Which 30 INCH CRT HDTV HAS THE MOST Horozontal Lines Of Resolution?

Which 30 inch CRT HDTV has the most horizontal lines of resolution? :confused:

They're all 1080i resolution.

:confused: There was a difference in the HD sharpness of the Sony 34XS955 that I use to own and later on I owned a Sony KV-34HS420 which does'nt have as good a picture in HD. My question to YOU is"if all these HDTV'S are in 1080i and all the SAME as you said...then why would a Sony be better than a Sumsung HDTV? Example: I want a 30 inch tube HDTV for my mom...are you saying that the Sony's picture will be better than the 30 inch Samsung for the same price?

The 1080i number is VERTICAL resolution... horizontal res may be called out as pixels of res, but that is 'per vertical height'... so TOTAL horizontal pixels will be the number times 16/9.

so TOTAL horizontal pixels will be the number times 16/9.
Not true--my Sanyo HDTV 1080i only can display about 800 horizontal pixels--far short of the 1920 required for "true" 1920x1080 resolution.

P-Sz

These Samsung "HDTV"s being discussed - They come in a 26" and a 30" versions selling for $650 and $850 or so at retail. -After trying to explain some of the points discussed here on another idientical thread by the same starter I went to the local CC and measured the red stripe pitch on these Samsungs - with my naked eye! - They both had about 21 red stripes per inch horizontally - the 26 has about 500 red stripes and the 30" about 600 across the entire width of the screen. If you watch the picture from about 5 feet - right for this size - and the screen goes red - it looks like a red picket fence - The "800 lines of horizontal resolution" probably refers to the number of possible black or white dots (400 each) across the entire screen - not the correct way of expressing lines of horizontal resolution - correctly it would be 9/16 of that figure - about 450 - If you buy one of these things be prepared for some of the most awful CRT images you will ever see on a modern TV -Unfortunately the CEI spec for HDTV allows this sort of junk to be called HDTV if the screen is retraced 720 or 1080 times per second- the 1280 and 1920 horizontal pixels are not part of the Consumer Electronic Industry paradigm - You could be watching the fuzziest image as long as it had 720 or 1080 scan lines it's HDTV according to the Manufacturers - Don't confuse the CEI specs (HDTV equipment-the HDTV logo) with the ATSC specs (DT broadcast formats)

Thankyou for finding out about this peice of junk.I'm not going to buy it after all. :eek:

correction---- :(
-Unfortunately the CEI spec for HDTV allows this sort of junk to be called HDTV if the screen is retraced 720 or 1080 times per second- ]correction should be: Unfortunately the CEI spec for HDTV allows this sort of junk to be called HDTV if the screen is retraced 720 or 1080 times per frame-

Not true--my Sanyo HDTV 1080i only can display about 800 horizontal pixels--far short of the 1920 required for "true" 1920x1080 resolution.

P-Sz

The only use I could find in the manuals of the number 800, was as the number of lines of resolution of the A/V inputs (SVideo, Composite). I didn't find any ref to any horizontal res... :confused:

It is because of the spec being 'per image height' that it's necessary to multipy by 16/9.

The only use I could find in the manuals of the number 800, was as the number of lines of resolution of the A/V inputs (SVideo, Composite). I didn't find any ref to any horizontal res... :confused:

It is because of the spec being 'per image height' that it's necessary to multipy by 16/9.

The horizontal resolution wasn't in the manual at all; I saw it on a web page somwhere. Best Buy reports it in the specs on their Tvs, such as: http://www.bestbuy.com/site/olspage.jsp?id=1077626340598&skuId=6407854&productCategoryId=cat03002&type=product

see also http://www.highdefforum.com/archive/index.php/t-1316.html

Here's a quote from the BB glossary that you get when you click on 'horizontal resolution'....

horizontal resolution Rating, measured in lines, of the fine detail of a TV picture. The greater the number of lines -- measured from lines on a test pattern, not to be confused with scanning lines -- the higher the resolution and the better the picture. Current U.S. NTSC analog maximum is 480 lines. Horizontal resolution is measured only over a width equal to the height of the picture (a square), not over the entire screen, which is slightly wider than it is high. (See 4:3, lines of resolution)

for 800 lines total wouldn't that be 9/16 of 800 or 450 for a 16:9 tube?

Am I correct that a CRT will have a certain "dot pitch"? That is, the distance between display dots will depend on the masking?
If that is true, and I calculate the required dot pitch for the full 1080 resolution for a 30", 16:9 tube, I find that it is around 0.35mm.
Again, if that is correct then the resolution of all the 30" sets I've heard of can be only about half the 1080 spec.
Would someone who REALLY knows respond?

for 800 lines total wouldn't that be 9/16 of 800 or 450 for a 16:9 tube?

No, that's 800 lines over a width that is equal to the screen height. Therefore the number of lines over the WHOLE width is 800 x 16/9 = 1422.

Am I correct that a CRT will have a certain "dot pitch"? That is, the distance between display dots will depend on the masking?
If that is true, and I calculate the required dot pitch for the full 1080 resolution for a 30", 16:9 tube, I find that it is around 0.35mm.
Again, if that is correct then the resolution of all the 30" sets I've heard of can be only about half the 1080 spec.
Would someone who REALLY knows respond?

By trigonometry, screen width of a 30" set is 664 mm. Dividing by .35 would yield 1897 pixels...

I went looking for specs on Sony, Sammy, Tosh and didn't find any... no hard numbers... Looking at the Monivision 34" widescreen multisync CRT, I find they have a mask pitch of 0.36, described as Super Fine Pitch... (Sony tube?) which would give a full 1920 mask res.

No, that's 800 lines over a width that is equal to the screen height. Therefore the number of lines over the WHOLE width is 800 x 16/9 = 1422.This web page http://members.aol.com/ajaynejr/vidres.htm been posted on this forum numerous times - It is many pages and REALLY does know what it is talking about Traditionally, "lines of resolution" is correctly measured across the largest circle that fits in the space you are talking about. However some advertisers exaggerate using the entire screen width or using some electronic formula that only covers part of the circuitry. Modern standards stating resolution or screen dimensions in "pixels" (dots) reflect the entire screen width or height. I guess if it doesn't suit your argument it doesn't matter what anyone else thinks.

Thanks, RSawdey.
I wonder why manufacturers won't talk about dot pitch for HDTV?
Computer monitors that are CRTs consistently advertise it.

Measuring a width that is the same as the height of a biggest fit circle is the SAME as the height of the screen. Basic geometry, all diameters of a circle are equal. This essentially 'normalizes' the horizontal & vertical values so they are easily compared... square pixels will have these numbers equal. So your 800 lines are distributed across 9/16 of the screen. To find the full 16/16 of the width, multiply by 16/9.

Dot pitch and mask pitch are terms that only apply to CRTs... plasma doesn't have a mask... fixed pixel displays always seem to be reported in pixels, CRTs rarely.

I think I know the answer to my question as to why the CRT HDTV manufacturers hide the dot pitch information. They are probably afraid that people will learn that many of their "HDTV" sets cannot yield the full HDTV resolution.

does what you say about the TV having only 800/1442/whatever number (in any case, one thats less than 1920) pixels across, but yet 1080 lines up to down mean that the TV has rectangular pixels that are one-third-again/twice/however as wide as they are tall?

A better example of non-square pixels are the EDTV+ plasmas with 1024 x 768 pixels in a 16:9 screen... these pixels are each 4:3 aspect, instead of square, costing the viewer 33% of their horizontal res.

Either CRT mask pitch or horizontal sweep electronics speed can limit horizontal res, giving de facto non-square pixels.

The Sony 30XBR960 & 30XS955 has 1401 lines across?

The 1080i number is VERTICAL resolution... horizontal res may be called out as pixels of res, but that is 'per vertical height'... so TOTAL horizontal pixels will be the number times 16/9. Not true--my Sanyo HDTV 1080i only can display about 800 horizontal pixels--far short of the 1920 required for "true" 1920x1080 resolution.

What Sawdy said was 100% accurate. If the manufacturer says a unit has "800 lines horizontal" than you would multiply that by 16/9 == 1422 pixels from one edge of the screen to the other.

does what you say about the TV having only 800/1442/whatever number (in any case, one thats less than 1920) pixels across, but yet 1080 lines up to down mean that the TV has rectangular pixels that are one-third-again/twice/however as wide as they are tall?

A CRT is analog. It uses "waves" with up and down transitions to represent an image. Although a CRT might be receiving the full 1920 across image, its electronics might be poorly-designed such that it can only display 1442 distinct points. Anything smaller than 1/1442 size would disappear into a blur.

It's similar to how a VHS recording will be blurry. Anything smaller than 1/320 the VHS can not display.

There's more to it than that. The CRT tube itself has a coating of phosphor dots (triads of red, green and blue) and either a shadow mask or aperture grille (both have openings that allow electrons through to excite the proper phopshors while blocking electrons aimed at the other phosphors).

The fineness of the phosphor dots (size and density) and the fineness of the holes in the mask/grille (size and density) are primarily what determines how small a spot can be reproduced by the screen and therefore the ultimate resolution of the screen.

Then there's another level of confusion. All DTV formats are defined as a matrix of pixels. A 1080i signal will indeed try to draw 1920 horizontal pixels per line. The mask and phosphors aren't fine enough to reproduce the pixels accurately, but since the pixels are not physically aligned with the mask/phosphors in any way, it's possible for a phosphor to be excited by electrons from more than one pixel and to respond differently from one side of the phosphor dot to the other. This allows a CRT to appear to have more resolution than what is dictated strictly by the fineness of the mask/phosphors.

Thanks. Boby, for clarifying that. It always seemed to me that the CRT not only has better blacks and color, but their resolution, considered in a pixel sort of way, was just as good if not better as fixed pixel TVs that seem poor in color and blacks.

Indeed, although psychologist say we discriminate objects primarily by color/light/dark, and not often by the fineness of the edge of an object, I still thought I saw extraordinary resolution in the sense of fine edge detail of every object on my CRT. Now you have explained that.

For if each individual phosphor dot can illuminate different colors, for instance, well we are dealing with very good resolution, meaning it looks real, that doesn't depend on fixed pixels. Or the necessity of a massive number of pixels, which in fact we are far from for TVs even if digital still photography has greatly improved.

In fact, I wish I could find the source I read that stated that one phosphor dot is roughly equivalent to three or more fixed pixels on an LCD. Shouldn't one call the phosphor dot a dynamic pixel capable of multiple subtle color and tone, well, much like reality? Going to take a lot of pixels to do that on a TV. Don't think we are close.





There's more to it than that. The CRT tube itself has a coating of phosphor dots (triads of red, green and blue) and either a shadow mask or aperture grille (both have openings that allow electrons through to excite the proper phopshors while blocking electrons aimed at the other phosphors).

The fineness of the phosphor dots (size and density) and the fineness of the holes in the mask/grille (size and density) are primarily what determines how small a spot can be reproduced by the screen and therefore the ultimate resolution of the screen.

Then there's another level of confusion. All DTV formats are defined as a matrix of pixels. A 1080i signal will indeed try to draw 1920 horizontal pixels per line. The mask and phosphors aren't fine enough to reproduce the pixels accurately, but since the pixels are not physically aligned with the mask/phosphors in any way, it's possible for a phosphor to be excited by electrons from more than one pixel and to respond differently from one side of the phosphor dot to the other. This allows a CRT to appear to have more resolution than what is dictated strictly by the fineness of the mask/phosphors.

The eyes have more black-n-white receptors than color receptors. As a result the eyes can see the black-n-white portion very clearly, but the color portion poorly. That's why Luminance resolution on a 1080i HD signal is 1920x1080, but the Chroma resolution is only 960x540. The fineness of the phosphor dots (size and density) and the fineness of the holes in the mask/grille (size and density) are primarily what determines how small a spot can be reproduced by the screen.... Well yeah. Obviously an old CRT with only 720x480 phosphors is not going to display anything higher than that.

My point was: Even if you have a phosphor layout of 1920x1080 that's no guarantee you will see it on screen. If the electronics are bandwidth-limited to only 18 megahertz, you will get a "blurring" effect, and only see ~1000 across. Not 1920.

And then I compared it to a VCR:

A VHS tape may receive a 4 megahertz 440 edge-to-edge picture, but its internal electronics can only handle 3 megahertz. Thus the VCR will show a "blurred" image that is only 320 edge-to-edge.

What you say is true, but mostly theoretical as there are no consumer CRT tubes that have anywhere near 1920 x 1080 phosphor triads or anywhere 1920 x 1080 holes in their mask/grille. If someone were crazy enough to build one, they would certainly use high-bandwidth circuitry to support it, or it would be a huge waste of money and effort.

BTW, new CRT's aren't much better than old ones, except for the Sony Fine Pitch tubes which are no longer made--and even then, they still weren't capable of resolving all of the resolution of a 1920 x 1080 signal. Despite that, even a CRT with 720 x 480 phosphor triads would still be able to display more than 720 x 480 pixels due to the "multiple pixels per phosphor" effect.

It's important to realize, though, that the phosphor would not accurately reproduce the information supplied by multiple pixels, as there would be an interaction between the pixels, both of luminance and therefore chrominance as well, so the pixels would not be clearly delineated and the actual pixels themselves would be somewhat distorted by their interaction, as well as the masking effects of the mask/grille.

That doesn't mean CRT's look bad, just that they don't do great on a standard resolution test. Their black level, contrast, vividness (intensity and saturation) of color and super-fast response make them better than most other types of display, but their limited screen size, large size and weight and manufacturing/shipping/reliability issues, together with lower resolution, means CRT's are pretty much doomed. If you like 'em, buy 'em while you still can.

Here you go . . . .

The specs on the Sony Pro 20" CRT monitor that is the standard throughout the world - just under $14,000

Notice they do not give specific resolutions

http://bssc.sel.sony.com/BroadcastandBusiness/DisplayModel?m=10007&p=8&sp=20073&id=80821&navid=master_series_video_monitors

Too expensive? No problem . . how about a 14" for $6,235?

http://bssc.sel.sony.com/BroadcastandBusiness/DisplayModel?m=10007&p=8&sp=20073&id=80824&navid=master_series_video_monitors

Wow an old thread. I don't know if the thread question was answered, but I believe the correct answer is the Sony 30" Super Fine Pitch displays, the KV-30XBR910 and KD-30XS955. I don't believe Sony ever made any other 30" display with the tube and don't believe any other manufacturer equaled the resolution of that tube. I wouldn't however recommend buying the Sony 30" CRT HD display, although I still love mine, I would certainly buy something different today or last year or the year before for that matter.

I believe the Super Fine Pitch displays were made in the US and at great expense. I would say it was sort of a final technical achievement statement for a dying breed. Whether or not profits were the outcome isn't clear, I doubt it, but the achievement in terms of picture quality from that old technology was impressive to me.

Chris

The 1080i number is VERTICAL resolution... horizontal res may be called out as pixels of res, but that is 'per vertical height'... so TOTAL horizontal pixels will be the number times 16/9.

After reading this thread, I think I now understand why 76 people have viewed my post without one reply. My question was,What are the alternating dark and light horizontal stripes across the entire screen on my Sony 50" Wega?Lines of resolution dip sh--!:oHowever,
I never noticed these stripes to be as wide as they are now.When I switch to an HD channel they do get a lot narrower but they're still annoying.Sorry if I'm off topic.

Which 30 inch CRT HDTV has the most horizontal lines of resolution? :confused:

The one with the finest Dot Pitch.

The Shadow Mask becomes the limiting factor in H. Res.