Panasonic PTAE7000/ AT5000 - Page 8

I always thought it was electronic - but I guess not (granted this is a very old link, from the 1000, so something could have changed - and I certainly don't see how it would be possible to "only apply to specific areas" like I thought I heard them mention if this were the case):

http://www.panasonic.com/business/pr...nter/lc_ss.asp

The biggest complaint people have ith installations and calibrations is the picture isn't bright enough. So most installers just opoen the iris to its widest position.

Nut it is there and installers and end users can pretty much maske the trasde offs that result.

On off contrast is just one of many factors and I really think its specious to state that is the only type of cotrast that makes a difference. If that's what one thinks, that it is the only type of contrast that's important, let's just say that's your opinion. In my opinion, I think manytypes of contrasts are important and all specific types are just an articial measurement pasrameter that don't tell the whole story.

Yeah, like the Panasonic single chippers look, that's quite a square box, so I am in the industrial look camp, I guess.

Just watch David Hamilton films.

No reflective LCDs?

To clarify, I am speaking in terms of the numbers the Manufacturers give us to compare, not actual resulting intrascene contrast.
Sorry, I don't mean to sound argumentative, just clarfiying...

Some people forget that how well the IRIS works in real world viewing on a projector isn't related to the dynamic contrast that these MFR's claim, but its more related to the way it was programmed in how it senses the amount of light being output by a particular scene and the contrast of that scene.

If you have a projector capable of 5000:1 native, and say you were displaying a very bright scene in the sun, then you went to immediately an all black space scene, even if the IRIS truely closed down to create the effect of 100,000:1 very quickly, well under normal fL conditions (12-16), the white peaks / stars would suddenly look way too dim to our eyes. At some point the three types of measured / predictive contrast (Native, ANSI, and dynamic) do predict a MAXIMUM type scenario of what the capabilities are, and a low Native Contrast will directly conflict with a higher dynamic contrast in the sense that a projector with a lower Native Contrast cannot keep the white levels high enough in the resulting intrascene contrast. So while the dynamic contrast from the IRIS shifts the overall brightness of the image lower, the Native fails to keep the white levels at the proper intensity because the IRIS is reducing the total light output.

What I mean is, even if a projector were truely capable of some ridiculously high dynamic contrast and it could do it quickly, then it wouldn't matter if the native were low, there is a theoretical conflicting limit between the two numbers.

Now if you went from an already dark scene to an even DARKER scene, then you couldn't acheive that kind of contrast from an IRIS anyhow.

I'm not saying dynamic contrast itself is worthless, just that the numbers they give us are. It is a cheat measurement, 1 to 3 seconds might be a reasonable maximum to check maybe over scene transitions, but they leave it running for too long.

Also the garbage in/garbage out rule applies, some camera men don't give us enough contrast in a scene to even matter.

Regarding the IRIS issue, I am just saying that most IRIS's I have calibrated are not optimal at their maximum settings or most hardcore positions, it makes things like the stars look gray on some scenes when the IRIS closes down too much. I agree that the IRIS thing is subjective at least to a point.

Sorry, I seem to be extra wordy today, just can't spit out short sentences, I'll work on it

No, the smoothscreen cannot be turned off. This question and discussion is talked about every year. Panasonic likes Smoothscreen and has no desire to take it off. The question is asked every year.

As for dust blobs, LCD projectors cannot be completely sealed so although they put filters in the projectors to guard against this, this is no way to guarantee that it cant happen.

I would say this is true for every LCD projector out there, but I am sure someone will tell me about one projector that is different

The Panny lit describes this business model as "hermetically sealed". I don't think that's actually true, since it does have an air filter, with an interesting rolling mechanism, but nonetheless I thought it might be of interest to some:

http://www.panasonic.com/business/pr..._demo/arf.html

"Anti-Dust Design - Re-engineered airflow path creates a cabinet that hermetically seals off the projector interior."-

http://www.panasonic.com/business/pr...ries/index.asp

I wonder if there are any liquid cooled pjs like on some computers?

The AE7000U has a +/- horizontal lens shift of 26%, so the 3" offset shouldn't affect most installs. Another interesting feature that no one (that I've seen) talk about is the 2D to 3D conversion. Any source sent on HDMI/Component will be able to be seen this way. We saw a demo yesterday where The Thin Red Line was shown. Standard BR player, and the conversion was good. Images didn't necessarily pop out, but rather there seemed to be added depth. It might not be for everyone, but I think there will be plenty of people interested in watching NFL games this way.

Yes, there are quite a few liquid cooled pjs out there. Panasonic has the most from what I've seen. Their "D" series models especially (PTD6000US is one example)

All of the Chi-Lin OEM LED projectors eg SIM2 Mico, EE truview vango, Wolf, etc. are all liquid cooled.

My PT-AE4000 is due for an upgrade, but only looking for 2 things.

Darker black level, WISH they would spec this!
and
HDMI Auto lip sync, the AE4000 lip sync is all over the place when you change 24p, 60p, and frame creation modes!

My receiver has auto lip sync but does nothing unless the projector does.

If the PT-AE7000 doesn't have these 2 things I'll be shopping another brand..

Contrast ratio specs are a joke, since they don't spec black level.

I would even go out on a limb and even say that there is a theoretical limit to the usefulness of IRIS's in how much dynamic contrast they produce in relation to a projector's native and intrascene contrast limitations.

If you were watching a projector at 15fl and the IRIS reduced the lumen output to 1/3rd, then the brightest your star could possibly be is 5 fL, but due to contrast limitations it would be even darker than that, so you'd essentially be looking at a black hole with no stars in it way before you got anywhere near the numbers they are claiming. This is of course pseduo numbers since we know the real contrast from an IRIS isn't exactly linear, but close enough.

Since the IRIS reduces overall light output, then we can't go too dark or else we can't see the image anymore!

So even if their dynamic contrast numbers were correct, it would only work if there was no bright areas in the scene, and by no bright areas I mean only if our end goal was pitch black nothingness.

Sorry to sound like a broken record, but does this projector have vertical stretch in 3D? In other words, can one watch a 3D movie shot in 2.35 with an anamorphic lens?

I think no vertical stretch in 3D, you will need a Limagen mini for that.

The DI discussion does not reflect dynamic gamma increases to boost the high end of the IRE scale to offset the cutting down accross the board of the iris. You can't boost too much, however, because one would suffer brightness compression, but your star points will be plenty bright in that one example.

BTW. No pricing yet asvailable on the Panny. No ship date available. So no distributer, let along dealer, knows anything other than MSRP.

How was the 4000 for Dust blobs? My Mitsubishi LCD had them all the time. I used to take it apart relatively often to clear it. The filter just couldn't keep them out of the light path.

I haven't dealt with DB's since going DLP & LCOS. Not sure i'd want to see them again. some were huge on my 142" screen.

This projector does sound exciting, especially if they can get it to street around 2.5 -2.8 max.

My PRO-FPJ1, (D-ILA/LCOS), although having a so-called sealed light path, still get some dust blobs, although nowhere as severe as my AE-3000U. However, because it's sealed, I can't clean it as easily as the AE-3000U. Both are PITA, I sure wish they use HEPA-grade filter so there is no dust blob issue anymore.

On/Off Contrast = white level / black level. If you have the CR and a white level (which depends on your screen size) you can always calculate black level.

This is not true. Every contemporary DI system has some kind of dynamic video level adjustment system which boosts the level of bright objects while the iris lowers the overall scene level. Panasonic's is called Dynamic Gamma IIRC. DI do increase intrascene contrast using said method, within limits defined by the native/static panel contrasts.

You mean you have to manually adjust for lip sync per source? WTH? Is that common?

Videohacker is partially correct. CR spec is pointless, however the main reasoning of the uselessness is due to there is no standard in calculating CR.

I'm a little bit confused by how the memory zoom feature works. Does it basically just zoom out to display the native aspect ratio, say 2:35:1 to fit on a scoped screen and then zoom in for 16:9?

If this is the case, the "black bars" on a 2:35:1 movie would simply spill over the screen edges of a 2:35:1 screen right?

Don't all projectors do this, albeit maybe not with motorized zoom/memory setting?

I am probably going to purchase this when it comes out along with a 2:35 screen and i just want to make sure I understand how it works as this is my first projector.

Thanks

You are partially correct, all projector can do this. However, it's not as simple as just changing the zoom. By changing the zoom you also have to change the focus and also the location of the image within the projected area.

Furthermore, the AE4000 allows the use to mask the 16:9 area further so the light spill is even less apparent.

Quote:
Originally Posted by sharp360
I'm a little bit confused by how the memory zoom feature works. Does it basically just zoom out to display the native aspect ratio, say 2:35:1 to fit on a scoped screen and then zoom in for 16:9?

If this is the case, the "black bars" on a 2:35:1 movie would simply spill over the screen edges of a 2:35:1 screen right?

Don't all projectors do this, albeit maybe not with motorized zoom/memory setting?

I am probably going to purchase this when it comes out along with a 2:35 screen and i just want to make sure I understand how it works as this is my first projector.

Thanks

You are partially correct, all projector can do this. However, it's not as simple as just changing the zoom. By changing the zoom you also have to change the focus and also the location of the image within the projected area.

Furthermore, the AE4000 allows the use to mask the 16:9 area further so the light spill is even less apparent.

If the projector is centered on the screen, why would the "location of the image within the projected area" change?

For example, the screen i will be getting will be a scoped screen, so when i zoom in for 16:9, wouldn't the image stay centered and the height stay the same? Wouldn't I just loose an equal amount of width on both sides of the screen?

What does that translate to for a 13ft wide screen with 18ft throw? How does it compare to the JVC RS horizontal shift? I require substantial horizontal shift in my current installation.

IF the projector is centered on the screen on both X and Y axis, yes you won't have that problem.

But if it's only centered on the X axis, you'll have to either do lens shift to compensate the Y projected area or have a digital image shift (either on the projector such as the AE4000/AE7000 or buy a scaler that can do an image shift)

If you're in the Toronto area, PM me, I'll be more than happy to demonstrate it to you.

Do like I do. Buy some high grade filter material and make your own.

I do actually wish this worked right, but these features do not work correctly to combat reduced light output and they are more marketing terms than reality.

I was using pseudo math since we don't have real measurements in front of us. However, the issue is that the capabilities of the projector's intrascene contrast are pushed beyond the limits of its ability to retain a bright enough white level after the IRIS closes down. Eventually an IRIS decreases the white levels so much that to our eyes the scene is out of whack and too dark looking. So it's also about the peak white level in the scene when it comes to using an IRIS. That is why there are theoretical limitations for the usefulness of dynamic contrast produced by an IRIS.

I am not saying an IRIS is useless, just stating it has major limitations in respect to the claimed dynamic contrast ratios. There are sweet spots and optimal configurations for every IRIS.

You cannot sufficiently combat the light reduction while the IRIS clamps down with dynamic gamma, as the way the dynamic contrast is acheived is by the IRIS blocking light. It's a catch 22 and a contradiction. If it were able to combat it enough, then there would be no compression of white levels.

I can use a light meter and try it and measure the compressed white levels, we can also easily see it with our eyes.

I already use higher-grade air filter on ALL openings (except the air outlet) and STILL I get dust blob. It really annoys me especially because the room already uses a separate HVAC with filtered return, filtered HVAC and filtered air outlets.

I'm afraid if I block the projector air outlet it will overheat.