Film-Tech Forum ARCHIVE: LCD-Based Rear-Projection TVs

This is topic LCD-Based Rear-Projection TVs in forum Film-Yak at Film-Tech Forum ARCHIVE.

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Posted by David Stambaugh (Member # 1102) on 12-06-2002, 08:42 PM:

Anyone here taken a close look at any of the new LCD-technology rear-projection TVs, like the Sony KF-50XBR800 ? Cheaper than plasma, supposedly no issues with image burn, and no convergence problems. Curious if anyone has taken a critical look at something like this. So far I can't find any dealers in Eugene that have one on display. The only thing that bugs me about this Sony is it looks like it converts everything to 720p, even 480p DVD. Might be some artifact issues with that. Street price looks to be ~$3500.

Posted by Bobby Henderson (Member # 840) on 12-07-2002, 02:03 PM:

That Sony monitor looks pretty cool, but I would have to see one in person to be able to make any judgment on picture quality.

The image burn thing is an issue with some widescreen TVs and it is nice to see products finally coming out that address the issue. Many with widescreen TVs have to watch 4:3 ratio broadcasts either stretched out across the set or zoomed in to avoid the black/grey bars burning in on the sides of their monitor. With this set I suppose it will not hurt anything to watch all programs in their proper aspect ratio.

Still, I don't think I would buy the product. The pixel count (1366 X 768) is better than most any plasma screen, but it still is not good enough. I don't know why the big screen makers cannot seem to get any flat screen TVs made with true 1920 X 1080 pixel resolution. That is what they need to do to properly resolve true 1080i HD.

To compare, look at the high end computer monitor market. Apple's Studio Cinema Display 23" widescreen computer monitor has a 1920 X 1200 pixel UXGA-W display.
http://www.apple.com/displays/acd23/

Viewsonic has a 22.2" flat screen monitor boasting a whopping 9.2 million pixels! The QUXGA format is 3840 X 2400 native pixels.
http://www.viewsonic.com/products/lcd_vp2290b.htm

The big screen TV makers need to kick things into another gear and get their pixel counts up. Viewsonic's VP2290 desktop monitor packs enough pixels to nearly fit a full 4,000 line CGI rendering. That's far, far above anything any standard HD set can do. The least thing the flat screen TV makers can do is hit that native 1920 X 1080 pixels mark.

Posted by John Pytlak (Member # 331) on 12-07-2002, 02:32 PM:

1280 x 1024 pixels just doesn't sound that impressive anymore, does it?

Posted by Mark Gulbrandsen (Member # 72) on 12-07-2002, 03:04 PM:

I agree totally with John on his statement. The best rear screen set going right now is the Mitsubishi DLP job. Simply amazing to say the least! Now if we could get Kodak to put their hi rez ILA system into a rear screen set we'd have the ultimate!
For every day use I still prefer a CRT set even with its tendency to drift in adjustment slightly over time. Apparent higher resolution, and no artifacts.....unless the sets D to A's are adding anything in. I'd bet that the CRT's would last through a half dozen lamp changes in an LCD rear screen(anywhere from 1800.00 to 3,000.00 worth of lamps!). Average cost to re-crt a set is about 1200.00 to 1800.00. Also, Joe's TV can come and fix it in your home.....but can they, and are many shops familiar enough to repair an LCD set in your home? Moving a big screen, even its guts into the shop is a chore in itself.
Mark

Posted by Paul Mayer (Member # 355) on 12-07-2002, 03:13 PM:

Also, LCDs still don't make blacks black enough, not for me anyway. CRTs still reign supreme in that area.

Posted by Ian Price (Member # 14) on 12-07-2002, 03:17 PM:

Mitsubishi WD-65100 65" HD DLP Rear Projection Television also has 1280 x 768 rsolution. I'll bet the DLP looks better than the LCD though.

I want a 50" flat screen for less than $2,000 that is HDTV native.

$7,795.00 [Eek!]

Posted by Mark Gulbrandsen (Member # 72) on 12-07-2002, 05:09 PM:

Paul,
Many CRT based TV's have a DC restoration circuit in them to aid in proper black level. Even my old 1946 RCA 621TS has it. Ya ought to see the pix on that set!! Sharp as a tack and video bandwidth flat out to 5 mhz! Pictures are sharp as a tack.

Still in any TV there is no true "black" Actual black level is 7.5 units IRE or thereabouts with 100 units being full modulation, or max white level.
Mark

Posted by Paul Mayer (Member # 355) on 12-08-2002, 01:47 AM:

While it's true that black level in US NTSC is 7.5 IRE above blanking, I was talking about the ability to adjust a CRT's screen levels so that there is no discernible light output (beam just barely cutoff) when 7.5 IRE is displayed, especially in a dark room like a theatre, or the video shading area in a production truck. Current LCDs just can't get opaque enough to do that; DLP and I-DLA are better, and like Mark indicates, CRTs rule in that area! [thumbsup]

BTW, the use of setup (differentiating picture black level from blanking level) is not universal in NTSC countries. Japan for instance, does not use setup--picture black occurs at blanking or 0 IRE. Gives them a few more IRE dynamic range to play with and creates a small pain in the butt for me since I have to reset my monitor's black level every time I want to watch a Japanese Region 2 DVD. Such is the life of a video elitist! [Roll Eyes]

Posted by Bruce McGee (Member # 131) on 12-08-2002, 07:53 AM:

What is the key light-source on these LCD projection sets?

I used to use a nice xenon LCD projector for computer graphics until last year. It used to go through xenon lamps like nothing.

What will owners do when the LCD panels become defective? Example: color spots in the image, etc.

Our xenon had a convergence problem that the builder could never get straight. Close, but not perfect.

My 1960 21" RCA color TV (chassis CTC-10E) has excellent DC restoration, and after I replaced all the caps, it no longer blooms on white images either!!!

Posted by Mark Gulbrandsen (Member # 72) on 12-08-2002, 09:32 AM:

Usually LCD sets use either Metal Halide lamps and many come with an integral reflector which is prefocus and adjusted. Some use xenon lamps and these are more expensive.
Mark

Posted by Steve Scott (Member # 630) on 12-08-2002, 08:33 PM:

Panasonic's 42" LCD projection monitor is no match for DLP, the sheer brightness of the DLP monitor, especially in wide open rooms is far ahead of LCD. The LCD projection TV also has issues with switching between 480p and 1080i modes. Once you set it to one, you basically have to initialize the monitor to change that setting.

Posted by Bobby Henderson (Member # 840) on 12-08-2002, 11:08 PM:

But with DLP maxing out at 1280 X 1024, why bother? It doesn't meet the requirements to show a ful 1080i image.

I'm sure Texas Instruments has to be encountering some frustrating R&D problems with their micromirror technology. If not, they surely would have come up with significantly higher rez chips and with the higher rez being in native 16:9 form.

Posted by David Stambaugh (Member # 1102) on 12-20-2002, 09:23 PM:

Panasonic LCD Rear-Projection TVs

I saw the 40" version of the Panasonic yesterday at Circuit City. They had a high-def video feed running on all the sets on display, which made it easy to compare this one to conventional CRT-based sets, but it only showed video-sourced material, no film, and of course no standard-definition material. From a normal viewing distance, the HDTV video was pretty impressive. I could easily pick out detail in the LCD's picture that was missing on other sets. Color accuracy seemed good; very bright, absolutely no "ringing", ghosting, convergance problems, or other anomalies associated with CRTs. No noticeable geometry errors. It also had less overscan on all sides than the other sets next to it.

On the downside, it seemed like fast motion was a little blurred, as if the set's video processor was having trouble keeping up. This wasn't horrible, but I did notice it. Blacks were not completely black (as expected), but were pretty good. I wanted to dink with the picture controls to see if I could improve the blacks at all, but the remote wouldn't work. As with all r-p sets, if you get too close to the screen, you get hot-spotting, but at a reasonable viewing distance, the screen illumination seemed uniform, and image quality was extremely sharp across the entire screen.

I also tried to compare the LCD set to plasma, but the plasma sets were on the opposite side of the showroom. But it seemed like the LCD set was sharper and brighter than plasma.

Anyway, my 5 minutes spent looking at this set convinced me that this would be worth taking a closer look at...

Posted by Mark Gulbrandsen (Member # 72) on 12-21-2002, 06:56 AM:

Dave,
LCD's always have that time lag to some extent. They have gotten better, but there will always be some of it. Its an artifact of the LCD panels themselves, not the circuitry. Old LCD's were REALLY bad at this! If you watch alot of sports then LCD is definately not the way to go.
Mark

Posted by David Stambaugh (Member # 1102) on 01-06-2003, 11:29 AM:

Update: Circuit City has the Sony mentioned in the 1st post in this thread. With high-definition material, it's the best TV I've ever seen. Extremely bright, crisp, clear, yadda yadda. It blew away everything else on their showroom floor. Blacks were surprisingly good. OTOH, with a standard DSS feed of CNN, it looks like total CRAP! The standard DirectTV picture looked like a mosaic. In other words, with a monitor this good, it's definitely garbage in - garbage out. I plan to go back and check it out with DVD material.

Anomalies: They were running a high-def signal into it, happened to be a tennis match. Definitely some blurring of fast motion. But relatively static images are unbelievably detailed. Also, it had a pixel stuck on (blue one). Wasn't really visible from a normal viewing distance, but was easy to pick out up close. I would want to find out whether that's considered a defect or not under the warranty. For $4000 there should be ZERO bad pixels.

Posted by John Pytlak (Member # 331) on 01-06-2003, 12:27 PM:

David Stambaugh wrote: "Also, it had a pixel stuck on (blue one). Wasn't really visible from a normal viewing distance, but was easy to pick out up close. I would want to find out whether that's considered a defect or not under the warranty. For $4000 there should be ZERO bad pixels."

I guess if there were any visible "dead pixels" out of the box, I'd return the monitor immediately. The real question is what the failure rate over time will be. Unlike a digital camera, where you can interpolate to "hide" dead pixels, a failure of digital display pixels is there for all to notice, especially when stuck in the "on" position. [Frown]

BTW, did anyone notice the horrible digital artifacts on the Fox Network coverage of the NFC playoff game between the NY Giants and SF 49'ers yesterday? It was almost unwatchable at times, with severe "jaggies" and strobing.

Posted by Mark Gulbrandsen (Member # 72) on 01-06-2003, 07:32 PM:

Dave said "it's definitely garbage in - garbage out"

I wonder if an the Panasonic LCD set has the equivelent of line doubling built...or if that can even be done......Judging by what you stated I don't think it does that......
My Mitsubishi 50" HDTV has built in line doubling and allowing even so so looking video to look a bit better than it might otherwise. I've always liked this feature about the set. The biggest percieved difference between NTSC, and HDTV is only in apparent resolution....and there are still no visible scan lines at any format.
Mark

Posted by Bobby Henderson (Member # 840) on 01-06-2003, 09:19 PM:

My father has one of those big Mitsubishi sets. I agree, the stock line doubler does a pretty credible job with NTSC material --IMHO, noticeably better than how a lot of flat panel screens treat NTSC.
Many flat screen TVs on the market, with perhaps the exception of the really expensive models, leave much to be desired in terms of image quality. Flat screens have a long way to go.

Posted by David Stambaugh (Member # 1102) on 01-06-2003, 09:37 PM:

I have a Sony RPTV with their 1st-generation DRC line doubling, Digital Reality Creation. The idea is it not only does line doubling, but it's supposed to supply what it thinks is the "missing information" for the image being uprez'd. DRC is definitely a mixed bag. If you feed it a good, clean signal, it does a pretty good job. If you feed it something nasty like bad VHS or the worst of the DSS stuff, it looks pretty bad.

Mark, the set I was commenting on is the Sony KF-50XBR800. (I did mention a Panasonic, but the Sony seems to blow it away.)

Bobby, if you have nothing better to do, you should check out that Sony if you can find it on display someplace. [Smile]

It's not perfect, but it's very very good. Be fair to it -- judge the picture from a normal viewing distance. [Wink]

I'm not going to rush out and buy one, especially given that I haven't seen it with any film-sourced material or DVD yet. But on HD video, it's pretty sweet. [Cool]

Posted by Mark Gulbrandsen (Member # 72) on 01-06-2003, 10:08 PM:

Will check it out since both Circuit City, and Worst Buy are within a mile of my house. I don't think the Mitsubishi line doubler does the same thing the Sony's is doing. The Mits doesn't try to replace missing info....and that can't really be done properly except in DTV with error correction. The Mits is just always running in line double mode for everything. The lack of scan lines is really nice. Never have seen VHS on this set as I don't own one. Its pretty much obsolete in my book. I have analog Cable(how bout that Steve Guttag?), DVD, and Laser Disk feeding it. As well as the Mitsubishi HDTV tuner which is a wonder of computer chips and other stuff in and of itself......

I did have one problem once with the Mits after about two years...it ate a deflection yoke and took some transistors out when it went. Luckily the CRT's have a protection circuit that really works as there were no burns in the CRT's at all once I got it going again.

Mark

Posted by David Stambaugh (Member # 1102) on 01-12-2003, 08:17 PM:

Toshiba has a 57" LCoS (Liquid Crystal on Silicon) rear-projection [dlp]

with true 1080p resolution (that's 1080p, not 1080i [beer]

) . Uses 3 1920 x 1080 chips. Priced at $9000 [eyes]

Toshiba LCoS

Posted by Daryl C. W. O'Shea (Member # 1303) on 01-12-2003, 08:30 PM:

David Stambaugh wrote: "Also, it had a pixel stuck on (blue one). Wasn't really visible from a normal viewing distance, but was easy to pick out up close. I would want to find out whether that's considered a defect or not under the warranty. For $4000 there should be ZERO bad pixels."

Sometimes I get a little piece of dirt stuck to my NEC LCD display that makes it look like a blue stuck pixel. Maybe the store display unit was dirty? Then again, with kids slapping their paws all over it, I wouldn't doubt the existence of busted pixels.

Posted by David Stambaugh (Member # 1102) on 01-12-2003, 08:40 PM:

Bad pixels (may be stuck on or off) has always been a nuisance issue with LCD displays. I've seen many older notebook PCs with stuck pixels. A few of the more reputable sellers of used notebooks on eBay will tell you if what they're selling has any stuck pixels. I read somewhere that some manufacturers of LCD-based displays used to have a written policy as to the percentage of pixels that could be bad on a display while under warranty before they would consider it defective. Don't know if that's still true.

Anyway, this Sony LCD set definitely had a bad pixel -- wasn't dirt or anything like that.

Posted by Paul G. Thompson (Member # 655) on 01-12-2003, 09:23 PM:

While walking through Sears and Costco today, Sears had one of those Plazma screen TV's for 7,000 bucks. I was not impressed with it. The closer I got to the screen, the worse the picture "fell apart."

At Costco, a HDTV set was on display. The picture looked good, but I did notice that the viewing angle was critical, and the fall-off was almost as bad as watching a movie on a silver screen.

Naturally, there is no comparison about picture quality with the old scanning raster system as we know it form the days of old.

However, I cannot justify spending 7000 bucks to watch clearer commercials or box office flops on DVD or VCR.

Posted by Bobby Henderson (Member # 840) on 01-12-2003, 11:39 PM:

The Toshiba LCOS based set is a step in the right direction. I personally believe any flat-screen TV maker should not be allowed at all to use the term "HD" or "Hi-Def" on any TV set not equipped to show 1080 X 1920 native pixels in its display. That is a very basic standard bar all of the manufacturers should meet.

What I am asking for is perfectly reasonable as well, considering the TV manufacturers want people to hook their computers and gaming machines up to these large displays. I'm not doing any kind of computing at all on a screen that shows less than 1600 X 1200 pixels. No way. Not negotiable. 1280 X 1024? Go back to the drawing board.

1920 X 1080 native based displays should only be a starting point as well. I strongly believe the resolution specs should be upped by a great degree. If "convergence" with computer hardware is an ultimate goal, then display standards like QUXGA 3840 X 2400 would be perfectly reasonable for any large, high end monitor. HD Video display is not the only application. How about viewing digital camera photos on these monitors? Affordable cameras have surpassed the 3 and 4 million pixel mark. Higher end units have been marching past the 6 Mpixel level. We will see affordable digital cameras with 10Mpixel image capture in the next 2 to 5 years. CCD imagers and 3D accelerator chips seem to be the most rapidly improving types of computer components in the entire industry. The technology in video monitors is going to have to keep up.

Posted by John Pytlak (Member # 331) on 01-17-2003, 03:39 PM:

I agree, 1280 x 1024 pixel resolution is old news.

Kodak announced a 14-megapixel camera at PhotoKina that is very competitively priced (likely less than $5000):

Kodak DCS Pro 14n Digital Camera

http://www.dpreview.com/news/0209/02092304kodakdcs14n.asp

http://www.bjphoto.co.uk/cms/words/news_and_news_features/75.shtml

Posted by David Stambaugh (Member # 1102) on 03-18-2003, 02:52 PM:

Widescreen Review's review of the $6000 Sony KF-60XBR800 says the manual for the set claims that stuck pixels are "a structural property of the LCD panel and not a malfunction." [eyes]

Posted by Mark Gulbrandsen (Member # 72) on 03-18-2003, 10:00 PM:

"At Costco, a HDTV set was on display. The picture looked good, but I did notice that the viewing angle was critical, and the fall-off was almost as bad as watching a movie on a silver screen."
______________________________________________________________
Paul, Thats because these sets all use some sort of lens thats part of the screen. Not quite fresnel, but on that order. They have gotten ALOT better than they were back in the late 70's early 80's!! Back then you had to be seated right in front of it.

David....Stuck pixels....I think ALL LCD panels, and DLP, or wjhat ever is used for that matter are going to have at least some percentage of bad ones. But I think the term structural property is only a lame term devised by the Sony marketing department to cover it all up. If customers were aware they were getting bad Pixels would they buy them???? Remember....Sony, No Baloney!

Had a long talk with a projection TV expert the other day.....LCD vs. CRT and we both came to the conclusion that CRT is still far and away more practical for home use and will give the best results. Consider for instance how many metal halide lamps one would use in 7 years. These lamps are in the 500.00 to 750.00 range for alot of decent LCD projection sets, but CRT's for even a decent Barco CRT set is still only 300.00 each. The original set of CRT's should last around 7 years by themselves if image burn in is not a factor in its use. CRT's also have far greater contrast ratio range and much better resolution, especially horizontally. Better colorimitry for now too. With a line doubler as is integrated into many sets these days scan lines are practically unnoticable. While pixels are still visible. Granted other types of displays are getting better the CRT is still outpacing the others in most parameter departments, and may continue to do so for quite some time.
Mark