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  #16  
Old 04-27-2014, 06:13 PM
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Originally Posted by walterbeers View Post
I've read that a 4K image is actually sharper than what our own eyes can perceive. Who needs it?
Those with more money than brains.
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  #17  
Old 04-27-2014, 09:41 PM
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To get the most from a 4K display, you also need a very large room; VK member ChrisW6ATV must have a living room the size of the state of Texas if his flat screen is over ninety inches. I live in a one-bedroom apartment and could not hope to fit a 92-inch (!) 4K television in here. My own flat panel is 19 inches, and I sit ten feet away from the set. The TV is connected to the cable system by means of coax, and I am not using a cable box; this means I am definitely not seeing anything in HD on my TV, even though the set itself is capable of 720p resolution. Even my Blu-ray player, which is connected to the set via an HDMI cable, may not be showing true HD either.

As far as movies are concerned, I have several films on standard DVD in my collection, but I haven't watched any of them yet. Most of what I watch on DVD (and cable) are classic television series from the '60s and '70s; it is extremely unlikely that these DVDs were produced in HD, as the programs themselves were not HD to begin with, but old, low-definition (!) 525-line NTSC.

I don't think, either, that the classic-TV networks on cable (MeTV, Antenna TV, RTV, et al.) are showing very old classic television series in HD, since the programs were made under the old NTSC standard; upscaling these old shows to 1080p HD will not result in true high definition, although the effect, barely noticeable though it may be, will be there. I get three classic-TV networks on cable, but none of them ever advertise that their programming is presented in HD--because it probably isn't, as I am about to explain. It is almost certain that the classic shows these networks put out are nowhere near HD when they finally go out over the cable, regardless of how much the format is fiddled with behind the scenes.

VK member walterbeers has a point as far as the sharpness issue is concerned. If it is in fact true that a 4K display can produce a sharper picture than the human eye can handle, I too would wonder who would need such a thing.

I think, since every time we turn around the industry is coming out with larger and larger LCD displays, and the sets themselves can do more than any ordinary television (even the first flat screens) could possibly do in the pre-HDTV era, owning a TV these days is (or could be, in some very competitive neighborhoods) a lot like "keeping up with the Joneses"--i. e. if someone has a 50-inch flat screen and his neighbor, for example, gets a 60-inch or larger set, the first person will get a 65-inch-plus TV, just to keep up. The neighbor will then get a 70-inch TV, prompting the other person to get an even larger display; and on and on it goes. The only way it (the competition) would stop would probably, even likely, be if one or the other gets a TV so big it crowds the family out of the house.

I can actually see something like this someday happening, as flat screens are getting larger and larger all the time. It won't be long, IMHO, before we see 100-inch and larger flat screens available for home use, but I'll bet those monsters won't fit in average-sized living rooms; as well, the price tags will be so high that very few people could afford them. Not to mention that a 100-inch flat panel TV weighs something on the order of (I'm guessing) about 200 pounds or so, not unlike the large 3-way entertainment-center console CRT TV-stereo-radio combos of the '60s through about the '80s (think Magnavox with their 25" "stereo theatre" combination set of the mid-'60s; that set must have weighed the proverbial ton).
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Last edited by Jeffhs; 04-27-2014 at 10:05 PM.
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  #18  
Old 04-28-2014, 12:25 AM
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Jeff, most TV shows from I Love Lucy up until the early 70's when they started using Video Tape were shot on 35MM film, some of the DVD's of these show were made from lesser sources so they don't look all that great but if they go back to the original negatives or prints then they can be done in HD.

I Love Lucy in fact is coming out on Bluray next month and it's already been streaming on Amazon in HD.
The original Star Trek has been on Bluray for years and it looks spectacular.

People generally buy what suits their needs and 50 or 60 inches is the new 27 inch, in other words it's pretty typical these days. As for the cost, Color TV is far cheaper today than it was in the 50's 60's and 70's, particularly if you factor in screen size vs price.

You can buy one of the cheaper 50" sets today for what would have been about $75 in 1957.

I doubt sets using panels much over 70 inches will ever be common in homes, possibly for commercial use but for the home a Projector is far cheaper and more practical for really big screens.
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  #19  
Old 04-28-2014, 12:26 AM
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ChrisW6ATV ChrisW6ATV is offline
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Quote:
Originally Posted by walterbeers View Post
I've read that a 4K image is actually sharper than what our own eyes can perceive. Who needs it?
Detail, and the number of pixels in a display needed to achieve that detail, are very much "relative", with the distance from our eyes to the display being the critical part. A "4K" display is 3840 pixels (dots) across and 2160 pixels high. Your comment "sharper than what our own eyes can perceive" is only true if you put a 4K display that is, say 55 or 65 inches diagonal (the typical sizes of the LCD sets available from Sony and others today) eight or ten feet or more away from where you sit (which, in fact, IS what most people still do with their TV sets, even HD sets). A 4K display is only worthwhile if you either:

1) Set it up so you sit VERY close to it if it is a 55-65 inch display (I mean, put it on a dining room table as if it were the centerpiece and sit "at" the table, or similar-it needs to be THAT close to see the difference from a non-4K display!), or

2) If you plan to sit at a traditional "living room watching distance" (ten feet away or more from the screen), you get a projector and a BIG screen, I mean ten FEET diagonal (120 inches) or even bigger.

The point of all this is, 4K TV sets are overkill for most people.
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  #20  
Old 04-28-2014, 12:34 AM
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Quote:
Originally Posted by Jeffhs View Post
VK member ChrisW6ATV must have a living room the size of the state of Texas if his flat screen is over ninety inches.
Jeff-

My 92-inch picture is actually from a ceiling-mounted video projector with a pull-down screen comparable to what was used with home movie projectors in the old days. My "casual" TV watching is on a 46-inch flat-panel TV set that hangs on the wall, hidden by the big screen when I use it to watch movies and sports. This living room is quite small, in fact, 10 and a half by 11 and a half feet. If I had a bigger living room, I would get a bigger screen!
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  #21  
Old 04-28-2014, 12:52 AM
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Good point Chris, most people don't need 4k unless they want a very large screen projector.
I have no intentions of running out and getting one but if that's the norm in the future when I need a new set then that's what I'll get.
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  #22  
Old 04-28-2014, 02:52 PM
jlb2 jlb2 is offline
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Quote:
Originally Posted by walterbeers View Post
I've read that a 4K image is actually sharper than what our own eyes can perceive.
Oh no, far from it. It doesn't really make sense to say that your eyes are equivalent to a X megapixel camera - their resolution is very high at the centre and much lower on the edges so it's comparing apples to oranges - but since your eyes are constantly moving to reconstruct a full-resolution image, you can consider that your vision is sort of like a camera that would have the pixel density of the centre of your retina. A quick calculation (available here) gives a resolution in the hundreds of megapixels, while 4K only achieves a miserable 8.3 megapixels. It will roughly take a 50-fold improvement in TV resolution to equal your bare eyes.

Last edited by jlb2; 04-28-2014 at 02:59 PM.
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  #23  
Old 04-29-2014, 11:48 AM
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I was wrong about the LG 3D, it's the V resolution that is halved in 3D - and annoying when viewed close. So either way, the 4K display will fix this. That's why they prefer to employ the Sony 4K projector for 3D cinema.
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  #24  
Old 04-29-2014, 02:28 PM
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Quote:
Originally Posted by ChrisW6ATV View Post
Jeff-

My 92-inch picture is actually from a ceiling-mounted video projector with a pull-down screen comparable to what was used with home movie projectors in the old days. My "casual" TV watching is on a 46-inch flat-panel TV set that hangs on the wall, hidden by the big screen when I use it to watch movies and sports. This living room is quite small, in fact, 10 and a half by 11 and a half feet. If I had a bigger living room, I would get a bigger screen!
I remember the pull-down movie screens. We had one in our basement years ago; used it with a 35mm slide projector. I can't give you exact dimensions, but our screen was quite large and wasn't exactly easy to pull down when in use. The projector was an Argus "Automatic 540", though I didn't know then (back in the late '60s) and can't imagine now what was automatic about it; it did not have even a wired remote. I don't recall the make of the screen, although I'm sure it was one of the major makes of home-movie equipment of the time.

I didn't think about projection TV when I said, in my last post, that you would need a very large living room to accomodate a 92-inch flat panel. You probably get a better-quality picture anyway with a projector. I understand these projection TV systems can produce excellent pictures given a strong TV signal, although with today's digital TV any pixelation or dropouts will stand out like a sore thumb on a large projection screen. Fortunately, those bugs have been worked out of cable systems for the most part, and what goes into your projector from any modern cable hookup is almost certainly flawless high-definition.
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  #25  
Old 04-29-2014, 09:11 PM
Rod Beauvex Rod Beauvex is offline
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Quote:
Originally Posted by Jon A. View Post
Those with more money than brains.
People who need to clearly see alot of things on the screen at once, without having to scroll.

Programmers. Artists. CAD people. Video editors, even ones not working on 4K files.
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  #26  
Old 04-29-2014, 09:26 PM
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Jon A. Jon A. is offline
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Quote:
Originally Posted by Rod Beauvex View Post
People who need to clearly see alot of things on the screen at once, without having to scroll.

Programmers. Artists. CAD people. Video editors, even ones not working on 4K files.
In other words, not the average consumer. They'll just think they need it, or will be uncool without it. That's how technology marketing works, it depends on the general public's stupidity.

Last edited by Jon A.; 04-29-2014 at 09:29 PM.
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  #27  
Old 04-30-2014, 06:43 AM
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By way of illustration, remember those awful SD plasmas that would kind of match pixel for pixel 480p? Clearly not the best way to display legacy TV programs. Upscaling to overpixeled 720 format was way better. Now extend that analogy to 1080p. What do we need? 2160p: smoother, less visually fatiguing, especially @ >70", which is what you should be looking at.
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  #28  
Old 04-30-2014, 04:19 PM
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Any predictions as to when the 8K screens will hit the consumer market? IMHO, those *should* come pretty close to being "good enough" for all but the largest home theater applications.

jr
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  #29  
Old 04-30-2014, 04:37 PM
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What are the actual movie theaters using, aren't they something like 4k already?
I believe they use three chip DLP systems.
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  #30  
Old 04-30-2014, 04:55 PM
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Here's a page that discusses various types of acuity/resolution measures:

http://webvision.med.utah.edu/book/p...visual-acuity/

The need for imaging systems to be much better than the eye in total due to the fact that the fixation point of the viewer is unknown was expounded by the researchers at RCA in the late 40s and early 50s.

And it's not a fixed number either, as the human visual system adjusts its resolution according to ambient illlumination, whereas the display is always at the same nominal brightness, so that this adjustment does not take place in a TV viewer's eye. Thus, although your visual receptor response gets noisy at low light levels (like TV "snow"), your visual system applies just enough filtering to suppress the noise. But put a TV camera in the same situation, its picture gets noisy, and then the noise is amplified along with the brightness of the scene when displayed on the monitor, and you will see it. Net result is that the camera must do much better than the eye to present an acceptable picture.
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