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Posted

For clarity:

On that front, streaming 4K from Netflix (yes, it's very painful watching something in chunks of a few seconds each as it buffers) only looks very marginally better (like single digit %'s), and only at some times, to 1080P blu-rays upscaled by the TV - I haven't yet however had the chance to A/B test the exact same content - so that's just a general observation.

.... that low bitrate streaming 4K (Netflix=15mbps) has very marginal benefits over blu-ray 1080P

Proper 1080P vs 4K comparisons just won't be possible until we get 4K Blu-ray - and it becomes an apples-to-apples, real-world, A/B test.

One thing that is clear, and has never changed, is that bitrate matters more than resolution, as soon as it's being compromised.

  • Like 1
Posted

More thoughts on this topic...

How can we see stars? the navigation lights on airplanes several KM's overhead? Surely these are all well outside of the bounds of these visual acuity specs be popularised to argue against the benefits of 4K TV's online?

I have a really simple test I'm going to try tomorrow night: I'm going to make a 3840x2160 PNG file.. it's going to be black, except for just a single white pixel. I'm then going to park my TV on the front porch, and see just how far I have to go before I don't see that white pixel anymore....

I'm not a gambler, but I'm 'betting' my test makes a mockery of all these "you can't see 4K @ xx feet" charts wink.png

Is it a flawed experiment?

  • Like 1
Posted

The problem with your test is a similar one to phoneme boundaries in audio..

You will know where the where dot is.. And you will retreat while knowing ts there.. Hence your brain will continue to 'see' it, when your visual acuity may not..

  • Like 1
Posted

The problem with your test is a similar one to phoneme boundaries in audio..

You will know where the where dot is.. And you will retreat while knowing ts there.. Hence your brain will continue to 'see' it, when your visual acuity may not..

OK, I get the idea. So what if I find my own max. distance, then get some bystanders at that location and ask them if they can see it? smile.png

Perhaps I should just use a correctly sized version of the Snellen chart others are using as the basis of their argument?

How about inverting the colors of the chart (make it white on black, rather than black on white)?

On the whole Snellen chart thing, the basis of it is, whether or not you are able to distinguish the actual letters - which is very different to seeing *something* vs *nothing* ....

smile.png

Posted

Perception is a very strange thing.. far more linked to the brain and interpolation than people think..

Eg we only see in color for a small central section of our eyes.. the rest of the color we perceive is simply the brain 'filling in' the colors.. if the color is swapped by an equal tone / brightness while we are looking not directly at it, we still perceive it to be the old color when thats clearly wrong etc etc..

  • 2 weeks later...
Posted

Oh, I forgot to update this thread ...

I did the test - even at a distance of ~25M (the furthest I could get away in a straight line), the single pixel was visible. Everyone saw it. However, visibility was completely brightness driven - as you turn that down, it became harder and harder to detect. Also, if I added ambient light (I have several garden lights making about 500 lumens each), you just couldn't see it anymore.

OK, not as scientific as trying to read the letter "E" on an eye chart, but enough to at least satisfy me that I'm not imagining I can see things the internet says I can't ;)

Posted

I've also written about my experience with Onkyo TX-NR636 receiver, and how to configure it with Kodi / OpenELEC.

http://www.cnx-software.com/2015/02/05/onkyo-tx-nr636-review-pass-through-openelec-kodi/

It's not really a detailed review, as there would be so many items to test with this device, and I simply wrote about the basics.

Just one thing to mention: the power specs on these mainstream AVR's are all rated with only one channel running - none of them will actually make their published power into a full speaker load. That said, I suspect the Onkyo has more than enough power to send those little Pioneer speakers to moon ;)

Posted

Oh, I forgot to update this thread ...

I did the test - even at a distance of ~25M (the furthest I could get away in a straight line), the single pixel was visible. Everyone saw it. However, visibility was completely brightness driven - as you turn that down, it became harder and harder to detect. Also, if I added ambient light (I have several garden lights making about 500 lumens each), you just couldn't see it anymore.

OK, not as scientific as trying to read the letter "E" on an eye chart, but enough to at least satisfy me that I'm not imagining I can see things the internet says I can't wink.png

It looks like I'm not alone on this smile.png

Please hear me out. Rtings has been incredibly unbiased to date and I greatly respect that, especially in today's society. Please keep that up for this: Despite previous studies, I honestly believe that I have developed a new breakthrough method to determine the proper screen size to distance ratio. It essentially proves the studies previously used for this are not entirely accurate in the context of TVs. Again, please hear me out. I generated an uncompressed image containing a plain pure black background, with a single pure white pixel in the center of it. I ensured my uncompressed images that I generated were 1920x1080. I then made variations with different single colored backgrounds and pixels, then other variations with a larger box around the single pixel to help me stay focused on where it is from father distances. I then displayed these on a 1080p OLED (as close to infinite contrast as possible) and measured how far away I was when I could no longer detect the pixel. I did this in an average lit setting and in a pitch black room. I had to move away extremely slowly to stay focused on it, but in all cases, with the exception of the black and white, I was 9-39% farther away than what you (and the entire internet for that matter) claims to be the absolute minimum distance in which a human should be able to detect 1 pixel worth of detail for that particular screen size to distance ratio. I exclude the black screen with white pixel numbers simply cause our eyes detect the detail differently with black and white than when color is involved. Also, I was able to detect the single white pixel from significantly farther away than the color on color variants, and was unable to precisely measure that distance with my tools. I partially attribute my findings to the fact that TV's emit light and our eyes can detect small details better from bright screens than in other, everyday, less bright situations. I also believe that our eyes are generally slightly better than what previous studies have found, and that previous studies didn't test enough variations of settings/material. Regardless, the bottom line is that in all the scenarios I tested, I was able to see a single pixel from farther away than I was supposed to be able to according to the standards described on this page. If you happen to still have a plasma laying around, or better yet have an OLED in any time soon, please replicate this test in black and white, colors, dark and typical rooms, with and without a box around the pixel, etc and see for yourselves. Thank you very much for your time.

This is interesting. The above formula is based on that the average visual acuity needed to discriminate two contours is separated by 1 arc minute. The best example of this is for the letter E, more specifically the 3 branches of the letter. 20/20 vision means that the average person won't distinguish between those branches when the E letter's height is less than 5 arc minute. Further than that and the branches just blend in and it looks like a rectangle. This test is a little bit harder than your test. But your test raises an interesting question, which is to about which test is better suited for a TV? I don't really have an answer to that. And as you pointed out, the contrast of the TV also has a role to play in this. The lower the contrast, the closer you need to be to see in detail. Anyway, thanks for sharing. This is a good discussion and you brought in interesting results. Thanks.
He was testing with an OLED screen, which are not as bright as LED backlit LCD's though...
Posted

Your claiming to see a single pixel on a 4k TV at 25m ???

Not claiming, stating, and not just me, that that others - wife, kids, and neighbors could see it too.

Source was a my macbook, showing a 3840x2160 PNG file, all back except for 1 lonely, white, pixel.

The TV was setup with LED backlight at full, contrast full, brightness at 35% (higher starts making the blacks go too gray), LED local dimming off (with this on, the single pixel was lighting up only maybe 5%). I also disabled all picture enhancers (sharpness, motion smoothing, mpeg de-noiser etc).

The TV + stand was parked on the house front entry steps, so it was only just below eye level when standing on the driveway, and right at eye level once out on the street. Test was done at around 8:00 at night, partly cloudy skies, no outdoor lights on, and no meaningful ambient light from neighbors.

I also used my phone camera to get a closer view and confirm that indeed only one pixel was lighting up.

Anything else you'd like to know? :)

The only real surprise was the amount of picture algorithms this TV has enabled by default - and how many of them conspired against my single white pixel to make it not light up 100% without tweaking ;)

Posted

Your claiming to see a single pixel on a 4k TV at 25m ???

The key point I think everyone is overlooking, is that TV's transmit light - and the brighter the light transmitted, the further away it will remain visible. Just like stars, and lasers.

Even as I type this, I can look out my window and make out the leafless twigs on a tree that's well over 100M away (silhouetted against a blue/gray sky), and those twigs can't be more than about 3mm across. Would I be able to read a letter E on them? of course not smile.png Can I see the colors and texture of them? No. Can I see them though? yes! Would I be able to see them clearer and/or further away if it was a dark night and they transmitted light? for sure :)

Posted

Oh, I forgot to update this thread ...

I did the test - even at a distance of ~25M (the furthest I could get away in a straight line), the single pixel was visible. Everyone saw it. However, visibility was completely brightness driven - as you turn that down, it became harder and harder to detect. Also, if I added ambient light (I have several garden lights making about 500 lumens each), you just couldn't see it anymore.

OK, not as scientific as trying to read the letter "E" on an eye chart, but enough to at least satisfy me that I'm not imagining I can see things the internet says I can't wink.png

It looks like I'm not alone on this smile.png

Please hear me out. Rtings has been incredibly unbiased to date and I greatly respect that, especially in today's society. Please keep that up for this: Despite previous studies, I honestly believe that I have developed a new breakthrough method to determine the proper screen size to distance ratio. It essentially proves the studies previously used for this are not entirely accurate in the context of TVs. Again, please hear me out. I generated an uncompressed image containing a plain pure black background, with a single pure white pixel in the center of it. I ensured my uncompressed images that I generated were 1920x1080. I then made variations with different single colored backgrounds and pixels, then other variations with a larger box around the single pixel to help me stay focused on where it is from father distances. I then displayed these on a 1080p OLED (as close to infinite contrast as possible) and measured how far away I was when I could no longer detect the pixel. I did this in an average lit setting and in a pitch black room. I had to move away extremely slowly to stay focused on it, but in all cases, with the exception of the black and white, I was 9-39% farther away than what you (and the entire internet for that matter) claims to be the absolute minimum distance in which a human should be able to detect 1 pixel worth of detail for that particular screen size to distance ratio. I exclude the black screen with white pixel numbers simply cause our eyes detect the detail differently with black and white than when color is involved. Also, I was able to detect the single white pixel from significantly farther away than the color on color variants, and was unable to precisely measure that distance with my tools. I partially attribute my findings to the fact that TV's emit light and our eyes can detect small details better from bright screens than in other, everyday, less bright situations. I also believe that our eyes are generally slightly better than what previous studies have found, and that previous studies didn't test enough variations of settings/material. Regardless, the bottom line is that in all the scenarios I tested, I was able to see a single pixel from farther away than I was supposed to be able to according to the standards described on this page. If you happen to still have a plasma laying around, or better yet have an OLED in any time soon, please replicate this test in black and white, colors, dark and typical rooms, with and without a box around the pixel, etc and see for yourselves. Thank you very much for your time.

This is interesting. The above formula is based on that the average visual acuity needed to discriminate two contours is separated by 1 arc minute. The best example of this is for the letter E, more specifically the 3 branches of the letter. 20/20 vision means that the average person won't distinguish between those branches when the E letter's height is less than 5 arc minute. Further than that and the branches just blend in and it looks like a rectangle. This test is a little bit harder than your test. But your test raises an interesting question, which is to about which test is better suited for a TV? I don't really have an answer to that. And as you pointed out, the contrast of the TV also has a role to play in this. The lower the contrast, the closer you need to be to see in detail. Anyway, thanks for sharing. This is a good discussion and you brought in interesting results. Thanks.
He was testing with an OLED screen, which are not as bright as LED backlit LCD's though...

I think the distance charts are for perceived quality, so if you just display a white spot on a black surface, it's quite a different test, even though it shows the distance at which people can see a dot on a 4K TV.

But now for example if you draw three pixels (blue, red, green) next to each other, and step back until you can not distinctively see the pixels, I'm sure the distance would be much shorter.

I've checked rtings.com with my 42" screen. Optimial distance: 1.22m. That's really close, just like the other chart I included in my TV review.

I've watched Big Buck Bunny video at 1080p and 2160p with a 4K media player (Zidoo X9) sitting at about 2 meters from my 42" 4K TV.

* bbb_sunflower_2160p_30fps_normal.mp4 @ 2160p30 video output

* bbb_sunflower_1080p_60fps_normal.mp4 @ 1080p60 video output

I think I can see some differences, but it's far from being obvious. My eyes are not that good though (short-sighted with glasses).

Another way to test would be to get a bunch of good quality 1080p and 4K videos, get some software or somebody to play the files randomly, and mark which ones are 1080p and 4K, and compare with actual results once the test is completed.

  • Like 1
Posted

Oh, I forgot to update this thread ...

I did the test - even at a distance of ~25M (the furthest I could get away in a straight line), the single pixel was visible. Everyone saw it. However, visibility was completely brightness driven - as you turn that down, it became harder and harder to detect. Also, if I added ambient light (I have several garden lights making about 500 lumens each), you just couldn't see it anymore.

OK, not as scientific as trying to read the letter "E" on an eye chart, but enough to at least satisfy me that I'm not imagining I can see things the internet says I can't wink.png

It looks like I'm not alone on this smile.png

Please hear me out. Rtings has been incredibly unbiased to date and I greatly respect that, especially in today's society. Please keep that up for this: Despite previous studies, I honestly believe that I have developed a new breakthrough method to determine the proper screen size to distance ratio. It essentially proves the studies previously used for this are not entirely accurate in the context of TVs. Again, please hear me out. I generated an uncompressed image containing a plain pure black background, with a single pure white pixel in the center of it. I ensured my uncompressed images that I generated were 1920x1080. I then made variations with different single colored backgrounds and pixels, then other variations with a larger box around the single pixel to help me stay focused on where it is from father distances. I then displayed these on a 1080p OLED (as close to infinite contrast as possible) and measured how far away I was when I could no longer detect the pixel. I did this in an average lit setting and in a pitch black room. I had to move away extremely slowly to stay focused on it, but in all cases, with the exception of the black and white, I was 9-39% farther away than what you (and the entire internet for that matter) claims to be the absolute minimum distance in which a human should be able to detect 1 pixel worth of detail for that particular screen size to distance ratio. I exclude the black screen with white pixel numbers simply cause our eyes detect the detail differently with black and white than when color is involved. Also, I was able to detect the single white pixel from significantly farther away than the color on color variants, and was unable to precisely measure that distance with my tools. I partially attribute my findings to the fact that TV's emit light and our eyes can detect small details better from bright screens than in other, everyday, less bright situations. I also believe that our eyes are generally slightly better than what previous studies have found, and that previous studies didn't test enough variations of settings/material. Regardless, the bottom line is that in all the scenarios I tested, I was able to see a single pixel from farther away than I was supposed to be able to according to the standards described on this page. If you happen to still have a plasma laying around, or better yet have an OLED in any time soon, please replicate this test in black and white, colors, dark and typical rooms, with and without a box around the pixel, etc and see for yourselves. Thank you very much for your time.

This is interesting. The above formula is based on that the average visual acuity needed to discriminate two contours is separated by 1 arc minute. The best example of this is for the letter E, more specifically the 3 branches of the letter. 20/20 vision means that the average person won't distinguish between those branches when the E letter's height is less than 5 arc minute. Further than that and the branches just blend in and it looks like a rectangle. This test is a little bit harder than your test. But your test raises an interesting question, which is to about which test is better suited for a TV? I don't really have an answer to that. And as you pointed out, the contrast of the TV also has a role to play in this. The lower the contrast, the closer you need to be to see in detail. Anyway, thanks for sharing. This is a good discussion and you brought in interesting results. Thanks.
He was testing with an OLED screen, which are not as bright as LED backlit LCD's though...

I think the distance charts are for perceived quality, so if you just display a white spot on a black surface, it's quite a different test, even though it shows the distance at which people can see a dot on a 4K TV.

But now for example if you draw three pixels (blue, red, green) next to each other, and step back until you can not distinctively see the pixels, I'm sure the distance would be much shorter.

I've checked rtings.com with my 42" screen. Optimial distance: 1.22m. That's really close, just like the other chart I included in my TV review.

I've watched Big Buck Bunny video at 1080p and 2160p with a 4K media player (Zidoo X9) sitting at about 2 meters from my 42" 4K TV.

* bbb_sunflower_2160p_30fps_normal.mp4 @ 2160p30 video output

* bbb_sunflower_1080p_60fps_normal.mp4 @ 1080p60 video output

I think I can see some differences, but it's far from being obvious. My eyes are not that good though (short-sighted with glasses).

Another way to test would be to get a bunch of good quality 1080p and 4K videos, get some software or somebody to play the files randomly, and mark which ones are 1080p and 4K, and compare with actual results once the test is completed.

For sure, your example of RGB lines is going to look like a white blob, once you're far enough away ;)

I think my real-life tree example is probably a better way to look at at... we can't see clear details, but we can see some definition, that defies these distance charts we're all seeing based on Snellen vision tests.

Here's my prediction: we're going to see a bunch of about-faces all over the internet once we have proper, not-so-bitrate-starved, 4K blurays.

I'm curious, what is your perception of differences at say 1.3M? Testing differences at a distance of 2M (64% longer than these seating distance charts suggest), is giving them a very wide margin..

Posted

Your claiming to see a single pixel on a 4k TV at 25m ???

The key point I think everyone is overlooking, is that TV's transmit light - and the brighter the light transmitted, the further away it will remain visible. Just like stars, and lasers.

Even as I type this, I can look out my window and make out the leafless twigs on a tree that's well over 100M away (silhouetted against a blue/gray sky), and those twigs can't be more than about 3mm across. Would I be able to read a letter E on them? of course not smile.png Can I see the colors and texture of them? No. Can I see them though? yes! Would I be able to see them clearer and/or further away if it was a dark night and they transmitted light? for sure smile.png

when I win a lottery and buy a house with a really big living room - say 25m across, I will come to you for best recommendation for 4k tv so I can see the pixel on the other side :)

Posted

Read this on the net today

4K Blu-ray is officially on the way. According to Victor Matsuda, Chairman of the Blu-ray Disc Association Global Promotions Committee, the BDA expects the specs for 4K Blu-ray to be finalized in the first half of 2015, paving the way for commercial availability by the end of the year. This means we can expect to see actual 4K Blu-ray movies and players available in stores by Christmas next year.

Apart from the jump to 4K resolution (3840 × 2160p) we can also expect 4K Blu-ray to support higher frame rates (up to 60fps), an expanded color gamut along with high dynamic range (HDR), as well as HEVC/H.265 encoding to compress 4K movies more efficiently and allow for higher bit rates. The group is currently exploring the possibility of increasing the disc capacity to 66GB or 100GB.

The news was confirmed by representatives on the show floor at IFA 2014 in Berlin, which opened its doors to visitors today.

Posted

Read this on the net today

4K Blu-ray is officially on the way. According to Victor Matsuda, Chairman of the Blu-ray Disc Association Global Promotions Committee, the BDA expects the specs for 4K Blu-ray to be finalized in the first half of 2015, paving the way for commercial availability by the end of the year. This means we can expect to see actual 4K Blu-ray movies and players available in stores by Christmas next year.

Apart from the jump to 4K resolution (3840 × 2160p) we can also expect 4K Blu-ray to support higher frame rates (up to 60fps), an expanded color gamut along with high dynamic range (HDR), as well as HEVC/H.265 encoding to compress 4K movies more efficiently and allow for higher bit rates. The group is currently exploring the possibility of increasing the disc capacity to 66GB or 100GB.

The news was confirmed by representatives on the show floor at IFA 2014 in Berlin, which opened its doors to visitors today.

Panasonic actually did booth demos of 4K Bluray at least month's CES - so it's progressed a lot since the September IFA event (where that news came from). My guess is the next piece of news won't be too far behind the official launch of DTS:X in March, which wraps up the new tech portfolio for next-gen home theatre.

Posted

Super. Just ordered the 49" for my bedroom smile.png

Wow that was fast! Did you order online? I considering buying one online too, but I worry about warranty...

How would that work? Just bring the TV at the closest LG service center, and they'll cover the repair if if it under warranty?

Yep, ordered online from cdiscount for 27,030 delivered. Looks like they are out of stock now though: http://www.cdiscount.co.th/lg-ultra-hd-smart-led-tv-49-inch-49ub820t-19041

In my experience, there's no real advantage buying from bricks and mortar, as all warranty claims need to go to the manufacturers service centre anyway. I have never had a problem getting warranty service when buying from Thai vendors on or offline (well tested with the 2 Samsung TV's I own).

Looks like the 42" is sold out too: http://www.cdiscount.co.th/lg-ultra-hd-smart-led-tv-42-42ub820t-17293 which means that now costs 21.5K from Lazada (next best price).

I bought a 42 inch LG smart TV from Big C on Pattaya Klang and used it for about two weeks before the screen started to flicker which I later found out was because of the HDMI ports so I returned it to Big C and they promptly swapped it out for a new one. I happily used the new TV for about 6 months and it suddenly died one day and wouldn't power on so I contacted LG and delivered the TV to their authorized repair center off Pattaya Klang. Now fast forward 13 months later and I was still trying to get them to fix the TV but I kept getting the same old song and dance that they are waiting for parts to arrive. I finally ended up calling the LG corporate office and told them I was going to put the TV in front of their office pour gas on it and lite it on fire. Well I had a new TV in the box about 2 weeks later.. I wouldn't take another LG if you gave it to me..

Kurt

  • 3 weeks later...
Posted

While I like the idea of 4K Blu-Ray, I would be hesitant about buying my favourite movies all over again in yet another format. I'm nearly broke after buying them in VHS video, Laserdisc, regular DVD and standard Blu-Ray and have run out of shelf space to add 4K Blu-Ray. I think buyer fatigue will have a strong impact on sales and suspect many fans with large libraries will be content to upscale from 1080.

Posted

While I like the idea of 4K Blu-Ray, I would be hesitant about buying my favourite movies all over again in yet another format. I'm nearly broke after buying them in VHS video, Laserdisc, regular DVD and standard Blu-Ray and have run out of shelf space to add 4K Blu-Ray. I think buyer fatigue will have a strong impact on sales and suspect many fans with large libraries will be content to upscale from 1080.

Yeah, I can't see too much point in replacing your back library... but if you still buy movies on media, it kinda makes sense to start buying 4K when it's released ;)

Posted

While I like the idea of 4K Blu-Ray, I would be hesitant about buying my favourite movies all over again in yet another format. I'm nearly broke after buying them in VHS video, Laserdisc, regular DVD and standard Blu-Ray and have run out of shelf space to add 4K Blu-Ray. I think buyer fatigue will have a strong impact on sales and suspect many fans with large libraries will be content to upscale from 1080.

Yeah, I can't see too much point in replacing your back library... but if you still buy movies on media, it kinda makes sense to start buying 4K when it's released wink.png

I would like some 4k Blu-rays for my UHD tv but i suspect in thailand they will be too expensive, like 2,000 baht a time. I am not buying all my old movies again at that price.

  • Like 1
Posted

If you use xbmc and a receiver with upscaler then try watching the latest season of house of cards. If you have the genisis addon then down load the 1080P stream. It should be the first one on the list. I watched this yesterday and the picture quality was the best i've seen on my 4k TV. I don't know if I as getting 4k but to my eye it mached the quality of the promotional video loop they play in the store when displaying the 4k TV's.

I don't have a blu-Ray player yet but I have been looking at an oppo blu-Ray ( cost roughly 20k) that they say has upscaling capability.

BTW this is the first time I saw a stream on xbmc with a 1080p designator. I didn't think I'd be able to download it on my internet but there was no buffering at all. Later it was depressing to go back to watching SD quality downloads

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