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Discussion Starter · #1 ·
I frankly don't have much use for dynamic irises. All they do is screw up the gamma and lower the light output only on very dark scenes, leaving the vast majority of program material unaffected.


On the other hand, high native contrast provides excellent dark scene performance as well, while providing all of the advantages of high contrast for all of the program material.


A fixed iris can greatly improve native contrast at the expense of light output. If you have enough light to spare, this is a worthwhile trade-off. The problem is that most fixed irises just don't work very well--they are very effective at lowering light output while having little or no effect on contrast.


In contrast (no pun intended), Sharp's dual iris system works fabulously well. It actually raises contrast MORE than it reduces light output. Consider these numbers for the Sharp 20K on a 100" StudioTek.

Iris Open

Peak output: 27.5 fL

Black: 0.016 fL

Contrast: 1685

Iris Medium

Peak output: 16.4 fL

Black: 0.004 fL

Contrast: 4014


No other manufacturer has offered anything that even comes close to this performance. The Medium iris setting lowers light output 40%, but it increases contrast 138%. The High Contrast setting increases contrast even more, but the hit on light output brings it below the SMPTE-recommended 14 fL target peak output on my screen.


For those who prefer the DLP look, this iris system could do wonders for their contrast performance. I am thinking of projectors like the Samsung, Runco (formerly Planar), and Vivetek (and others) LED units that have native contrast near 3000:1. With a Sharp iris, they would provide approximately 7000:1 with adequate light output.


This seems like a no-brainer to me. Since Sharp seems to be pretty much out of the high-end projector business, I wouldn't think they would have any objections to licensing this technology.
 

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Quote:
Originally Posted by TomHuffman /forum/post/18290591


This seems like a no-brainer to me. Since Sharp seems to be pretty much out of the high-end projector business, I wouldn't think they would have any objections to licensing this technology.

I'm with you, but I doubt anybody would need to license it. I don't think it is unique enough. I don't have the numbers, but Marantz has a dual manual iris in the 11S2.


I have been working on some of the manufacturers for years to put dual irises in DLPs. I believe I made my feelings pretty clear to Marantz before they came out with a projector with that.


One of the problems at times is getting people to even understand that on/off CR matters. It doesn't do a lot of good for me to suggest a method to improve on/off CR if the people working for the company don't understand its role in images (especially if they claim it is bogus and makes no difference). So, if I think they don't understand the role of on/off CR I work that angle first. Then if they seem to come around at all I may suggest a method of improving on/off CR, like the dual iris thing with DLPs. I have talked to somebody from one of the companies you mentioned about this and hope that they will consider it for their next projector. I think their current projector would have been better (and would have competed better for them) if they had done it in that model.


One of my biggest frustrations right now is that we seem to have moved backwards with these LED DLPs in a certain sense. I realize the manufacturers want more light output, but I think a dual iris system like Sharp and Marantz had would be a great choice. They could offer more light output for those who value it most, while offering higher native on/off CR for those who value it most and can live with the lower light output. And the nice thing with LEDs is that you can close the manual irises down and still do the dynamic stuff since you have the LEDs for that part now. As it is I think most of these companies doing LED DLPs are letting native on/off CR suffer for more light output, but they might be able to offer even higher light output at lower CR for some people and/or situations. With only 1 fixed iris you kind of have to pick a tradeoff between lumens and on/off CR instead of letting the user do it from more than one choice. Therefore you might not be able to go as high for lumens or as high for on/off CR (although the dual iris method doesn't provide both at the same time). When I had the Sharps I know I valued having the open iris option even though I probably only used it 10% of the time.


I've thought about buying one of the LED DLP units and putting 2 irises in, but then they wouldn't be manual and I wouldn't be able to pick the higher light output mode like when the projector has a button on the remote for quickly switching. It would be more like an hour or more for me to take the irises out and so I wouldn't be likely to go back and forth. But the LED DLPs are also expensive enough that I probably don't want to go messing with one. So, I talk to the manufacturers or people who might have contact with manufacturers and try to get them to put dual manual irises in their DLP projectors.


BTW: The "Future Improvements" of my article about CR almost 4 years ago here:

http://www.hometheaterhifi.com/volum...06-part-5.html


was largely there as backup for me trying to talk certain manufacturers into doing things to improve their on/off CRs (including dynamic irises and dual irises with their DLPs).


So, as far as your question of why more don't do it, maybe you can blame me for not being more successful at getting some of them to do it.



Also, I won't bring up the advantages of dynamic irises here, but they do have them over dual irises too. But as I mentioned, with LEDs the manufacturers don't have to choose. They can give the users the options for manual irises and the options for the dynamic system. Just give the users the choices to use any combination and I think more users would be happy.


--Darin
 

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Discussion Starter · #3 ·

Quote:
Originally Posted by darinp2 /forum/post/18290694


I'm with you, but I doubt anybody would need to license it. I don't think it is unique enough. I don't have the numbers, but Marantz has a dual manual iris in the 11S2.


I have been working on some of the manufacturers for years to put dual irises in DLPs. I believe I made my feelings pretty clear to Marantz before they came out with a projector with that.


One of the problems at times is getting people to even understand that on/off CR matters. It doesn't do a lot of good for me to suggest a method to improve on/off CR if the people working for the company don't understand its role in images (especially if they claim it is bogus and makes no difference).

If that's the case, then the marketing department and the engineers are clearly not talking to one another since these displays are so often marketed with prominent (and often grossly exaggerated) claims about contrast performance.


Marantz did license some Sharp technology, so perhaps they had the same iris system. Greg Rogers' numbers for the two projectors were similar, except, interestingly, the Marantz did considerably better with the iris fully open.

Marantz S2

Iris 3

Peak output: 36.9

Black: 0.011

Contrast: 3340


Iris 2

Peak output: 18.7

Black: 0.003

Contrast: 5350


Iris 1

Peak output: 16

Black: 0.002

Contrast: 8190:1

Sharp 20K

High Brightness

Peak output: 42.9

Black: 0.02

Contrast: 1900


Medium

Peak output: 20.7

Black: 0.005

Contrast: 4510


High Contrast

Peak output: 18.4

Black: 0.003

Contrast: 7260


All numbers are from a 100" StudioTek. His Sharp performed a little better than mine.


Put one of these dual irises in one of the LED units to give it a native CR of 4-5000:1 and I would get very interested.
 

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Darin. A quick question. In a dual iris system, where are the irises placed? For example, one after the lamp but before the ? and ane between the ? and the ? or in the lens?
 

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I think it would be even greater if they could get the dual iris technology to work dynamically. If so, on bright scenes, both Irises would be fully open, the native CR performance would be worse at that point but the scene would be dominated by ANSI CR anyway. As the APL dropped, the dual irises would start to close until at the bottom, you would have them at their minimum apertures. The sharp 20k in that case acheives an 8k:1 on/off and on/off would dominate ANSI at those APL levels. Your total contrast ratio for the projector would be fairly high as well.


The benefits would be a much higher dynamic contrast ratio than the projector was capable of in any iris position originally and a much higher usable contrast ratio for low APL scenes when compared to a projector with a dynamic iris that only changes the light level.
 

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Discussion Starter · #6 ·

Quote:
Originally Posted by mrlittlejeans /forum/post/18293168


I think it would be even greater if they could get the dual iris technology to work dynamically. If so, on bright scenes, both Irises would be fully open, the native CR performance would be worse at that point but the scene would be dominated by ANSI CR anyway. As the APL dropped, the dual irises would start to close until at the bottom, you would have them at their minimum apertures. The sharp 20k in that case acheives an 8k:1 on/off and on/off would dominate ANSI at those APL levels. Your total contrast ratio for the projector would be fairly high as well.


The benefits would be a much higher dynamic contrast ratio than the projector was capable of in any iris position originally and a much higher usable contrast ratio for low APL scenes when compared to a projector with a dynamic iris that only changes the light level.

If I recall correctly, Mark Petersen's work on the Sony dynamic irises showed that they made no difference to contrast until you got a very dark scene, around 5 APL and below if I recall. If this is correct, then compared to a fixed iris all a dynamic iris gets you are the advantages of higher contrast in a few relatively rare scenes in exchange for losing the advantages of higher contrast in the much, much more common 15-20 APL scenes.


Assuming adequate brightness, I would much rather have 4,000:1 native with a fixed iris than 30,000:1 with a dynamic iris, whose native contrast was only 2,000:1. But that's just me.
 

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It's really quite simple really. How do you release a projector, today with a real world On/Off contrast of only 8000:1? Seriously, you'd get slaughtered in the marketplace, by other machines that can legitimately claim 5-10x that.



Quote:
Originally Posted by TomHuffman /forum/post/18290591


I frankly don't have much use for dynamic irises. All they do is screw up the gamma and lower the light output only on very dark scenes, leaving the vast majority of program material unaffected.

I sort of disagree though, because for me it's those very dark scenes where contrast performance most prominently becomes a problem. My W5000 was quite pathetic in contrast performance, barely 1000:1 native, maybe 2000-2500:1 dynamic. Yet I don't think I was ever troubled by the contrast in mid-bright scenes, it was the dark scenes (where the DI kicks in) where it needed (even more than the DI's) help.


My Planar is better in every way, but I'd still like a bit lower black floor.

Quote:
A fixed iris can greatly improve native contrast at the expense of light output. If you have enough light to spare, this is a worthwhile trade-off.

There in lies the rub doesn't it. IIRC wasn't the Sharp 20K down to like 100-150 Lumens in High Contrast mode? How's that going to work on anything but a Highpower? It's definitely not going to work on a 35 sqft AT screen.

Quote:
In contrast (no pun intended), Sharp's dual iris system works fabulously well. It actually raises contrast MORE than it reduces light output. Consider these numbers for the Sharp 20K on a 100" StudioTek.

Iris Open

Peak output: 27.5 fL

Black: 0.016 fL

Contrast: 1685

Iris Medium

Peak output: 16.4 fL

Black: 0.004 fL

Contrast: 4014

Is that high lamp? And what about aging? After a few hundred hours you'd be down to like 5ftL in high contrast mode. What good is CR if it's that dim?

Quote:
For those who prefer the DLP look, this iris system could do wonders for their contrast performance. I am thinking of projectors like the Samsung, Runco (formerly Planar), and Vivetek (and others) LED units that have native contrast near 3000:1. With a Sharp iris, they would provide approximately 7000:1 with adequate light output.

Depends on your definition of adequate, you could probably hit 7000-8000:1 with something like the Planar, but you'd cut the light down to
 

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Discussion Starter · #8 ·

Quote:
Originally Posted by stanger89 /forum/post/18295551


It's really quite simple really. How do you release a projector, today with a real world On/Off contrast of only 8000:1? Seriously, you'd get slaughtered in the marketplace, by other machines that can legitimately claim 5-10x that.

I think that you are moving back and forth between two meanings of contrast without distinguishing them. The only displays I know of that can boast significantly more than 8000:1 native contrast are the JVC projectors and the Pioneer Kuro plasmas. That's it. Two displays. The Kuros are in the 30,000:1 range and the RS20 is about 40,000:1. Of course, if you are referring to dynamic contrast, then how about infinity? All the LED projectors have to do is shut the LED off when receiving a 0% stim signal and you have infinite contrast. This kind of statistic is a great marketing tool, but virtually meaningless for real-world images.

Quote:
Originally Posted by stanger89 /forum/post/18295551


I sort of disagree though, because for me it's those very dark scenes where contrast performance most prominently becomes a problem. My W5000 was quite pathetic in contrast performance, barely 1000:1 native, maybe 2000-2500:1 dynamic. Yet I don't think I was ever troubled by the contrast in mid-bright scenes, it was the dark scenes (where the DI kicks in) where it needed (even more than the DI's) help.

If you see no downside to 1000:1 in average scenes, then we'll just have to agree to disagree.

Quote:
Originally Posted by stanger89 /forum/post/18295551


There in lies the rub doesn't it. IIRC wasn't the Sharp 20K down to like 100-150 Lumens in High Contrast mode? How's that going to work on anything but a Highpower? It's definitely not going to work on a 35 sqft AT screen.

No. Greg Rogers measured the 20K in High Contrast mode as having 402 lumens in high lamp mode. Mine measured 344.

Quote:
Originally Posted by stanger89 /forum/post/18295551


Is that high lamp? And what about aging? After a few hundred hours you'd be down to like 5ftL in high contrast mode. What good is CR if it's that dim?

No good at all. You are arguing against a position I never stated. I use the Medium Iris mode. This maintains adequate brightness (10 fL or greater) on my 100" StudioTek for over 700-800 hours @ 4,000:1 native.

Quote:
Originally Posted by stanger89 /forum/post/18295551


Depends on your definition of adequate, you could probably hit 7000-8000:1 with something like the Planar, but you'd cut the light down to
 

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I probably wasn't quite as clear as I could have been. What I was trying to say was that a dynamic dual iris system would be much preferable than a single iris system that only modulated light output.


If you took the Sharp 20k as an example. It has 42.9ftl with both irises wide open. The native on/off CR at this position is 1900:1. If you applied a multiple of 3 for a normal single dynamic iris that only modulated light output and didn't change the on/off CR other than by changing the light level, you would get a CR of 5,700:1 and the attendant consequences of a dynamic iris.


If however, you made the dual iris system dynamic, you would increase the contrast ratio to 14,300:1 (42.9ftl/.003ftl Iris wide open/irises closed) and would have an on/off CR in low APL scenes where on/off dominates of 7,260:1. This would limit the amount of brightness compression in dark scenes and would allow more flexibility in the range of the iris that only modulates light output.


If you were to cut max light ouput to 1/3, which would be the equivalent of a dynamic iris increasing total on/off by a multiple of 3. You would take the brightest white down to 14.3ftl with a Sharp 20k. But, since you would be using the 2nd iris as well that allowed you to get 7,260:1 at that light level, your black level would be .00197ftl vs .003ftl. This is what I mean by giving you more flexibility in the range fo the light modulating iris with a dynamic dual iris system.


You would end up with all the benefits of a dynamic iris (higher overall on/off CR) as well as less of the downsides (brightness compression in low APL scenes) and the ability to go to a darker black than with either no dynamic iris or a standard light modulating dynamic iris only.
 

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Quote:
Originally Posted by TomHuffman /forum/post/18295904


I think that you are moving back and forth between two meanings of contrast without distinguishing them. The only displays I know of that can boast significantly more than 8000:1 native contrast are the JVC projectors and the Pioneer Kuro plasmas. That's it. Two displays. The Kuros are in the 30,000:1 range and the RS20 is about 40,000:1. Of course, if you are referring to dynamic contrast, then how about infinity? All the LED projectors have to do is shut the LED off when receiving a 0% stim signal and you have infinite contrast. This kind of statistic is a great marketing tool, but virtually meaningless for real-world images.

I said "On/Off" for a reason, yes I'm including dynamic (though I threw out "legitimate" to eliminate the infinite BS). The JVCs (RS25) can hit 50K, I think Epson's can hit 30K, even it's more direct competition can hit 15k (Planar) to 20k (Runco Q750i). Why shouldn't I include them, I was talking about "the market" with that remark. You're going up against JVCs, Sony's, Runco's, Sim2's that can all hit 5-digit sequential contrast.


Do you not agree that (save for the very few well informed like some here) a projector released today with a contrast rating of say 10,000:1 would not be laughed out of the market?

Quote:
If you see no downside to 1000:1 in average scenes, then we'll just have to agree to disagree.

We probably will, but yes, the places I see improvements in contrast with the Planar over the BenQ are in the very low APL scenes.

Quote:
No. Greg Rogers measured the 20K in High Contrast mode as having 402 lumens in high lamp mode. Mine measured 344.

On a new lamp or old? I thought for sure Darin or someone had posted 20k measurements (probably on an "old-ish") lamp that were in the 200Lumen ballpark.


[QUTOE]No good at all. You are arguing against a position I never stated. I use the Medium Iris mode. This maintains adequate brightness (10 fL or greater) on my 100" StudioTek for over 700-800 hours @ 4,000:1 native.[/quote]


Fair enough, I thought you were looking for the 8K:1 native of High Contrast mode.

Quote:
Again, no. The dual iris in the Medium mode more than doubles contrast while dropping light output by about 40%. GR measured the Planar at 612 lumens. The native contrast is about 3000:1. A dual iris would result in about 7000:1 native @ 350 lumens.

350 when new, figure that in half after a couple hundred hours and we're back to that sub 200Lumen brightness again.

Quote:
You are confusing average luminance with APL. Charles Poyton weighed in towards the end of that thread claiming that the average APL of broadcast was 50%, but that average luminance was 18%. Home video content was roughly 14%. I was seeing median APL in the low 20s for the films I sampled. Since I am not clear about how to convert APL to average luminance, I won't make any claims about that. I'm happy to accept Poynton's estimation of 14%.

You're right, I was probably being too sloppy with my terms in this thread. The term I think we settled on in that thread was "Average Display Luminance", that being the average brightness on the screen (calculated using an assumed gamma curve). This is to map directly to the measurements Mark P did.


As you pointed out, Mark's data showed that DI's start to kick in below 5% average display luminance. The data we gathered from a few films showed they are much "dimmer" than many imagine, for example Raiders of the Lost Ark, about 50% of frames are less than or equal about 5% average luminance on screen.
 

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Discussion Starter · #11 ·

Quote:
Originally Posted by stanger89 /forum/post/18296416


I said "On/Off" for a reason, yes I'm including dynamic (though I threw out "legitimate" to eliminate the infinite BS). The JVCs (RS25) can hit 50K, I think Epson's can hit 30K, even it's more direct competition can hit 15k (Planar) to 20k (Runco Q750i). Why shouldn't I include them, I was talking about "the market" with that remark. You're going up against JVCs, Sony's, Runco's, Sim2's that can all hit 5-digit sequential contrast.


Do you not agree that (save for the very few well informed like some here) a projector released today with a contrast rating of say 10,000:1 would not be laughed out of the market?

That's a marketing issue rather than a technical one. I guess that I have no opinion about that at all, and since I am not in the business of selling projectors I don't really much care.

Quote:
Originally Posted by stanger89 /forum/post/18296416


On a new lamp or old? I thought for sure Darin or someone had posted 20k measurements (probably on an "old-ish") lamp that were in the 200Lumen ballpark.

Your beef seems to really be with UHP lamps. Put a dual iris on a LED unit and this is no longer a problem.

Quote:
Originally Posted by stanger89 /forum/post/18296416


As you pointed out, Mark's data showed that DI's start to kick in below 5% average display luminance. The data we gathered from a few films showed they are much "dimmer" than many imagine, for example Raiders of the Lost Ark, about 50% of frames are less than or equal about 5% average luminance on screen.

I am really skeptical of that figure. Poynton's claim that typical films on DVD and Blu-ray have a 14% average luminance and the APL numbers I got from Raiders suggest that it is not unusually dark, like the way that Alien is, for example. It did seem to have a higher dynamic range than many films. There are a lot of very bright scenes in it and a lot of very dark scenes.
 

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Quote:
Originally Posted by TomHuffman /forum/post/18297329


That's a marketing issue rather than a technical one. I guess that I have no opinion about that at all, and since I am not in the business of selling projectors I don't really much care.

Your OP was why has no one licesned the technology, and my guess is "marketing" has a lot to do with it. As I said, how do you bring out an 8000:1 machine (that's really only got usable brightness in the 4000:1 configuration) in a market where everyone else is selling (legitimate or not) 50,000:1, 80,000:1, 200,000:1 machines, where even your more direct competitors (other DLPs) are 2-3x the contrast.


You and I and others on this forum might be savy enough to really weigh the benefits of both approaches (eg I don't put much if any stock in LCD's DI approach), but we're not enough of the market to make an impact.

Quote:
Your beef seems to really be with UHP lamps. Put a dual iris on a LED unit and this is no longer a problem.

My issue is with low brightness and cost, I don't really care what the technology is. I've got a 35 sqft AT screen (and I'd like a bigger one if I ever get a larger HT in the future), which means I need to bank on at least say 400 lumens for the long haul. Unfortunately from what I've been able to gather, that's asking a lot of any of these high contrast, dual iris machines. I thought about a used 20k before I got my Planar, but research led me to conclude it wouldn't be able to achive adequate brightness with good contrast on my screen.

Quote:
I am really skeptical of that figure. Poynton's claim that typical films on DVD and Blu-ray have a 14% average luminance and the APL numbers I got from Raiders suggest that it is not unusually dark, like the way that Alien is, for example. It did seem to have a higher dynamic range than many films. There are a lot of very bright scenes in it and a lot of very dark scenes.


I actually got 9.63% average luminance for Raiders, here's the histogram:



And there are two clear peaks, which also matches your observations of lots of very bright (30% ADL is quite bright) and rather dark scenes.


I should go back and run some more movies through that script and see what we get
 

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Discussion Starter · #13 ·

Quote:
Originally Posted by stanger89 /forum/post/18298134


Your OP was why has no one licesned the technology, and my guess is "marketing" has a lot to do with it.

That may be. Marketing trumps technical values all of the time (Kuro, anyone?).


Something I should have made more explicit in my original post is that I really think that we have reached a crisis in this regard. The claims manufacturers make about contrast are so transparently phony, so disconnected from any indication of real performance, that I think consumers are on the verge of being victims of fraud.


This industry desperately needs something like RMS, which the audio community adopted a couple of generations ago as a way of dealing with just this problem. Amplifier manufacturers were advertising wildly inflated specs on power output. The RMS rating forces them to specify power rating with a specified number of channels driven at a specified frequency range at a specified level of distortion. Display contrast should have a similar metric. On/off contrast at a specified:
  • white balance
  • gamma
  • gamut

The spec should also clearly distinguish between dynamic contrast and native contrast. Until we get this consumers will be in the dark as to what type of performance displays are capable of.

Quote:
Originally Posted by stanger89 /forum/post/18298134


My issue is with low brightness and cost, I don't really care what the technology is. I've got a 35 sqft AT screen (and I'd like a bigger one if I ever get a larger HT in the future), which means I need to bank on at least say 400 lumens for the long haul. Unfortunately from what I've been able to gather, that's asking a lot of any of these high contrast, dual iris machines. I thought about a used 20k before I got my Planar, but research led me to conclude it wouldn't be able to achive adequate brightness with good contrast on my screen.

I am not advocating any particular projector. Rather, I am advocating a particular technology. The Sharp, for example, has a 220-watt bulb. Give it a 300-watt bulb like the Samsung has and it would obviously be a lot brighter. Also, as I indicated, a dual iris system is particularly attractive for some of these DLPs--like the Planar--that have relatively high native contrast to begin with, much higher than the Sharp. Give the Planar another 100 lumens and a dual iris and that's a killer unit. The next generation of LEDs should be able to provide 400-lumens for thousands of hours with 7000:1 native contrast if they had a dual iris. They are close now.

Quote:
Originally Posted by stanger89 /forum/post/18298134


I actually got 9.63% average luminance for Raiders, here's the histogram:



And there are two clear peaks, which also matches your observations of lots of very bright (30% ADL is quite bright) and rather dark scenes.


I should go back and run some more movies through that script and see what we get

That sounds more like what I would expect. BTW, what's the math you use for determining ADL?
 

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Quote:
Originally Posted by TomHuffman /forum/post/18298808


That sounds more like what I would expect. BTW, what's the math you use for determining ADL?

It's all detailed in the other thread, basically on a per frame basis (using avisynth) gamma "compensating" the frame (to approximate what would be measured on screen), then using a utility to calculate the average luminance of that frame and logging it to a file.
 

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Discussion Starter · #15 ·

Quote:
Originally Posted by stanger89 /forum/post/18299727


It's all detailed in the other thread, basically on a per frame basis (using avisynth) gamma "compensating" the frame (to approximate what would be measured on screen), then using a utility to calculate the average luminance of that frame and logging it to a file.

I have the avisynth and dgindex stuff. All you say about incorporating gamma coding is "I posited in the DI thread that the Levels command could be used to apply display gamma to the above script to convert from %stim to APL."


I don't know what thread you are referring to, nor do I see how to incorporate a Levels command.
 

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I have a 1080UB w/ a single dynamic iris. I really could never detect a significant difference in picture quality with the iris enabled/disabled. After a while I just turned it off since the Epson implementation sounded like a coffee perculator.


After having owned a DLP projector previously, I guess I am wondering if there is much life left in DLP. RP sets are dead and the FP market is still an enthusiast market which seemed to be moving away from DLP also in favor of improved LCD and LCOS technology.


Not saying that having a dual iris system is a bad idea on a DLP, I just don't think there is much of market for it considering it would probably be competing with LCOS projectors that are capable of high native CR without the aid of an iris system. I just think the time may have passed DLP.
 

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Discussion Starter · #17 ·

Quote:
Originally Posted by Toknowshita /forum/post/18300272


I have a 1080UB w/ a single dynamic iris. I really could never detect a significant difference in picture quality with the iris enabled/disabled. After a while I just turned it off since the Epson implementation sounded like a coffee perculator.

That's been my experience as well.

Quote:
Originally Posted by Toknowshita /forum/post/18300272


After having owned a DLP projector previously, I guess I am wondering if there is much life left in DLP. RP sets are dead and the FP market is still an enthusiast market which seemed to be moving away from DLP also in favor of improved LCD and LCOS technology.


Not saying that having a dual iris system is a bad idea on a DLP, I just don't think there is much of market for it considering it would probably be competing with LCOS projectors that are capable of high native CR without the aid of an iris system. I just think the time may have passed DLP.

I am not sure about this. This is another marketing issue. My guess would be that LCoS and LCD will own the bulk of the front projector market, but that there will still be a smaller, but meaningful, market for DLP front projectors for those who prefer the DLP look, much like plasma displays have a minority, but healthy, market share in the flat panel market.


I guess I also question how meaningful native contrast levels above 7000:1--which is easily achievable will a dual iris DLP--will be for the average consumer beyond the wild marketing claims about 80-million-to-one or whatever.


I am beginning to think that I misnamed the thread. It could very well be that this is a bad idea because of any number of marketplace reasons that I won't pretend that I can predict or even entirely understand. What motivated my original post was what I think is a disturbing trend among the remaining DLP manufacturers--Optoma, Vivetek, and BenQ, especially--to rely on dynamic irises that aren't very well implemented on machines that don't have great native CR. I would argue that these projectors would offer better images if they dumped the dynamic irises and installed fixed dual irises instead. The Samsung DLP, which has a 300-watt bulb, would also be a great candidate for a dual iris, as would the new LED DLPs.
 

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Quote:
Originally Posted by TomHuffman /forum/post/18298808


Give the Planar another 100 lumens and a dual iris and that's a killer unit.

IMO the Planar (8150) needs a better dynamic iris and better lens, I never had a problem with the lumens on my 10' 2:35 hi power screen, if you guys remember it was toooo bright, In the end I ended up getting a 10' Carada 2:35 screen to cut down on the light but then the dynamic iris drove me crazy, a friend of mine also spotted the fact that the overall sharpness and clarity was not in the same league as my previous 11S2, hence the sale of the Planar and purchase of 15S1 with long throw option. 8150 is a nice platform they just need to build on it then it will be a "killer" unit
 

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Discussion Starter · #19 ·

Quote:
Originally Posted by funlvr1965 /forum/post/18301131


IMO the Planar (8150) needs a better dynamic iris and better lens, I never had a problem with the lumens on my 10' 2:35 hi power screen, if you guys remember it was toooo bright, In the end I ended up getting a 10' Carada 2:35 screen to cut down on the light but then the dynamic iris drove me crazy, a friend of mine also spotted the fact that the overall sharpness and clarity was not in the same league as my previous 11S2, hence the sale of the Planar and purchase of 15S1 with long throw option. 8150 is a nice platform they just need to build on it then it will be a "killer" unit

This is precisely why I favor dumping these dynamic irises entirely in favor of a good fixed dual iris. All you have to do is use a 250-watt+ bulb or perhaps LED to get adequate brightness.
 

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Quote:
Originally Posted by funlvr1965 /forum/post/18301131


IMO the Planar (8150) needs a better dynamic iris and better lens,

Well just about anything could use a better something....

Quote:
I never had a problem with the lumens on my 10' 2:35 hi power screen, if you guys remember it was toooo bright, In the end I ended up getting a 10' Carada 2:35 screen to cut down on the light...

I'm not surprised, my 8150 is plenty bright on my 9'+ scope screen. That said, I think a 40% drop would take it out of the running.

Quote:
...but then the dynamic iris drove me crazy,

Mine's fine for me.

Quote:
...a friend of mine also spotted the fact that the overall sharpness and clarity was not in the same league as my previous 11S2, hence the sale of the Planar and purchase of 15S1 with long throw option. 8150 is a nice platform they just need to build on it then it will be a "killer" unit

Isn't the 11S2 like 2x the price of the Planar too?

Quote:
Originally Posted by TomHuffman /forum/post/18301374


This is precisely why I favor dumping these dynamic irises entirely in favor of a good fixed dual iris. All you have to do is use a 250-watt+ bulb or perhaps LED to get adequate brightness.

Just curious have you seen the Planar? Or what DI's have you seen that you don't like? I'd be curious to your reaction to the Mico/Lumis/Q750i.
 
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