PANASONIC PT-RZ470 FULL HD LED LASER - Page 2

Just a question on contrast ratio:

My understanding was DLP projectors produce nicer blacks compared to LCD since transmissive techonology can never totally block out light.

The constrast ratio given for the PT-RZ470 is absolutely horrible compared to LCD projectors, which I've seen speced at up to 200,000>1

Or is producting good, deep blacks something totally different than contrast ratio?

I was advised on a different post to wait for this technology rather than buy a decent 3-LCD projector now, but I'm a litle uncomfortable since I hate color-wheel DLP with passion (I was a friend's DLP in 2005 and it was totally unwatchable because of rainbows) and the specs on this unit don't look great even if they've fixed the rainbow problem.

Wait 2-3 months or 2-3 years?

You need to remember that those are highly inflated numbers, Real on/off contrast numbers of those LCD projectors when using the iris will max out around 20000:1. Numbers given for contrast ratio will vary from company to company. How truthful they are about real world results will vary as well. If you look at companies like Runco or Sim2 they usually will give VERY accurate CR numbers where as companies like Epson, Mitsubishi, JVC, Panasonic, and Sony usually inflate the numbers substantially.

I don't mean to sound rude, but you played into their game exactly how they wanted it. They played the numbers game and you believed them. I would imagine that this new Epson will reach right around 20,000:1 with the new LED/Laser light system solely based on how much better DLP is with native contrast and how quickly these new light sources can be fully turned off.
Edited by Seegs108 - 6/17/12 at 11:22am

The 200,000:1 number is with in iris. 20,000:1 without an iris would actually be very good.

The problem with an iris is when you get a scene with really bright parts and really dark parts. A specific example I can think of is near the beginning of the movie "2001: A Space Oddesssey" Right after the bone thrown into the air turns into a spaceship, you see the earth from space. The camera then pans away from the earth into a dark starscape. Ideally as the pan happens, you will see the detail of the earth, and you will also see the stars at the same time as the scene pans. With an iris, however, what you initially see is the details of the earth (the iris is closed), but you don't see any stars (the blacks are crushed). As the camera pans towards the darker starscape, the iris will open. What happens here is the stars become visible, but the earth turns really bright, and the detail of the earth is lost (the whites are crushed) as the iris opens up.

So in this particular scene (or any other scene with both really bright and really dark areas within the same frame), the 200,000:1 projector with an iris will perform much worse than a 20,000:1 projector without an iris.

When samsung had their led dlp TV's out, i had the 61" version. There was still rainbows present. In fact they annoyed me enough to sell it 3 months after getting it. it was a great TV other than that.

I've had the Samsung 67" LED RPTV and have never seen a rainbow. Ha! It does pay to be 71!

I take it LED DLP TVs are colorwheel-less designs too. So I'd still see rainbows with these Laser+LED designs?

Quote:
Originally Posted by N8DOGG

When samsung had their led dlp TV's out, i had the 61" version. There was still rainbows present. In fact they annoyed me enough to sell it 3 months after getting it. it was a great TV other than that.




I still have my 61" LED Sammy and have never seen a rainbow. Bought my first DLP projector with a color wheel couple months ago, BenQ W7000 and I can see them, more so in 3D actually if I shift my eyes. But never on the Sammy even trying to dart the eyes. People's sensitivity to them clearly varies.

I stand corrected; I didn't realize the 8100 was a HT model.

Nevertheless it's CR makes it a nonstarter for many of us.

Maybe on projectors with poor iris implementations. On projectors with good iris implementations, like my Planar 8150, the iris is basically transparent for real world content. The only time I notice the iris on my 8150 is with text overlays. As a reference, I had a BenQ W5000 prior to the 8150 and it's iris implementation, while I'd rate it "good" was not as good as on the 8150.

What you will see with a good iris implementation, specifically vs a projector with higher native contrast, is that black either won't be as black if there's something bright in the scene, or that brights aren't as bright.

As i posted here several times, i own a Runco LED projector with Luminus Devices R/G/B LEDs and i can still see rainbows, although they are extremely rare and exceedingly fast to be really noticed; In exchange for that i get an incredibly detailed picture without any panel misalignment nor lens chromatic aberration, the highest native ANSI contrast level ever measured by Projector Central.com as well as other A/V publications, and those LED colors are something that must be seen in person to understand why everyone becomes enthralled with LED light sources after awhile, never mind their color oversaturation or not.
BTW, those round Luminus Devices mentioned above cannot be used for front projection panel illumination for the simple reason that native 16x9 DLP, LCD and LCOS micro-displays are rectangular, not round, and ideally the shape and size for both items should be matched as close as possible... AFAIK, the PT-120 Phlatight R/G/B LED chipset from the company is still their most powerful available which can be used for video projection application.
On the other hand, i am impressed with Panasonic for finally releasing projectors such as these using a combo of red + blue LEDs and green Laser, unlike Casio and that contraption of red LED + blue LED with attached color wheel with green phosphor and i imagine dichroic mirrors to separate the color green emanating from the blue LED after passing through the color wheel; I wonder what is the failure rate for such arrangement as well as how accurate the green color is, especially compared to the other colors afforded by those LEDs.
For Panasonic to claim DLP native contrast ratio of 20.000:1 is wishful thinking and marketing hype; From reading uncountable reviews of front projectors, only LCOS panels from JVC and some recent SXRD panels from Sony can claim such high numbers; The best and only native contrast ratio i've seen for a DMD chip from Texas Instruments that even approached 10.000:1 was for a test report on a Sharp pj a couple of years ago, and that was because the lens iris was clamped down so much that the onscreen brightness was only about 8 ft-L.

O ya for sure. I cannot even stand to be in a room with a dlp 1 chip projector, blah!!! When I bough my sammy, there were 2 things I didn't like, the screen door effect on pure white was a bit annoying but not that bad and the fact I could see smearing all over the place. There was a thread with a poll on AVS when it first came out and I was pretty surprised that it was something like 35% could see rainbows on their new sets. Though it did cut down the effect by 80% vs a projector or a mits set.

The youtube video linked near the top has a few shots of the connectors on the back, If the ethernet jack can do video that would be amazing because thats a lot easier to run than a DVI cable, and most of us have that run to our PJ location already. DVI would be great too though, its not like our video cards have ethernet out.

the link in the first post details this... they will also be selling a switch with HDMI inputs and 'HD BaseT'(cat 5e/6) out...ET-YFB100 seems like a nice solution compared to long runs of HDMI or DVI.

It looks like HDBaseT is theoretically capable of carrying 120hz content. But the specs for both projectors as currently listed on the panasonic website do not show scan rates higher than the standard 1080p@60Hz.

On an unrelated note that may be of interest to those reading this thread, Cree (a leading LED manufacturer) has been selling 3LED LCD projectors for a long time now, here is the thread:

http://www.avsforum.com/t/1307577/cre-x1000-worlds-first-3-led-3-lcd-1080p-projector-anybody-heard-of-these-guys

http://www.projectorreviews.com/press-releases/?p=937 ... BENQ also has a laser machine coming.

We really need someone like Optoma to come along with something like an LED/laser version of the HD82/83/87 for sub-£3k. That'd be a market-changer.

Indeed, at the moment it would be so at sub-£5k.

Steve W

Was shown a demo of this at Infocomm a few days ago. Colors were a little washed out, and the white had a yellow tint to it, but according to the rep this would be fixed before release. He also said native contrast would be 20.000 - 1. I asked if that was the actual number or if it was pulled out of thin air, but he assured me that it was true. I have my doubts.

Any thoughts on black level? A native contrast this "high" would suggest very good black level. The first JVC's were around this number I believe, and they're always at the top of the black level list (even the 'old' ones).

He probably didn't know the difference between native and dynamic.

Dynamic contrast is contrast that a projector could achieve with the help of an Auto Iris.

I believe there is no Auto Iris in the RZ470. If it has, the contrast should be higher than the 50,000:1 ratio achieveable on the BenQ W7000 and Optoma HD87, both of which use an Auto Iris.

In the absence of light, ie with the LED's and Laser in switched-OFF mode, the contrast on a DLP which is reflective, could be as good as a Plasma or a CRT.
Edited by Haw - 6/20/12 at 4:47am

FWIW, this is coming from a pretty big DLP fan...

It could be, but it's not likely, the best DLPs out there, like the Lumis are only barely in the 20k:1 ballpark with the help of a dynamic iris. 10k:1 is at the outside limits of what's possible for native contrast from DLP and that's with some very aggressive (read, very dim) fixed iris configurations like the Sharp 20k or Marantz 11S2.

Yeah, and they don't come anywhere close to 50k:1 in real life. IIRC My BenQ W5000 was about 1000-1500:1native and 2300:1 or so with the iris enabled.

Sort of, except you can only brighten/dim the whole screen/image at once so it's not like a plasma or CRT where you can have enormous intrascene (static) contrast. The LED DLPs like the Runco Qx50 and Truvue Vango do LED dimming, and can completely turn off for a fade to black, but that only works for completely black frames, if there's anything above black in the frame they can't turn the LEDs off. And of course this is Panasonic we're talking about, who's projectors are usually luckly to hit 10% of the contrast they claim in a usable mode.

What stanger said. I remember someone telling me the best way to test one of these LED DLP pjs would be to have one pixel on. If you do that, then the on/off is around 5k to 1 IIRC.

WXGA projectors?
Edited by Snipe3000 - 6/26/12 at 3:31am

Well, any one have ideas on the price?

viewsonics 1080p led laser will be out soon(1200 lumen)-most will have a led/laser 720p and the benq laser color wheel 720p biz pj soon.

optoma has 2 ready for end of summer a 720p and 4:3-HT pjs will come after they make some money in the biz pj area

http://www.optomausa.com/products/detail/ZW210ST

Agreed... No way to know for sure. Even current LED DLP's have some instances of rainbow. Granted fewer chances but it all depends on the specific viewer.