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April 11th, 2006, 06:44 AM | #16 |
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I' m talking about the ones that have true 1080 resolution.
My, secondhand 19 inch crt monitor (based on a Phillips design) is capable of showing above 1080 spec (4:3, letter boxed 16:9) they are cheap compared to LCD of size and res. Last month or so, there was a local sale on a true 32inch 1080 LCD for close to equivalent of $1500 (could have been 37inch, a while ago). Last year this would have been closer to $5KAU from name brands, or closer to $3KAU from this brand. Not saying it is something I would buy though. So there are an increasing number of lower cost ones out there, and prices are dropping in the last half year. |
April 11th, 2006, 07:21 PM | #17 | |
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Wayne, if you have the specs on those monitors, see what the dot-pitch of the screen phosphors is. Take the height of the screen and calculate how many dots could fit in a line of that length. Unless there's some way to resolve the horizontal scanning lines with fewer vertical dots than the numbers of lines in the display, that should give you the maximum number of lines those sets can show. Let me know if I'm wrong in equating the dot-pitch size with the maximum number of scanning lines or vertical pixels that can be displayed. Obviously, the screen dimensions of a monitor play a role in the resolution that can be shown, relative to the dot-pitch. I think that my 30-inch JVC CRT HDTV has a dot-pitch of .64mm. I'm waiting for a reply from JVC to determine this detail exactly. If this is correct, based on a screen height of 14.75 inches and a width of 26.7 inches, the screen pixel-size is 585 X 1060. This is far less than the 1080 X 1440 that is encoded in HDV, not to mention the 1080 X 1960 of full high-definition formats. However, as I said before, this TV puts on a very good picture, but I wonder how much resolution I'm missing. I calculate that the dot-pitch would have to be no more than .377mm, to resolve the full 1,080 lines of HDTV. To show the full 1,960 horizontal pixels, the dot-pitch could be no larger than .33mm.
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April 11th, 2006, 07:21 PM | #18 | |
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Wayne, if you have the specs on those monitors, see what the dot-pitch of the screen phosphors is. Take the height of the screen and the size of the dots and calculate how many dots could fit in a line of that length. Unless there's some way to resolve the horizontal scanning lines with fewer vertical dots than the number of lines in the signal, that should give you the maximum number of lines those sets can show. Let me know if I'm wrong in equating the dot-pitch size with the maximum number of scanning lines or vertical pixels that can be displayed. Obviously, the screen dimensions of a monitor play a role in the apparent resolution that can be shown, relative to the dot-pitch. I think that my 30-inch JVC CRT HDTV has a dot-pitch of .64mm. I'm waiting for a reply from JVC to determine this detail exactly. If this is correct, based on a screen height of 14.75 inches and a width of 26.7 inches, the screen pixel-size is 585 X 1060. This is far less than the 1080 X 1440 that is encoded in HDV. However, as I said before, this TV puts on a very good picture, but I wonder how much resolution I'm missing. When I was comparing different CRT HDTVs before I bought this one, I could not find others of that type that had sharper pictures. I calculate that the dot-pitch would have to be no more than .377mm, to resolve the full 1,080 lines of HDTV. If JVC informs me that the dot-pitch of my monitor is smaller than .64mm, then I'll have to recalculate the resolution potential. As soon as I get an HD camcorder, I can shoot a resolution chart and determine this in a better way than just theorizing. There are some other brands and models of CRT HDTVs that have .84mm dot-pitch. These sets could resolve only about 446 scanning lines, not even up to the full level of NTSC standard-definition. However, they could show 807 horizontal pixels, better than the 640 of SD. When I looked at those .84mm dot-pitch sets, they didn't appear to have a display that was any sharper than that. There's a lot to be desired in the resolution level of most consumer HDTV monitors. The thin-screen types that resolve up to 768 lines are better, but still short of the full HDTV specification.
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April 12th, 2006, 09:39 AM | #19 |
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Mine is 0.25mm, but this is likely diagonal with 21mm horizontal. But I know what you mean, effective beam size can be higher then pixel size, leading to overlapping on the next pixel causing interpolation.
So, mine is around 1738 Hpixels. Mine is similar to this: http://web.archive.org/web/200405192...m.tw/bm19f.htm Notice that diagonal is one of the measurements used: http://www.viewsonic.com.au/products...ecs.php?id=103 But because of the way the Phillips tube is designed I don't know, the horizontal resolution might be more. There are a number of ways it is measured, including as trio pixels. I remember something about 0.22-0.19mm pixels, and maybe 0.17mm pixels. Phillips used to have many pro class monitors. CRTs have gone off, so I haven't found any of smaller pitch ones. But it must be remembered that professional monitors have been offering much greater resolution for a number of years. 4 Mpixel, or was that 4096 pixels across, was first offered to the professional realm, in the really 80's by a professional workstation company, named something like Tektronix (long time ago). I've seen workstation monitors well advanced of PC stuff in the mid 90's. LCDs don't have phosphors and use a direct Pixel addressing, so I think it is what it says. Manufacturers tend to get sued for not Here is the one that was on sale, actually 37inch 1080 fro around $1600US (looks liked e price went back up since the sale): http://www.strathfield.com.au/ViewPr...sp?ProdID=1598 1920*1080 using the pitch specified would be 819.36mmH and 460.89mmV. Which equals the diagonal of around the 37inch claimed. Sharp is another one, and a few Electronics manufacturers have been showing their up and coming large panel 8MP SHD displays. Cheap CRT TV brands tend to use the same dot pitch for different sizes, and the resolution does fall below spec. I have done measurements, and a 80cm TV is around 720H pixels, all the smaller ones are proportionally smaller then that. I think even name brand TV cheap liens have the same problem, maybe even some more expensive lines. Monitor manufacturers tend to be more accurate and rigorous. They get sued, like over the issue of display size, where manufacturers were quoting tube size, and not display area size etc. So there is a good 2-3 hours gone again, that I needed for something else. |
April 12th, 2006, 05:47 PM | #20 | |
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April 13th, 2006, 09:47 AM | #21 |
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I don't know the last time I heard somebody refer to a TV set as a monitor. Usually only work monitors are refereed to as monitors.
Well, for editing I was referring to computer monitors. The 1080p Panel above is a flat panel TV. I went into the shop today and the girl, told me that they weren't allowed to sell anymore of them as they were all being returned. I would like to know what is happening to them ;). I don't like it's colour and movement, not that I spent much time studying it, because I thought it was another overly expensive 1388/1280 display previously, but there was something about it I didn't like. According to the stats it is bright. At a thousand dollers it would make a great desktop display, but it's not. |
April 13th, 2006, 09:53 AM | #22 |
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I guess the difference between a monitor and a tv are minor. You tend to get more resolution out of a monitor, as well as a better variety of inputs and tools, like a blue button. And a TV has a channel selector, and... Ok, that's all I've got.
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April 13th, 2006, 11:52 AM | #23 |
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Unless your talking a HDTV CRT, the differences are great, as the precision is just way out there compared to TV. The circuits required were more exacting, and I think that monitors probably trailed TV's for years in full integration. Apart from the extra complexity for precision, there probably is a greater amount of voltage swing to draw the higher resolution faster changing the dynamics of the dynamics to the circuits as well.
In this present age, all this extra complexity probably costs very little extra. The cheap CRT TV manufacturers are probably using single masks so they don't have to have a separate production lines fro each mask (or have to retool for runs for each). But make no mistake I have read about SHD being shown off on the web, and where ever for computer or for TV they are coming (well 50inch SHD, I guess it is for TV). Sony has SHD projectors, and I think there is a suggestion that there will be SHD Disks, what ever time. Would be a great premium disk priced move. There is lower cost screen technology coming (OEL and SED etc) so we expect prices to continue downwards Where ever we will reach $1000 50inch SHD anytime soon, I don't imagine, but 40inch+ HD maybe. 30inch+ SHD, would make a very good work space. |
April 14th, 2006, 06:06 AM | #24 |
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JVC is No Help
I mentioned having asked JVC to E-Mail me the specs about the dot-pitch of the screen phosphors on my HDTV. I got a very brief reply from them, that made no mention of dot-pitch or actual number of scanning lines its screen could resolve. Instead, they said that I had been misinformed about my TV being capable of 1080i. The resolution is actually 720p, the message stated. It's odd that their website describes it as being a 1080i set and having a special type of technology for upscaling to 1080i. I found that the Sony and Panasonic websites don't give the dot-pitch for their CRT HDTVs, either. I guess that specification would reveal too much about their limitations.
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April 14th, 2006, 06:44 AM | #25 |
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I forget, did you have a crt? With these things many TV's claim to be 1080i, or "HD", ready, or take 1080i input, but what they mean is that it will take the signal and down convert it to the display format. So it doesn't matter if it upscales to 1080i before it downscales to around 720p. But because it is analogue the interpolation is more smooth and natural (should I also mention, that there is also a resolution loss because of the zigzag of the scan beam not hitting the pixels directly, producing overlap).
I found a 26 inch for around $340US, that claimed 1080 input, the store owners did not know much, and the information was scarce, so I got a ruler out, measured the columns on part of the on screen logo text, and width, and multiplied out for the rest of the screen. Around SD wide 852 or 950, I forget. Why bother to buy when you will want real HD when it becomes affordable. There is something else too, measuring pixel hight doesn't really prove much on a CRT, because scanning is analogy variable again, and multiple lines can fit into one pixel cell. I have a 5 inch monitor here that is around 320*240, but it displays 480 lines. Another feature that helps to, is that the pixels are made up of red green blue cells, enabling a resolution of 3 times the pixel size horizontally. Not the best, but it helps define finer borders. That TV I rejected might even have 1080 actual scan lines in the 540 physical cell lines. But the point is that I think measuring horizontal cells is a better way to tell how serious they are (as multiple vertical scan lines can cleanly fit in one cell, but horizontally sub cells are much more course, and only show one primary colour portion for that position). But while 1080 is best on a 1080 LCD/Plasma, because it fits exactly, when you go to 720p it has to interpolate. Check out the new generation of rear projection display, they have smoother resolution screen and wider viewing angle, as they have got rid of the lenticular lens. I think this will be one of the cheapest ways to get a large mega pixel TV in the short term. Have fun. |
April 14th, 2006, 08:38 PM | #26 | |
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I've been thinking about what JVC told me about the actual screen resolution of my "1080i" CRT, being 720p. If this is actually the fact, then it would explain a lot. If they recognized that this screen had a dot-pitch too large to resolve 1,080 lines, then by downshifting to 720p, the scanned image would better match the screen. Your mention of upscaling to 1080i, then downscaling to 720p, before scanning, fits right into this. This way, they can claim to upscale to 1080i and describe it as a 1080i TV. Perhaps, they're afraid of using the dreaded "720" number in their promotions, as "a full 1,080 lines", has become an advertising catch-phrase in a very competitive market. However, everything I've found at various places on the Web, including some JVC sites, indicates that my TV upscales all inputs to 1080i and makes no mention of 720p. This wouldn't be the first time some flawed information came out of a manufacturer's customer-care department. However, on another forum, an owner of this same model described it as a 720p TV, with no further explanation. This mystery is not solved yet. I've got a lot to learn about basic TV display technology and I believe I've gotten a good start on this tonight. Much of what I've said in previous messages may be partially or completely off-base, regarding the size, numbers and arrangements of CRT screen phosphors. Apparently, JVC uses an Invar Shadow Mask, rather than the Trinitron system that Sony developed. Descriptions of these two masking systems indicate that there's a difference in the way their phosphors are grouped regarding color. If I have to acquire some more fundamentals in TV knowledge, just to understand my own set, so much the better.
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April 15th, 2006, 02:41 PM | #27 |
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I'm loosing track of the conversation, but there are TV's that accept 1080 (or SD and upscale it) and what I am saying is that the actual cell structure might be closer to 720p, so it is downscaled for LCD/Plasma, but for CRT, they might just scan it directly over the shadow mask. But one thing is sure, that 720 lines does not divide into 1080, so there will be lots of lines hitting the shadow mask boundaries. But if I didn't mention it, most people wouldn't have realised, so don't worry too much until you shop for the next one (and as you can seer there are many different ways they can do this, and they are not really goign to tell you which, so it is not worth getting hung up trying to find out which they use.
www.extremetech.com has many articles of display technology, they would know more than I can tell you. |
April 17th, 2006, 04:58 AM | #28 |
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I wonder how much a real consumer HD cam will cost once they come out!
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April 17th, 2006, 10:46 AM | #29 |
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$799, less on discount.
Sanyo HD1EX Of course you might prefer pseudo 1080i, under $1.3K on discount. Sony HC3. |
April 17th, 2006, 10:58 AM | #30 |
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I found something called Bonsai Drive, a portable unit that is supposed to capture uncompressed 4:2:2 video to a HDD. Unfortunately, I can't find anyone selling them, or any price. http://bonsaidrive.com/bonsai.html
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