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Discussion Starter · #1 ·
Greetings. For the last couple of weeks, I have been trying to figure out my options and perhaps nail down a choice for the visual portion of a hypothetical living room setup to replace my current one. The journey has led me from large direct-view TVs to rear-projection TVs to CRT-based front projectors and finally to DLP-based front projectors, which until two hours ago I was certain were the end of the trail.


That was before a friend of mine stumbled upon a passing word about something called LCOS - "Liquid Crystal On Silicon." I say 'stumbled' because that's the best description of how we ended up discovering this format for ourselves. Information about its very existence is so scarce.. Well, let's just say that I didn't even see one SINGLE post about it HERE (and still don't), much less in other related venues, and that's frankly a real mystery.


What I know: It's LCD-based, but aspects of its manufacture enables high resolutions for unusually low prices. It has some aspects of DLP technology. Supposedly, the image is good (how good remains to be mentioned). There seem to be no issues with poor brightness levels. JVC makes a proprietary rendition of the technology, which they call "D-ILA", and the differences / advantages of theirs over regular LCOS are very unclear.


What I don't know:


1) How good is the image? Witness:

http://www.extremetech.com/article/0...=4&ap=5,00.asp


A third of the way down the page, they show a comparison between (regular) LCD and DLP. The LCD image showcases the sort of crummy image which turned me off of front projectors for the past ten years. The DLP image still has an obvious grid (picky or not, any cheap direct-view TV could do better) but it is at least a dramatic improvement over the LCD. These are examples of "bad" and "good". How does LCOS fare?


2) What does JVC's "D-ILA" have over "LCOS", other than a completely different name? If anything.


3) What are the hidden drawbacks? As always, with high-end equipment, there are going to be little issues which all high-end enthusiasts learn to become blind to. CRT FPs are dark and require 24/7 calibration. LCD FPs suffer from a relatively crap image and perpetual issues with dead pixels. DLP is still a bit pricey, has comparatively poor contrast (a-la the blacks), and even suffers from a lovely rainbow effect and tearing artifacts. How about LCOS?


Right off the bat I suppose one could expect to get about one dead pixel a week.


4) What are the available models and are there any "clear winners" the way there can be said to be with DLP technology? (Sharp 9000 leaps to mind)


5) Why is talk of this technology, or the projectors which feature it, so.. utterly nonexistent? (I'd say scarce, but that word implies that there is some talk to be found)


6) Thought I'd again ask what are some of the better low-cost places to shop online :p


That'll do for now. I'll continue my research as well. Thanks in advance.
 

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I won't attempt to answer all your questions but two projectors, the Dukane being a clone of the Hitachi spring to mind using LCOS. They are the Hitachi CP-SX5500W and the Dukane ImagePro 9115. You'll find lots of debate and information on them here if you do a search.


Regards,

Glenn
 

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Just one thing that I will point out, many threads have been posted about the Hitachi 5500 which is a LCOS projector and has received quite a bit of critical evaluation. Then there are the JVC models, G10, G11, G15, G150(Home Theater model), all have several posts about them going back, there is a current thread about the New JVC 150 running. From your post is seems there are several misconceptions about FP and I am not one to go into in depth with answers since so many more qualified have answered before.


I would suggest doing a search on Hitachi, and G10 etc. and you will learn far more. There is also a post by Milori in which various screen door similuations are pictured representing the three current technologies under different scenarios (anamorphic lens, depix lens).


Happy reading :)
 

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Colmino,


I see you are relatively new to this forum. There's an awful lot of information here on D-ILA and LCOS.

A while back, it seemed we didn't discuss anything BUT D-ILA.


First - some definition of terms. LCOS is the generic name for the technology. D-ILA is JVC's [ the originator ]

trademark name for LCOS. [ It's like "Kleenex" is a trademark name for a brand of "tissue". ]


1) Currently, D-ILA has the most resolution [ SXGA+ ] of any digital projectors out there. [ JVC also makes a QXGA PJ,

for commercial venues - but that's priced in the stratosphere.]


D-ILA / LCOS has the best "fill factor" which mitigates the "screendoor" effect and visible pixels. LCDs have the

worse screendoor. This is explained in one of Mark Hunter's aka "milori" posts:

http://www.avsforum.com/avs-vb/showt...threadid=95686


2) As above - "D-ILA" is a particular brand of "LCOS".


3) The main drawback to D-ILA stems not from the use of the

D-ILA/LCOS technology in the chip - but JVC's choice of lamp

technology. JVC D-ILAs use a Xenon arc lamp - which runs hotter than the UHP bulbs in most projectors. This is a

double edged sword - the higher color temperature means the D-ILAs have nice colors - but the greater cooling requirement

means the JVCs have more fan noise. Most D-ILA owners solve this by enclosing the D-ILA in a "hushbox", or by mounting

it behind the rear theater wall in another room. The latest offerings from JVC have reduced fan noise.


4) JVC currently makes the G15 and G20 models, as well as a new offering the G150. There are also the "M" models - but

that would be for the pros. The G15 is quite popular.


Hitachi makes a competitive model - the "5500"


5) D-ILA / LCOS technology may not have been discussed lately because we're "all talked out" about it. Honestly,

D-ILA used to be THE topic on this forum - so most of us know quite a bit about it. Tom Stites of JVC has also been

a frequent poster here - discussing all D-ILA issues. You might do a search on his moniker - "tstites".


6) One of the best places to shop online is our host on this forum - AVS Science.


Dr. Gregory Greenman

Physicist
 

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LCOS should have the best fill factor (in theory). LCD needs the place for the electronics, DLP needs the place for mirror movement. LCOS is reflective like DLP so the electronics can be behind the reflective surface, but there are ne moving parts, so it does not need that moving space


But the funny thing about the screen door effect is that other factors (not only the fill rate) such as focus, play a role. Look at these two pictures, same projector, different focus.
http://www.dilard.com/dilard/images/...LCDFocused.jpg
http://www.dilard.com/dilard/images/...DDeFocused.jpg


Like Morbius said, the discussions here run in waves, so just because there are not many threads on LCOS at the moment that does not mean that it was not dealt with in the past (or the future) at great lengths


It is not DLP that creates the rainbows, they happen because most DLP projectors use a single DLP chip and a color wheel. This means that at any point in time you only see one color on the screen, but the change happens so fast that to the brain (in the most part) it looks like one image with different colors (same way that the images change so fast that it looks like there is movement). It is also the reason that DLP projectors tend to be less bright (1/3 of the light is absorbed since at any point of time the color absorbs most of the color from the white light) LCD and LCOS projectors use three panels one for each color. The white light is split into the three primary colors and each hits a different panel. then the three images are recombined and sent as one image.
 

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Quote:
Originally posted by Colmino
Well, let's just say that I didn't even see one SINGLE post about it HERE (and still don't), much less in other related venues, and that's frankly a real mystery.
I just did a search on "lcos", and it found 450 threads.


A search for "d-ila" found 6882 threads!


Perhaps you weren't using the search tool correctly. You've absolutely come to the right place if you want to know more about LCOS/D-ILA technology (and to find people who are fanatically devoted to it!)


- Chris
 

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Discussion Starter · #8 ·
Thanks for the great responses, folks. I'm simply astounded by this forum's denizens.


You are correct, I hadn't made use of the search function. To be honest, after dealing with searches in other forums, I'd just jumped to the conclusion that I'd find more by skimming the (two) pages of topics with IE's text finder (believe it or not, this is usually the case). I will make use of the search function now. :)


AOTC. Loved it. Been literally years since I had that much fun at the theater. (LotR was marred by a soundtrack that was poor 90% of the time.)
 

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Discussion Starter · #9 ·
Well, after a bit of searching, I got a lot of answers, but there are still some lesser questions nagging me...


1) Projector noise.

a) > JVC D-ILAs use a Xenon arc lamp - which runs hotter than the UHP bulbs in most projectors. This is a double edged sword - the higher color temperature means the D-ILAs have nice colors - but the greater cooling requirement means the JVCs have more fan noise.


Is there a website out there which documents the noise levels (dB) from the various projectors out there? Or does somebody have the numbers handy? It sounds like D-ILA projectors are more problematic in this area than any other digital projector technology.


b) > Most D-ILA owners solve this by enclosing the D-ILA in a "hushbox"


Is there a faq available online for this option?


c) > The latest offerings from JVC have reduced fan noise.


Lacking specific numbers for noise levels from the various models, may I ask which models are the new ones which have reduced fan noise?


2) Since it's basically "good" old LCD technology, it is suspected (even anticipated) that one of the biggest drawbacks is dying pixels. I personally have yet to witness a LCD-based projector that did not have at least one dead pixel in it, and most of the LCD-based laptops I have seen had dead pixels as well.


But then, since the technology is a bit different, perhaps the problem is reduced. Anyone heard any stories about dead pixels in LCOS panels?


3) The alarming thing I read about recently is the possibility of burn in, resulting from improperly set COM voltages.


a) Is there a standard method for monitoring the COM voltages to determine if they've been improperly set?


b) I think I read that the problem can surface simply from electrical issues (DC voltages leaking into the projector rather than AC, or something along those lines). If one could prevent such issues, would that help? Are there any methods for doing this? (Like a nice UPS?)


4) 16:9. Any LCOS / D-ILA projectors which support this resolution without in fact doing so by displaying the middle 75% of a 4:3 box? The loss of resolution that sacrifice represents is just nonsensical.


Thanks again. My research continues. (There's a gargantuan FAQ thread with links to past threads.. pretty much all of which are dead, heh.)
 

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Hi Colmino,

1. (a) Fan Noise. Yes, D-ILA's are louder than most digital projectors and are on par with some CRT's. The number I've seen mentioned is 60 dB, but I haven't measured it myself. To me it sounds much like a bathroom fan, but it's a warm neutral "woosh" so isn't too distracting (unlike a whining hard drive or colour wheel).

(b) Lots of info in the forum.. try searching for "hushbox" or "WhisperFlow" in the title line.

(c) The new 150CL has reduced fan noise, to the point where a hushbox is not required. The G series all have similar fans. I'm not using a hushbox with my G10 and don't find it to be an issue.

2. Dead pixels. After two years my D-ILA hasn't developed any new dead subpixels, and I've seen only one report on the forum of a subpixel dying (and this forum has seen hundreds of D-ILA owners). So it seems that deterioration of the panels is relatively uncommon.


Some projectors are shipped with a couple of dead subpixels, but they are difficult to notice (mine has two on the blue panel). With a resolution of 1365x1024 these suckers are tiny. Plus a dead subpixel will only affect one of the three panels so only changes the colour of the pixel rather than killing it completely. Most dead subpixels are the "always-off" variety rather than "always-on" so aren't as bad you might think. Still, check with your dealer for their dead pixel policy.

3. (a) Burn-in. Extremely rare. It shouldn't be a problem unless the COM voltage is improperly set by the factory. If you have the projector calibrated you can have these voltages checked at the same time.

(b) The best prevention is to avoid static computer images for long periods of time. Even so, the latent image usually clears itself after a few hours.

4. 16:9 screens. The new 150CL has excellent controls for handling 16:9 screens, and for older D-ILA's there is a third-party application called Dilard which can be used to set the image placement and scaling parameters (plus tons of other nifty stuff like calibration and automation).


Yes, a 16:9 image takes up 75% of the 4:3 panel, but with a 1365x1024 panel you can afford to drop down to 1365x768 and still have a very high resolution image. If you want to use the full panel for 16:9 you can add an anamorphic lens like the ISCO II or Panamorph.


Cheers,

Dave.
 

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Discussion Starter · #11 ·
> Yes, a 16:9 image takes up 75% of the 4:3 panel, but with a 1365x1024 panel you can afford to drop down to 1365x768 and still have a very high resolution image. If you want to use the full panel for 16:9 you can add an anamorphic lens like the ISCO II or Panamorph.


One question in response to this. The resolution for the various JVC projectors is 1365x768. This seems odd to me. Granted, it's a close approximation of 4:3, but ultimately the fact is it's impossible to have mathematically "solid" scaling from 640x480, 1024x768 etc to a horizontal resolution with an odd number like 1365.


It's important to realize that I'm not for example overlooking the probability that a high resolution like 1365x1024 would begin to make the accuracy of one or two pixels moot. The point can best be explained by example. If you take a 640x480 image and scale it to 1280x960, the transition is easy: you just double each pixel horizontally and vertically (and throw in a filter). Similarly, downscaling from 1280x960 to 640x480 is easy. But throw this "solidity" out of whack, by for example giving the scaler the task of dealing with a 636x477 image or something, and the result doesn't look so hot. At best, the image will suffer some blur. Anyone who uses non-conformant resolutions on a PC with an LCD monitor would know what I'm talking about.


I guess a good question on this subject would be: How does (or how can) the JVC projectors handle 1280x1024 video from a PC? It's 4:3 on the monitor, of course. Does the JVC have the option of modifying its horizontal projection width to display 1280x1024 without scaling it to fit 1365x1024?


---


More confusion on the JVC front.


What's the difference between the G15 and the G15U? (Or are they the same exact thing?)


Regarding the same model(s), I saw that they could be had for near as low as $8000. This was mentioned in a post made almost exactly one month ago. I assume the price has either stayed or dropped a bit since then. But preliminary searches aren't surfacing prices anywhere near that.


I know I'm doing something wrong. Not looking in the right places. I sent off an email to AVS, though I despise the necessity of doing so, as it smacks of the times I enter the local Ultimate Electronics and witness the commission salesman-to-customer ratio of 2:1. Are they seriously going to have the best price? I understand they had some sort of issues with JVC in the recent past.


And lastly, something I'd been taking for granted but my brother wishes to know up front: Would the G15 be able to handle 24fps progressive (I basically mean film from DVD) as actually 24fps progressive? If so, what resolutions? If not, does it at least do a reasonable job of 3:2 pulldown?


Thanks as always. I hope the answers to these questions are proving helpful to other people, too.
 

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Discussion Starter · #12 ·
Well. My journey came to a crashing halt recently when I discovered 1) the lifespan of the bulbs used in JVC D-ILA projectors and 2) the cost of replacement bulbs. An extra ~$5,000 per year to keep an $8,000 projector running is just not going to work. This discovery set my journey all the way back, option-wise, to the time during which I was considering a really large direct-view TV, because such an option is simply more agreeable to me than any non-LCOS projection solution.


But there may be light at the end of the tunnel, as at least two of the other LCOS projector manufacturers use UHP lamps in their models.


The specific models are the Hitachi SX5500 and the Vivid Red from Christie Digital.


I will save the rest of this post for a new thread, which I feel must be created due to the true lack of information and the ambiguity of this thread's title. But suffice to say that I must now abandon JVC as an option. And frankly, I'm relieved. They can take their pricing schedule "based on performance, not manufacture cost" and choke on it. (But that's just my opinion)
 

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What are your assumptions about bulb cost leading you to your $5,000/yr number. That seems way to high from what I've read here?


Call Jason at AVS to discuss pricing. You will find is very different than posted list prices. Whats your problem with performance based pricing? Have you never lusted over a SUV?
 

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Hi Colmino,


JVC is actually the one using a standard 4:3 resolution at 1365x1204, it's the computer resolution of 1280x1024 (5:4) which is non-standard! Yes, the D-ILA has an option to either display 1280x1024 at native res or to scale up to 1365x1024. The best option is to use a custom computer resolution of 1360x1024 for perfect 1:1 pixel mapping.


Scaling quality is another topic onto itself which can fill many pages. Try searching the HTPC forum or video processor forum as it's been very well covered here. DVD resolution is 720x480 so needs to be scaled in some way regardless of your projector. Some PC graphics cards (like the Radeon) have excellent bicubic scaling algorithms and can match the native resolution of the projector for a detailed image which is virtually free of artifacts. Using an HTPC (Home Theatre PC) as a DVD player is very popular around here since it provides exceptional video quality and an all-digital path at a reasonable cost.


G15 is shorthand for the DLA-G15U. The "U" means it is the model with the standard 2-3X zoom lens. There are other G15 models with different lens, but I would avoid these unless you have a rear projection screen or a specialized installation.


I saw a few used G15's in the AVS Classifieds Forum for around $8000. AVS occasionally does "power buys" where a group of projectors is ordered at a discount. The last one almost fell apart due to internal miscommunication at JVC, but I think those issues have been sorted out now. AVS is the highest volume internet dealer of D-ILA's so their prices should be competitive.


The question of progressive 24fps goes back to the HTPC. A software DVD player does 3:2 pulldown to re-create the progressive frames, and then the video card can scale up to the projector's native resolution and output at any refresh rate. By choosing a multiple of 24 (like 48Hz or 72Hz) each frame is displayed exactly 2 (or 3) times so you get perfect, liquid-smooth, 24fps motion. The 150CL can directly accept 24fps, but so far no one has tried this (and you would need a Teranex as a source!).


Your bulb cost estimate seems high. The 150CL has a lamp power control option which extends the bulb life to 2000 hours and the bulbs can be re-lamped by Atlas Lighting for around $500. Try searching the forum for "Cermax".


Cheers,

Dave.
 

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Geez, isn't it interesting how someone using this forum to look for this specific information could come to some of these conclusions?


I was about to contribute to the thread along the lines of some the other contributors, but I quickly saw that the thread was going nowhere.


No flaming intended, but Colmino, it seems to me that you should probably go with a RPTV or FP CRT.


A well calibrated DiLA is probably the pinnacle of digital front projectors. A lot of forum members chose to go with it, not withstanding some of the issues you raised.

As they say, you get what you pay for.


Andrew.
 

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Quote:
Originally posted by Colmino


One question in response to this. The resolution for the various JVC projectors is 1365x768. This seems odd to me. Granted, it's a close approximation of 4:3, but ultimately the fact is it's impossible to have mathematically "solid" scaling from 640x480, 1024x768 etc to a horizontal resolution with an odd number like 1365.


It's important to realize that I'm not for example overlooking the probability that a high resolution like 1365x1024 would begin to make the accuracy of one or two pixels moot. The point can best be explained by example. If you take a 640x480 image and scale it to 1280x960, the transition is easy: you just double each pixel horizontally and vertically (and throw in a filter).
Colmino,


You could "pixel double" the way you propose as a way of scaling - but that will give you a relatively inferior

picture. If you simply pixel double - you really aren't increasing the "apparent resolution" at all.


The mathematical transforms used in scaling are more sophisticated than what you propose above. Because of this

there really isn't much of an advantage to having the final resolution an integral multiple of the initial resolution.


Dr. Gregory Greenman

Physicist
 

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Quote:
Originally posted by David Panko



Your bulb cost estimate seems high. The 150CL has a lamp power control option which extends the bulb life to 2000 hours and the bulbs can be re-lamped by Atlas Lighting for around $500. Try searching the forum for "Cermax".

Dave,


Colimino would have to have his projector on for 27 hours a day in order to incur that kind of cost.


Colmino,


You do realize that the 1000 hour life of the Xenon bulb is 1000 hours with the projector ON. [ They don't "go bad"

just sitting there like fresh fruit or milk.]


Dr. Gregory Greenman

Physicist
 

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Discussion Starter · #18 ·
> Your bulb cost estimate seems high. The 150CL has a lamp power control option which extends the bulb life to 2000 hours and the bulbs can be re-lamped by Atlas Lighting for around $500. Try searching the forum for "Cermax".


This sounds quite a bit better. Naturally there must be some drawback(s) for utilizing this option. Reduced brightness seems like an obvious one. The 150CL, though a $18000 projector WITH a Xenon arc lamp, already only does 1000 ANSI lumens, which would barely be sufficient for what I intend with my living room, and then really only in the afternoon when the sun is shining more favorably. What sort of sacrifice would one be looking at by using the lamp power control option? And would there be drawbacks besides loss of brightness?
 

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Discussion Starter · #19 ·
> I was about to contribute to the thread along the lines of some the other contributors, but I quickly saw that the thread was going nowhere.

> No flaming intended, but Colmino, it seems to me that you should probably go with a RPTV or FP CRT.

> A well calibrated DiLA is probably the pinnacle of digital front projectors. A lot of forum members chose to go with it, not withstanding some of the issues you raised.


I fully acknowledge that in my quest for an "ideal" projector I am taking it for granted that there's going to at least be a close approximation, and that high-end equipment traditionally has one or two things wrong with it that the buyers "live with" (or pretend to ignore). By apparently demanding perfection, I may seem to be stepping on that tradition, and this will probably irritate some people. But I'm not all that concerned, as this forum has proven to be almost totally free of the immaturity that engenders asinine, unhelpful replies.


The introduction of DLP and D-ILA projectors seems to be taking traditionalists by surprise. It's as though paying big bucks for a product with almost no compromises is an unfamiliar experience. I just happen to have been of the mindset that that's the way it should have been in the first place, which is why I avoided projectors utterly, until recently.


Projector technology is very close to being something I'd pay for. It may even be there (depends on further details about the 5500, Vivid Red and 150CL).


>> If you take a 640x480 image and scale it to 1280x960, the transition is easy: you just double each pixel horizontally and vertically (and throw in a filter).

> You could "pixel double" the way you propose as a way of scaling - but that will give you a relatively inferior picture. If you simply pixel double - you really aren't increasing the "apparent resolution" at all.


Hence the reason I added the bit about a filter. Ie, the same no-brainer process you get when you resize Windows Media Player (as opposed to unfiltered scaling, Playstation1-style). And when I say "filter," I simply mean any algorithm you want to use.


> The mathematical transforms used in scaling are more sophisticated than what you propose above. Because of this there really isn't much of an advantage to having the final resolution an integral multiple of the initial resolution.


This is arguable. For example, take a 16x16 image, blow it up to 32x32, toss in your filter of choice. The transformation is straightforward. But now try 17x17 to 32x32. Not so easy, and frankly the compromises involved will make the image considerably less recognizable. Expand this scenario to cover instances such as scaling to 1365x1024. The effect is minimized, but it is still there.


This is getting a little off-topic and at this stage in my research it's really a non-issue (let's just say that I'm willing to compromise in much the same manner that prosumers accept much larger compromises).
 

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I'd say you need to be honest with yourself as to what you really want.


If you want the closest to perfection get a 9" CRT like a G90 or Vision 1.


The latest digital projectors are not even close to perfection. Don't kid yourself that they are. They are relatively cheap for the performance that they do offer though and are smaller and much less fussy to set up. But close to perfect they are not.


My Marantz 12S1 could be brighter, have more resolution and contrast, better black levels and on and on. What it does represent to me is the first reasonably priced projector that I wanted to own. The JVC D-ILAs have the potential to be better but require calibration, a hush box and an external scaler to do it. I have seen the $98k Runco 3 chip DLP and even that can be improved. Although with 3,000 lumens its about as good as a digital pj gets today.


Don't forget to talk your wishes over with Jason at AVS. He can give you a pretty good idea of current street prices depending on what you really want to accomplish.
 
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