding has been that the mirror movement was the wobulation , the 60 , 120, or 240Hz refresh being handled upstream and the result is whats reflected by the mirrors . I probably need to read more , but have had only a passing interest in the inner workings .
No, the mirrors don't move, and XPR has nothing to do with the DMD, aside from processing what the DMD is currently showing, of course. This is why I consider it a disappointment they aren't using higher contrast DC3 1080p DLPs with newer, higher bandwidth (300 mhz x 2) dual DMD controllers, because then they could get both good contrast and 4K at the same time. I suspect maybe the older DC3 chips can't do 240hz well, especially not in 10-bit colour (for HDR10 banding free), but they could definitely do 120hz for sure, no problem.

These XPR projectors (and e-shift Epsons and JVCs) use mechanical actuators to shift the image which is why they're audible:

https://www.optotune.com/products/beam-shifting

The 2X ones work at 120hz which I suspect is more audible than the 240hz ones, but I'm not sure.

Every 50 or 60hz, you get either two shifts (diagonal) or four (around the four corners of a square whose sides are half the width of a pixel, and back). They can also shift the image using arbitrary DC voltages, in random directions.
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post #22 of 207 Old 08-20-2018, 03:22 PM
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Originally Posted by BattleAxeVR View Post
No, the mirrors don't move, and XPR has nothing to do with the DMD, aside from processing what the DMD is currently showing, of course. This is why I consider it a disappointment they aren't using higher contrast DC3 1080p DLPs with newer, higher bandwidth (300 mhz x 2) dual DMD controllers, because then they could get both good contrast and 4K at the same time. I suspect maybe the older DC3 chips can't do 240hz well, especially not in 10-bit colour (for HDR10 banding free), but they could definitely do 120hz for sure, no problem.

These XPR projectors (and e-shift Epsons and JVCs) use mechanical actuators to shift the image which is why they're audible:

https://www.optotune.com/products/beam-shifting

The 2X ones work at 120hz which I suspect is more audible than the 240hz ones, but I'm not sure.

Every 50 or 60hz, you get either two shifts (diagonal) or four (around the four corners of a square whose sides are half the width of a pixel, and back). They can also shift the image using arbitrary DC voltages, in random directions.
OK , first , the mirrors do move otherwise the DLP system would be broken .

I think I'm on page, that the "wobulator" dreamer is talking about is the XPR lense , which you are explaining in your post . I was looking at the other end of the chain , as in what was hz rate image was being sent , not the rate between the dmd and the xpr . My ignorance was because the couple articles I've read on it didn't mention an optical actuator oscillating in the light path between the DMD and the lens , just mirror movement , so I thought they had modified the mirror actuation in some way.

"One thing we can say about the new chip and its supporting processing, dubbed XPR, is that it comes with at least one inherent limitation that doesn’t necessarily affect other 4K displays. The system always requires playback at a 60-hertz frame rate, with the DLP chip operating at 120 Hz to enable the pixel-shifting, so there is no native 24p playback."

Is this accurate ? If so I am again confused . with this , 60 Hz signal , 120Hz DLP chip , how or why would there be 120 and 240Hz speeds for the XPR ?

Thanks for taking the time , I am in the slow beginning stages of looking at upgrading my PJ , would like 4k , but really want to know what I'm getting into , and now knowing a lense is clunking around to achieve 4k , and if there is no native 24 frame playback I'm going to have to research even more than i thought.

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post #23 of 207 Old 08-20-2018, 04:14 PM
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Optotune actually has some really excellent and honest wording in their description of their XPR-25 that I've quoted below. I've boldfaced and underscored one word that helps make this one of the most accurate descriptions of what DLP+XPR actually accomplishes:

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Optotune’s XPR-25 is an Extended Pixel Resolution 4-position Actuator. With a clear aperture of about 25mm it has been designed for Texas Instrument’s 0.47” DMD and enables the perceived image resolution to be increased from its native 1080p to 4K.
Perceived is the key word because it accurately describes the image resolution we see with these DLP XPR projectors. We don't get 3840x2160 discrete pixels on the screen at once as we get with true native 4K. But we do get four separate sets of 1920x1080 pixels sequentially flashed so rapidly on the screen that we perceive it as a 4K image. The reality of DLP+XPR is that for a fraction of the cost of the least expensive true native 4K projector we can get images we perceive to be so close in detail that it's hard to tell the difference.
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post #24 of 207 Old 08-20-2018, 04:30 PM
 
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I agree that XPR tech is fantastic, and Optotune's product page is meant for a B2B customer, namely engineers from other companies, so they wouldn't get away with marketing-speak meant to consumers.

acras, from what I can tell, it's impossible to do 24p in an even cadence, because from the source electronics point of view, it's a 60hz projector. So you get 3:2 pulldown when XPR is active.

The XPR shifters can run at 50hz (external frequency) as well. As I wrote previously, 48hz would be the ideal, so they'd just repeat each frame twice, and I would be surprised if it weren't possible to run them this way.

Personally I don't care about native 24p, as I can't watch movies as such a god-awful slow framerate. It's interpolation for me all the way. What I'm much more interested in is 240hz native operation to work, both with or without XPR activated. I think it's definitely possible. The Barco 8k models that do 4 shifts on native 4K DMDs at 60 / 240hz can also run 4K 240hz natively. Now that's amazing stuff.
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post #25 of 207 Old 08-21-2018, 12:24 PM
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For giggles can we all agree:

Native 4K is one sensor containing 4096x2160 pixels. All the pixels are activated at the same time for 4K (8meg) resolution. When showing UHD 4K, only 3840x2160 is used. All native pixels are addressable per video frame at once.

True 4k is one sensor containing 1/2 or 1/4th the pixels of a Native 4k chip with a UHD resolution of 3840x2160 (the 16:9 format). All 8meg pixels are activated for one video frame, but not at the exact same time. All 8meg pixels are addressable per video frame, but not at once.

Simulated 4K is simply doubling the pixels of a 1920x1080 sensor (usually LCD) to create a simulated 4K image of 4meg pixels. A UHD 4K image is actually downscaled from 8 meg to 4 meg. Not all 4meg pixels are activated at one time, but 4 meg is addressable per video frame.

True 4K should not be confused with Native 4K. The reason for the True 4K statement is that the projector is showing all 8meg pixels per frame as opposed to Simulated 4K. There seems to be a lot of angst over the True 4K statement. True 4K doesn't mean that the manufacturer implimented it properly in the XPR overlap of pixels--that's a whole different subjective issue.


If we can all accept this, then when texting on this and other threads, we can reflect back to this statement so everyone is on the same track regardless of what or how manufacturers state their 4K to be.
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post #26 of 207 Old 08-21-2018, 06:05 PM
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@3DBob , based on the commonly understood definition of true I can't agree with calling anything with pixel shifting true 4K. The folks who actually designed and produce the XPR mechanism honestly and accurately refer to it as creating perceived 4K from a native 1080p chip. Perceiving something to be true doesn't actually make it true. Try telling your wife or significant other that she's your one true love, which is almost as good as native love.
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post #27 of 207 Old 08-21-2018, 08:17 PM
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Image quality: 4k pixel shift vs Actual 4k

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Originally Posted by Dave in Green View Post
@3DBob , based on the commonly understood definition of true I can't agree with calling anything with pixel shifting true 4K. The folks who actually designed and produce the XPR mechanism honestly and accurately refer to it as creating perceived 4K from a native 1080p chip. Perceiving something to be true doesn't actually make it true. Try telling your wife or significant other that she's your one true love, which is almost as good as native love.


Eh... I’m not so sure about that. I don’t see “perceived” anywhere on the product page. TI actually refers to it’s 660TE solution (.66 DMD) as having a “true 4K resolution” of 3840 x 2160 “on screen”. Of course they’re counting the DMD, the processor and the actuator as one complete system and in that respect you could make the argument...

I don’t know. Judge for yourself.
http://www.ti.com/product/DLP660TE

In either case, it’s not like TI are the only ones to point fingers at here. Check out Epson’s description of their 4K enhancement:
“Using the projector's 4K Enhancement Technology, you can receive 4K (3840 × 2160) signals and project ultra high-definition images. This technology shifts each pixel diagonally by 0.5 pixels to double the image resolution.”

https://files.support.epson.com/doci...adjusting.html

I love how they throw in the “double the image resolution” but don’t specify what is being doubled.


But that’s not the half of it. Check out JVC’s description of their E-shift:
“Experience absolute presence as images seem to float in mid-air, and you forget the existence of the screen. Be totally immersed in the world that is portrayed, as images envelop you. Beyond 2K is a new world of moving experiences that only 4K can deliver.
JVC's e-shift 3 technology is able to reproduce the finest nuances and unique tone of every visual work, enabling you to enjoy a 4K-resolution* image with extreme realism and presence in your home theatre environment.

*3840 x 2160”

https://eu.jvc.com/microsite/eu/dla-...feature01.html

I mean, they don’t even elude to the fact that half the pixels are missing and yet no one bats an eye. But if a DLP manufacturer doesn’t specifically mention in every part of their product description that there are less than 8 million mirrors on the DMD then someone grab the pitch forks! Lol!


I don’t know. I’ll keep calling it what I have been: pixel shifted 4K. That seems to be the most adequate description. Meanwhile, I’ll be referring to JVC and Epson’s solutions as 4K simulation— because that’s what they are.

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Quote:
Originally Posted by Dave in Green View Post
@3DBob , based on the commonly understood definition of true I can't agree with calling anything with pixel shifting true 4K. The folks who actually designed and produce the XPR mechanism honestly and accurately refer to it as creating perceived 4K from a native 1080p chip. Perceiving something to be true doesn't actually make it true. Try telling your wife or significant other that she's your one true love, which is almost as good as native love.
So your claim is that pixel shifting doesn't actually create all the pixels that are expected of 4k resolution?
I agree that not all combinations of those pixels are possible with pixelshifting (such as alternating black-white patterns), but imo all the pixels are there.
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post #29 of 207 Old 08-22-2018, 08:23 AM
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@Dave in Green : I'm frankly not arguing that True 4K is the right expression for e-shifted 4K (8 meg). I'm just trying to establish what the industry from a marketing perspective is calling it (8 meg addressable pixels per video frame), so we don't get twisted in our statements. If we do call it e-shifted 4K, then there is the problem with 8 meg e-shifted and 4 meg e-shifted. There are a lot of problems with True 4K, since Native 4K is actually 4096x2160 pixels and True 4K is the UHD version at 3840x2160. I don't see many arguing this point when in reality practically no TV or projector shows the full Native 4K. I did a quick search and every TV I saw said UHD 4K--so I guess they aren't Native 4K either. It's all a matter of semantics, and my wife is my one true love...
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Quote:
Originally Posted by sage11x View Post
Eh... I’m not so sure about that. I don’t see “perceived” anywhere on the product page. ...
You are looking at TI's description. I was referencing Optotune's description as you can see in my post #23 which refers to the link posted by @BattleAxeVR . Optotune is responsible for the XPR-25 beam shifting mechanism which they clearly state "enables the perceived image resolution to be increased from its native 1080p to 4K."

Anyway this has all been hashed out in the dedicated 4K discussion thread. From my perspective the only new data point that's been added to that previous discussion is the Optotune description of their XPR-25 beam shifter that enables TI's native 1080p DMD to create what can be perceived as a 4K image. As I already stated, something that is perceived as true isn't necessarily true. Marketers love being able to use the word true because it implies to the uneducated that what they label true is as good as it gets.

@3DBob , anyone is free to use whatever description they want. For others (including me) the only true 4K is native 4K -- 1:1 pixel mapping of content with discrete, non-overlapping pixels all displayed simultaneously. All the pixel shifting models are in various subcategories of perceived 4K. I personally think pixel shifting 4K offers tremendous value and is currently more relevant to more projector buyers than native 4K. But I think it's deceptive to market any pixel shifter as true or genuine 4K and expect the average consumer to understand that native 4K is technically superior.

@racemaniac , with pixel shifting all the pixels can be there. But they aren't displayed simultaneously and because they are shifted from a native 1080p chip (1920x1080 micro-mirrors) the individual pixels are larger than native 4K pixels so they overlap. Look at the image on the Optotune site that clearly shows the pixel overlap. Also, if you haven't already read it, the dedicated 4K thread covers most of the technical and marketing issues.

optotune.com/products/beam-shifting

avsforum.com/forum/68-digital-projectors-under-3-000-usd-msrp/2939832-what-constitutes-4k.html
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Last edited by Dave in Green; 08-22-2018 at 09:50 AM.
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