Anyone moving on from CRT in 2017? Anyone still interested in the hobby? - Page 2 - AVS Forum | Home Theater Discussions And Reviews
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post #31 of 75 Old 04-07-2017, 04:22 PM
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I am stockpiling projectors, and retubing every one that comes in the door if it shows any visible tube wear,
simply because I have piles of tubes. I can afford to keep and store them, and I have the idea in mind to build
a cockpit based flight simulator using multiple projectors which will require me to decide to commit some money toward that and a place to set it up because to do it right it'll need a 12 foot ceiling or more and about 500 square feet of floor space. With good air conditioning, because nine Marquees generate a fair amount of heat.

I have enough experience with some real cockpit simulators used by certain branches of the US Armed Services that I can pretty much draw out all the visual systems component by component from memory. I could build simplified versions for a reasonable price. It's actually building the cockpit that becomes somewhat more involved and expensive.

CRT for me is, was, and shall remain a hobby, and who cares if my version of it is to have far more units than I can actually use at once?

It's my fun. One of my many hobbies.

That digital projectors have (for the better units) caught up, depending on your criteria for comparison, matters not to me. The fact remains that I can get a Marquee Ultra or G90 or 909 for considerably less than the cost of a new digital that can match it, so in this case the economy of CRT still makes it a viable choice if you are willing to accept the size, weight, and maintenance requirements of the CRT projector.

Collecting so many CRT projectors may also be a mental illness. I concede that possibility.
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post #32 of 75 Old 04-08-2017, 05:52 AM
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Quote:
Originally Posted by cmjohnson View Post
That digital projectors have (for the better units) caught up, depending on your criteria for comparison, matters not to me. The fact remains that I can get a Marquee Ultra or G90 or 909 for considerably less than the cost of a new digital that can match it, so in this case the economy of CRT still makes it a viable choice if you are willing to accept the size, weight, and maintenance requirements of the CRT projector.
.

To be fair, one should equalize the cost between projectors both new and used.

Current projector - JVC RS25 and Marantz VP15S1
Future projector - pre-ordered new JVC from AVScience
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post #33 of 75 Old 04-08-2017, 06:09 AM
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A valid point. The last CRT projector built was made by VDC in either 2012 or 2013.
I can't presume that everybody is aware that CRT projectors haven't been made in about five years and more.

Occasionally you may run across a new old stock projector, though. That still doesn't make it new. Some electronic components
begin to age as soon as they're made whether the unit they're in is powered up and running or sitting in the box on a shelf.
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post #34 of 75 Old 04-08-2017, 07:33 AM
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I've seen the latest model digital projectors and I have an RS45 hung below my modded Marquee Ultra. While I think digitals project a fine picture today with really nothing to complain about, I still find that a well tuned, top notch CRT projector creates an image that is more "real" to me, and it draws me into the movie more. It's not something that can be easily defined by measuring resolution, MTF, or contrast ratios. In fact, those measurements can make me wonder why I prefer the CRT image.

But then again, some people prefer the slightly less accurate technical performance of vacuum tube audio equipment. It sounds better to them.

I guess I can say that CRT just looks better to me. Tube video is more satisfying to me than digital video. The comparison to tube vs. solid state audio is, in my opinion, quite valid and relevant.
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post #35 of 75 Old 04-08-2017, 07:49 AM
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All I am trying to say is, that is is ok to have and share your OPINION on the merits of digital and CRT, but to state one or the other as factually "better" drives me to comment. I have seen the exact same thing when it was tubes VS transistors and vinyl VS CD.

IMHO such definite statements does not make much sense and are at best useless.

What is a home theater without good sound??
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post #36 of 75 Old 04-08-2017, 08:01 AM
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Quote:
Originally Posted by cmjohnson View Post
I've seen the latest model digital projectors and I have an RS45 hung below my modded Marquee Ultra. While I think digitals project a fine picture today with really nothing to complain about, I still find that a well tuned, top notch CRT projector creates an image that is more "real" to me, and it draws me into the movie more. It's not something that can be easily defined by measuring resolution, MTF, or contrast ratios. In fact, those measurements can make me wonder why I prefer the CRT image.

But then again, some people prefer the slightly less accurate technical performance of vacuum tube audio equipment. It sounds better to them.

I guess I can say that CRT just looks better to me. Tube video is more satisfying to me than digital video. The comparison to tube vs. solid state audio is, in my opinion, quite valid and relevant.
I agree here, but please don´t fall into the "less accurate technical performance" pit..That is only what your instruments tells you The things we can measure is far from what the ear/brain eye/brain system is capable of.
Remember when the Japanese made amplifiers with 0,0000001 % distortion and the sounded awful (still does) just because we did not know how to measure other parameters (DIM TIM aso aso) . Still today there is no way to measure how an amplifier sounds or a loudspeaker or how a projector looks like. Measurements are only a helping tool to try to make things better, but the ultimate test is always human's hearing or looking.

What is a home theater without good sound??
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post #37 of 75 Old 04-08-2017, 08:07 PM
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Well, I do not allow tech specs tell me what to buy, but I do use them as an indicator of the level of engineering that went into a product.

I believe that ultimately you need to find the performance of the item in question pleasing to you. This is often accompanied by
generally respectable specifications.

It would not surprise anyone to find out that the best rated solid state amplifiers, for example, all measure fairly close to each other in several important parameters.

Specs are a valid indicator. But not the ONLY valid indicator.
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post #38 of 75 Old 04-16-2017, 01:02 PM
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Is ok to have and share a OPINION on the merits of CRT and Digitals today. But also very clear what really the agenda is. When they have the garage full of CRTs. And clams CRT still is better than any digitals. This will just mislead people with less knowledge about different technologies.

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post #39 of 75 Old 04-16-2017, 01:20 PM
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I had my CRT projector for almost 15 years. Last year the picture went bad. I wasn't motivated to try to fix it. I decided the time was right to jump to digital. The one thing I miss is the ability of the CRT to go to TOTAL black in a dark scene. In every other respect, my JVC is better-- equal or better CR, sharper, brighter, far easier to set up and calibrate, so much so that I didn't have to pay anybody to do those things. I even bought a colorimeter and got the autocalibration software, meaning I can always tweak it myself.
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post #40 of 75 Old 04-16-2017, 05:49 PM
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What CRT projector did you have?

I myself stack a JVC RS-45 under my Marquee Ultra. I alternate between the two and by the experience gained from this, I have evolved some definite preferences.

If the movie is computer generated animation, I ALWAYS like the look better on CRT. That movie seen on the RS45 just has a look to it that is so artificial it throws me far from that point where you achieve suspension of disbelief, which is, at least for me, where you have to be in order to really enjoy a movie. The same movie seen on CRT is simply more pleasurable for me to watch. It's hard to explain why it feels so different but that's how it is for me. Honestly it's hard even for me to pin it down.

When watching live action movies, I don't get that same feeling of the images being so different. Oh, the differences are there, but they are felt (by me) to be far more minor, even trivial.

I can say that I don't find the black levels to be at all equal. While on paper the RS45 has a higher contrast ratio than the Marquee, in the real world (my theater room), my CRT projector doesn't illuminate the screen with no image playing. The RS45 does, I can see the screen faintly in the otherwise extremely dark room. And I'm NOT seeing any black level advantage going to the RS45. I've done comparisons and neither one really manages to edge out the other. I'd call it a tie in actual movie watching conditions.

Either machine is capable of delivering more brightness than I even like. If the bright scenes can make me squint, and both projectors can achieve this, why would I want or need more brightness? I don't.

I have no desire to remove either projector from my setup. I see no reason to throw out the old technology when it still works well and I don't seem to be lacking for spare parts for it.
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post #41 of 75 Old 04-16-2017, 06:26 PM
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It's an NEC XG135LC. It's now sitting in the back room. I mentioned the ability of the CRT projector to go totally black, which I miss, but only rarely. I disagree with you about CRT somehow "feeling" better. Honestly, that sounds like a vinylphile extolling the virtues of vinyl over digital, even though digital is objectively better. I was watching Dr. Strangelove the other day, and was extremely pleased with the filmlike presentation (further enhanced by the ability of the JVC to do 24p). There was nothing lacking. The CRT simply can't match the digital sharpness.
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post #42 of 75 Old 04-16-2017, 06:40 PM
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I could, and will, argue that the ability to resolve the individual pixels as squares on the screen with slight gaps between them is not true image sharpness, but is instead a matter of the optical system having the resolution required to resolve the actual image of the LCD, DLP, or D-ILA imaging device. That by itself is not a guarantee of actual sharpness in the image as there is a lot of processing going on between the HDMI port and the imaging device itself, and it's not always perfect.

I've seen some really awful LCD projectors that looked horrible but you could count every pixel if you cared to.

The best CRT projectors really are very sharp indeed if properly aligned and set up. If they resolve all the image content and do it well, if edges are sharp and clean and there's nothing blurry there that isn't supposed to be there, if finely textured images like hair and cloth actually are presented with great detail, then that's really, really sharp no matter what the display technology is.

I do NOT consider my RS45 to be sharper than my Marquee. Oh, there's what I might call an "edginess" to its image quality that others may call sharpness, but what my eye tells my brain, and my brain agrees, is that I'm seeing a very subtle screen door effect which I find to be distracting and very much not a "real" look. But when it comes to resolving details in the picture? The Marquee appears to give up nothing in any real viewing sense.

That is my subjective interpretation of what I am seeing with my own eyes with my own equipment. Your experiences and opinions may be quite different and of course that's all right. I don't try to tell people what to think. I just tell them what I think myself.


I do want to note, though, that an 8" XG135, even an LC version, falls rather short of the visual quality standards delivered by a top 9" machine. With roughly 40 percent more tube surface area to work with, any good 9" machine is really in another league beyond that of any 8" machine.

So, while a digital may beat out your XG135 (and you didn't even specify if it's an LC model or an AC model), honestly I'm not surprised that would be the case, but a G90, 909, or modded Marquee 9500LC is a significantly better projector and just that more capable of holding its own against a digital challenger.

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post #43 of 75 Old 04-16-2017, 07:07 PM
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while a digital may beat out your XG135 (and you didn't even specify if it's an LC model or an AC model)
Actually, I did. Reread my post. And yes, 9 inch CRTS are quite sharp, but at the time they were too expensive for me. The other factor is that it's FAR easier to achieve ultimate sharpness with a digital. As for screen door, there simply isn't any on the JVC, especially with eshift.
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post #44 of 75 Old 04-16-2017, 08:05 PM
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Yes, there is some slight SDE visible on my RS45. Although not quite visible under ordinary viewing conditions at normal viewing distances, I have found that I'm sensitive enough to it that I sometimes see it when I'm scanning my eyes across the image at just the right speed in just the right kind of scenes. But it is also fair to note that I often see scan lines in CRT units (not generally at 1080p, though) if my eyes scan vertically at just the right speed, too. And I am phenomenally sensitive to the rainbow effect as found on single chip DLP and LCD projectors that use a spinning color wheel

Again, I do not believe that focusing pixel edges is the same thing as sharpness of detail in an image. While the recent crop of digital projectors (in the upper end of the market, to include all JVC D-ILA products) have no lack of sharpness, I still do not consider them to be actually any sharper than a top rated CRT projector in top condition in any real world sense. Again this is my opinion, not presented as objective fact.

At the end of the day, though, I can enjoy the image from anything mentioned so far in this topic. I simply am not in any hurry to replace any of my CRT projectors with any digital units. Not even if I had a sufficient income that I could easily afford to do so.
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post #45 of 75 Old 04-17-2017, 12:24 AM
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Anyone moving on from CRT in 2017? Anyone still interested in the hobby?

This is the topic,


I don't understand why hard CRT enthusiasts like some here, have to do everything they can to discredit the current technology.
To believe that they will sell more of the reason, It is so transparent that its funny. And on all forums together also. The few who still holding on with CRT will do so to its not possible to get parts.
CRT is a cool hobby and if I get a great 9" latest model for the right price I might have fun with it. But to pay 1000 dollar I believe is total madness today. When you can get a budget 1080P projector for around the same that will be better on almost everything then if you consider a normal persons choice.

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post #46 of 75 Old 04-17-2017, 10:18 AM
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Originally Posted by cmjohnson View Post
Yes, there is some slight SDE visible on my RS45. Although not quite visible under ordinary viewing conditions at normal viewing distances, I have found that I'm sensitive enough to it that I sometimes see it when I'm scanning my eyes across the image at just the right speed in just the right kind of scenes.
I think I see the problem. You have a much older JVC projector. Your RS45 only has 50000:1 CR. My RS500 has 120000:1. Your projector is limited to 1080p. My projector has 4K eshift. You need to look at the latest technology.
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post #47 of 75 Old 04-17-2017, 05:32 PM
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I bought the JVC from a very good friend of mine who recently upgraded to an RS500.

I've watched many movies in his home theater (a very nice one!) on this very projector as well as on his newer one,
and to be quite honest on HD material (1080p) I'm not certain that I actually saw any difference. Oh, with quasi-4K material,
yeah, you can see a difference, but at the same resolution I can not be sure that the image was different enough for me to notice.

I'm not in a position to spend the money on an RS500 at this time, and frankly not very interested in doing so in any event. The
fact is that my screen size in my existing home theater room is about as big as it can realistically get, at 8 feet wide, as the room
is not large. To go into 4K territory I would want a substantially larger image to make the best of it. So for reasons of cost
and installation limitations I'm just not in the market for an RS500.

Now, if I had NO CRT projector, at this point I would most likely not be looking for one. I'd go for something at least equal to
the RS45 and would seriously look at an RS500 or something similar.

But I have no motivation at all to abandon a perfectly healthy projector that has fresh tubes in it, in order to gain image quality
differences that I'm not even sure I place much value on.

The fact of the matter is, the longer I wait to upgrade, the better the upgrade will likely be at any given price point.
I will not go for an incremental improvement at substantial cost. I would demand a substantial improvement if I am to spend a
substantial amount of money. And, frankly, if you consider the RS45 or even the RS500 to be an improvement, my own experience
is that the improvement is incremental rather than substantial.

The jump from 800x600 resolution to 1080p was big enough to call it substantial. I'd need pretty much the same relative
picture improvement before I'd seriously think about spending thousands of dollars to upgrade beyond 1080p.
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post #48 of 75 Old 04-17-2017, 05:58 PM
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Originally Posted by cmjohnson View Post
if I had NO CRT projector, at this point I would most likely not be looking for one. I'd go for something at least equal to
the RS45 and would seriously look at an RS500 or something similar.
That was precisely the situation I was in 14 months ago. My projector died, and the realities of the projector market told me it was time to move to digital. I did so, and I'm never looking back. What I quoted tells me you also recognize that reality.

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post #49 of 75 Old 04-17-2017, 07:47 PM
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Oh, I do recognize that reality, but I have absolutely no desire to move toward it to any greater extent than I already have,
and I can assure you that I am very, very far indeed from being done with CRT projectors. I'm sure that my reasons for this
weigh something around 3200 pounts in total. Yes, I have a lot of units, and my plans for them are uncertain but I am giving
very serious consideration to a flight simulator project that will use up almost all of them. Which may be impractical even to the point
of absurdity but I can certainly think about it as much as I want.

It may be a character weakness, but I just can't pass up a 9" CRT projector if I can buy it for a little bit of almost nothing. Need for it
has absolutely nothing to do with it. I guess I just don't mind collecting dinosaurs.

My latest acquisition was once owned by Sylvester Stallone if I was told the truth. Which does not make it more valuable, but at least
there is a story to go with it.
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post #50 of 75 Old 04-23-2017, 12:14 AM
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Comparing the sharpness of a crt to a Jvc/lcos is an apt comparison, suggesting this level of sharpness represents all digitals is not.
A Dlp can't do anything close to the static contrast that a crt or Jvc can do in a dark scene, even if an iris is used well to modulate the light output.
What a Dlp has that the other projection technologies lack is the ability to place bright pixels directly next to dark pixels in a checkerboard pattern (ansi contrast) more effectively. This is what creates the sharp contrast in fine details of the image. This is why a Dlp is the best device for creating bright and sharp high contrast scenes, while both crt and lcos lag behind. It doesn't matter how high the resolution is if the contrast isn't there to clearly define the pixels and detail.

Dlp also has the advantage of a high fill rate, mitigating the screen door effect at any reasonable seating distance.
Interestingly Oled is quite capable of high ansi contrast, high static contrast, and high dynamic contrast. This is why a crt or lcos can never compare for contrast. Oled effectively combines the best aspects of crt with the best aspects of dlp. Screen door is still an issue with Oled, although 4k seems to mitigate it for the most part.
This could be achieved with dlp as well via the use of multiple dmds in sequence. Dmds are incredibly efficient at reflecting light in comparison to an lcd pixel's capability to transmit light. Placing multiple dmd's in sequence provides an immense increase of static contrast.

Of course this is all theoretical, and aligning multiple dmds sequentially may be an incredible engineering task while keeping them aligned in a consumer device might be near impossible. No point in such an immense increase in contrast if it would negatively impact the fine details a dlp is capable of resolving.

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post #51 of 75 Old 04-23-2017, 07:04 AM
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DMD alignment in a 3 chip projector is achieved by aligning all three chips on their respective faces of the optical core prism to which they are attached. The standard for aligning those three chips to perfect convergence is less than half a width across the entire surface of the DMD.
That's the standard Texas Instruments set back around 1999. I believe it still holds true today even though we're now talking about 4K DMDs, rather than 800x600 DMDs. So the tolerance is getting very, very fine indeed.

But it's routinely achieved on every commercial 3 chip DLP machine that ships out the factory door. Really not a big deal.
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post #52 of 75 Old 04-24-2017, 12:11 PM
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DMD alignment in a 3 chip projector is achieved by aligning all three chips on their respective faces of the optical core prism to which they are attached. The standard for aligning those three chips to perfect convergence is less than half a width across the entire surface of the DMD.
That's the standard Texas Instruments set back around 1999. I believe it still holds true today even though we're now talking about 4K DMDs, rather than 800x600 DMDs. So the tolerance is getting very, very fine indeed.

But it's routinely achieved on every commercial 3 chip DLP machine that ships out the factory door. Really not a big deal.
True enough, but not really relevant to the theoretical sequentially aligned dmd layout I am referring to. The key word there is "sequential", as in one after the other. Placing 2 dmds, one after the other in the light path would essentially multiply the contrast of one chip by the other, providing class leading contrast ratios.
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post #53 of 75 Old 04-24-2017, 04:33 PM
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What you would propose would require an additional imaging optical pathway between the two DMDs and the image geometry requirements would be quite stringent. You'd have to have absolute flatness of field and your total tolerance for keystone, pincushion, linearity, or any geometric parameter would still have to be under 1/2 a pixel width over the total area of the DMDs. That would require multi element optics which will inevitably have some transmission losses, and they will add a certain amount of veiling glare which would probably reduce the available contrast ratio more than might be gained with stacked DMDs via this optical pathway.

And then you have another problem: What happens to your light output if DMD 1 is outputting 10 IRE (10 percent of max brightness) and DMD 2 is also set to 10 IRE? It's division. The net system output is 1 IRE.

Follow the math for just a few points.

DMD 1, 100 IRE, DMD 2, 100 IRE: Output is 100 IRE minus path losses.
DMD 1, 50 IRE, DMD 2, 50 IRE, output is 25 IRE minus path losses.
DMD 1, 20 IRE, DMD 2, 20 IRE, output is 4 IRE.
DMD 1, 10 IRE, DMD 2, 10 IRE, output is 1 IRE.
DMD 1, 1 IRE, DMD 2, 1 IRE, output is .01 IRE.

You have created a decidedly non-linear contrast modulator. In fact it appears to work on a square root law.

I don't think that would be at all useful unless you wanted to crush blacks like nobody has ever crushed them in all of history.

If you were to program DMD 2 to operate on a different contrast mapping principle, things would get quite interesting indeed,
but I'm in no way confident that stacking two DMDs by any practical means will simply provide the benefit of a deeper darker black level without other negative consequences.
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post #54 of 75 Old 04-24-2017, 04:47 PM
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Originally Posted by cmjohnson View Post
What you would propose would require an additional imaging optical pathway between the two DMDs and the image geometry requirements would be quite stringent. You'd have to have absolute flatness of field and your total tolerance for keystone, pincushion, linearity, or any geometric parameter would still have to be under 1/2 a pixel width over the total area of the DMDs. That would require multi element optics which will inevitably have some transmission losses, and they will add a certain amount of veiling glare which would probably reduce the available contrast ratio more than might be gained with stacked DMDs via this optical pathway.

And then you have another problem: What happens to your light output if DMD 1 is outputting 10 IRE (10 percent of max brightness) and DMD 2 is also set to 10 IRE? It's division. The net system output is 1 IRE.

Follow the math for just a few points.

DMD 1, 100 IRE, DMD 2, 100 IRE: Output is 100 IRE minus path losses.
DMD 1, 50 IRE, DMD 2, 50 IRE, output is 25 IRE minus path losses.
DMD 1, 20 IRE, DMD 2, 20 IRE, output is 4 IRE.
DMD 1, 10 IRE, DMD 2, 10 IRE, output is 1 IRE.
DMD 1, 1 IRE, DMD 2, 1 IRE, output is .01 IRE.

You have created a decidedly non-linear contrast modulator. In fact it appears to work on a square root law.

I don't think that would be at all useful unless you wanted to crush blacks like nobody has ever crushed them in all of history.

If you were to program DMD 2 to operate on a different contrast mapping principle, things would get quite interesting indeed,
but I'm in no way confident that stacking two DMDs by any practical means will simply provide the benefit of a deeper darker black level without other negative consequences.
Like I said, I don't know if it's possible/practical.
As you have figured out, you certainly couldn't just throw the chips into a machine with typical image processing software. The image processing would need to be designed from the ground up. Then there is the issue of alignment, but if they can manage it with 3 chip dlps, it may very well be possible with 2 in sequence. The bit about contrast loss due to optics is interesting, funny how theoreticals break down when figuring out practical application. While the static contrast would be multiplied by a factor of 1000-1500, ansi/fine detail contrast would probably take a hit.
I would never say it's viable/practical, but in theory it would be one hell of a high contrast performer.

I guess the main point I was trying to make here is Lcos does not represent all digitals. It is the closest in performance characteristics to crt but that is also it's primary failing. Crt's and Lcos are great for a lot of things but pronounced fine details in brighter scenes is definitely not one of them. A lack of contrast in fine details leads to a direct loss of perceived detail/resolution.
Sure when you get right up close to the screen with measuring equipment and a test pattern you can find 1080 lines on a crt, but things get a little murky when you are watching actual content at seating distance.

Last edited by AVMB; 04-24-2017 at 04:52 PM.
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post #55 of 75 Old 04-24-2017, 06:18 PM
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Nobody is going to state that CRT near its resolution limit is going to resolve details at the kind of high MTF values that are possible with DLP and some other technologies. Not even me. CRT as a technology has reached its end stage and I think it has acquitted itself extremely well, given that its root technology, the vacuum tube/thermionic valve is only three years too young to be a Victorian era invention.

A skilled person can make a basic CRT in his own garage workshop if he has the knowledge and tools that are not at all difficult to come by, and yet, CRT has held out for this long against digital panel technologies that require large factories with capital equipment investments that are always well into the millions of dollars.

I find that to be remarkable. It speaks volumes about the basic robustness of the principles embodied in the cathode ray tube.

LCOS is basically a reflectively backlit LCD but the backlight is actually front illumination, shining thru the LCD, off a mirrored back reflectors, and then on to the optical system. It should have more or less the same contrast ratios and MTF values of straight transmission
type LCD panels of similar manufacturing technology.
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post #56 of 75 Old 04-24-2017, 08:28 PM
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Quote:
Originally Posted by cmjohnson View Post
Nobody is going to state that CRT near its resolution limit is going to resolve details at the kind of high MTF values that are possible with DLP and some other technologies. Not even me. CRT as a technology has reached its end stage and I think it has acquitted itself extremely well, given that its root technology, the vacuum tube/thermionic valve is only three years too young to be a Victorian era invention.

A skilled person can make a basic CRT in his own garage workshop if he has the knowledge and tools that are not at all difficult to come by, and yet, CRT has held out for this long against digital panel technologies that require large factories with capital equipment investments that are always well into the millions of dollars.

I find that to be remarkable. It speaks volumes about the basic robustness of the principles embodied in the cathode ray tube.

LCOS is basically a reflectively backlit LCD but the backlight is actually front illumination, shining thru the LCD, off a mirrored back reflectors, and then on to the optical system. It should have more or less the same contrast ratios and MTF values of straight transmission
type LCD panels of similar manufacturing technology.
Fair enough. I'm not sure how lcd's stack up, I do know that the Jvc's are often berated for sub par ansi contrast compared to dlp, but I don't hear much about Epsons in that regard. I asked this question awhile back when I was looking into switching out an Optoma Dlp for an Epson 5025ub, but no one seemed to know anything about the ansi contrast of Epsons, and I couldn't find anything myself.
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post #57 of 75 Old 04-24-2017, 09:32 PM
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I can tell you that I own a JVC RS45 D-ILA projector and was watching it tonight, alternating between it and my somewhat modded Marquee Ultra. It was really a rather close contest. Not being concerned about test patterns, I simply watched a movie and switched between projectors.

I did not find the contrast of the RS45 to be lacking, although it failed (by a slim margin) to match the utter depth of blacks possible with the Marquee. It did well enough that I would not likely have really noticed its falling short of true black if I were not actively comparing it to a CRT projector that actually manages that "Who turned out the lights" true black. And yet still resolves (barely) above black details quite well thanks to well adjusted gamma on the HDMI input card plus gamma tweaks on the video input board.

I will not contest that I found the RS45's image to be somewhat sharper. Not by a wide margin, mind you, but it was noticeable.

However, I still find the CRT image quality to be smoother without lacking for detail, and it just feels more real to me than the image from a digital projector. It's hard to explain why that is.

The RS45 is a model that is now several years old. It's yesterday's news and I have every reason to believe that its successors are even better.
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post #58 of 75 Old 04-26-2017, 08:35 PM
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Originally Posted by cmjohnson View Post
I can tell you that I own a JVC RS45 D-ILA projector and was watching it tonight, alternating between it and my somewhat modded Marquee Ultra. It was really a rather close contest. Not being concerned about test patterns, I simply watched a movie and switched between projectors.

I did not find the contrast of the RS45 to be lacking, although it failed (by a slim margin) to match the utter depth of blacks possible with the Marquee. It did well enough that I would not likely have really noticed its falling short of true black if I were not actively comparing it to a CRT projector that actually manages that "Who turned out the lights" true black. And yet still resolves (barely) above black details quite well thanks to well adjusted gamma on the HDMI input card plus gamma tweaks on the video input board.

I will not contest that I found the RS45's image to be somewhat sharper. Not by a wide margin, mind you, but it was noticeable.

However, I still find the CRT image quality to be smoother without lacking for detail, and it just feels more real to me than the image from a digital projector. It's hard to explain why that is.

The RS45 is a model that is now several years old. It's yesterday's news and I have every reason to believe that its successors are even better.
Hmm...something you said in an earlier post has me scratching my head. You said "lcos is basically lcd with a reflective backplane, it should have the same contrast as lcds". We know this isn't true though, we know that whatever tech Jvc has embedded in their
Lcos (Dila) projectors provides immense static contrast performance compared to both Sony's implementation of Lcos (Sxrd), and Epsons implementation of Lcd.

With that in mind, I might be incorrect in saying that Lcos offers sub par ansi contrast performance. It might be the case that the sub par ansi contrast performance (offset by immense static contrast), is specific to Jvc's implementation of Lcos. For all I know Sony Lcos and Epson Lcd might be quite good for ansi contrast (though both lag far behind Jvc for static contrast), but I'll be damned if I can actually find any info on it for either of them. I'd really like to figure that out, because I want better static contrast but I don't want to give up the excellent fine detail contrast/sharpness of the Optoma Hd25. I also don't want to downgrade in motion performance for 60 frames per second gaming, but that's a topic for another thread.
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post #59 of 75 Old 04-29-2017, 05:56 PM
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Upon further fine tweaking of my own Marquee this evening, comparing its sharpness directly to that of my RS45 while watching Rogue One, alternating between projectors, I was able to sharpen up the astig and focus on the Marquee enough that there really is no difference in sharpness between the two. By doing so, other visible differences in image quality seem to have become reduced.

There were times when I could not actually tell which projector I was watching from the image on the screen. I had to look up and see which one was projecting.
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post #60 of 75 Old 05-17-2017, 06:09 PM
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And now I got to spend some time really working with one of my G90s, in this case, the one that used to belong to Sylvester Stallone, since it's my newest one and it needed a thorough checkout. I replaced the lightly worn green tube in it.

A stock G90 is quite the performer right out of the box, so to speak. Once I had the settings configured correctly, I aligned and converged it on the screen and then stuck in a few blu-rays and just played through a few of them.

I admit this: A stock G90 is obviously sharper than a stock Marquee and where the G90 is really a superior performer is in keeping the image sharp at high contrast levels.

I just need to get around to finishing out a project which, if successful, should make the Marquee match the G90 in terms of focus performance.

The G90's sharpness really challenges the RS45. It's hard to really say one is sharper than the other, Of course there is a resolved fixed pixel structure with the RS45 but as I said some posts ago, being able to resolve pixel edges is not the same as resolve-the-detail sharpness.

It is possible to have a digital projector whose real sharpness performance falls short of the maximum possible sharpness as limited by the structure of the imaging panels.

The G90's image takes on a "3D look" that I have so far seen strongly only on the RS45 and not so much on the Marquee.

But then again, there's a punch to the image coming out of the Marquee that is rather special. The Marquee video amplifier chain is short, direct, and very dynamic.

I'd like to see Marquee video amplification systems in a G90 chassis. Or bring G90 sharpness into the Marquee. (Which may be possible and actually not difficult.)
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