OPTOMA HD91 FULL LED DLP full hd 2D 3D Ready september 2013

What is this?

Hi,

in germany it is a discussino, that this chip can work for
144hz tripple flash.

it is build in the benq 1070.

Greetings

Great news. How was the contrast in HD91?

In general, does laser source help in improving contrast?

I look in the secifies at hd 25...now 20000:1 so i think the hd 91
it is gone to top this.

Ireally impressed when optoma held promise.

Greetings

I'm talking about real contrast, not declared.

Well, if you are talking native contrast then I would guess the new iteration of the .65" DC3 chip will be around 3000-4000:1 range. I am guessing the dynamic dimming of the light source will make for a better overall contrast. I presume that's how hybrids do dynamic contrast

I would bet that Optoma will do a decent job of colour reproduction and DLP with no rainbow effect is always a winner. Of all the hybrids announced, I would expect this and the 1080p Mitsubishi to produce decent results

What do you think about what I would be happy if it were actually;).
Now we have to wait on the first results of tests.

I'm really excited.

Greetings

it's good news that they are including the RF in there as well in addition to the DLP flash.

I'm curious to hear about the lens shift. Is it the standard above/below the screen or is it more HP friendly?

I highly doubt that, too good to be true. The new iteration with such a step up would have been called "DarkChip5", not just "4244 DC3".

brcause of the way DLP chips work, having it not above or nelow would really have an adverse effect on contrast. there is a reason its not done.

interesting info. It looks like Sim2 recommends a center lens / screen setup? Is the 3 chip setup different?

I'm pretty sure that slide isn't correct (hope not).

Most of the comments regarding DLP contrast relating to offset are based on TI tech docs for design of SINGLE DMD systems. I'm not sure if the issues are alleviated with a typical 3 DMD design, as I've not read them. Interestingly, there are expensive single chip DLPs that allow center mounting (e.g. the Runco x200i)... apparently, some manufacturers still think it is a reasonable tradeoff and that those buying strictly based on native on-off contrast are probably not considering DLP anyway???

I think it would be too good for a .65" DMD with high brightness and good placement flexibility, but if it was targeting bat cave performance with ceiling mount and long throw, it would be entirely reasonable... just wouldn't sell too many!

If Optoma can produce an LED/Laser version of the HD82, then that's probably me done. See you in 20,000 hours.

Steve W

I looked through various reviews of 0.65" DC3 DLP and you are right, it seems the 2000:1 range seems more realistic for native contrast

Hi,

Kraine has measured int the test of the benq 1070 a native contrast of about 4200:1.

OK now, not the champion but a doubling.
I think that can be brought out by the new techniques even more.

Greetings

Thats not native, but with lamp dimming.

Didn't say it was common... most DLP designs trade some contrast for brightness, placement flexibility and lens cost. Some here have measured the HC4000 around 3k:1. It is certainly doable, but maybe not a good design choice from a marketability standpoint.

Improved contrast is more likelly to come with true laser dlp projectors and less likely with laser+led hybrids.

There is a TI paper somewhere that sets forth how a DLP projector should be designed to maximize contrast. I have not read the paper but others in various threads have discussed it.

Many projectors including some DLP projector have been designed so that O offset is with the lens center being a lens center. this generally is the most marketable way allowing for a lens shift that allows a maximum shift to about 15% above screen top or bottom. At lot depends on the diameter of the lens with chip image edhe deterioration occuring if the shift goes beyond 5% of screen top. generally this will cause a hit on contrast. Sim2 is not big on publishing contrast specifications while non DLP projector manufacturers relesh publicizing huge on off numbers. There are trade offs And lens size enters into the equation big time. Thje most perfect image quality psition for a DLP projector regardless of one or three chips, is a fixed offset considerably above or below the screen. Next is to allow some lens shift away from that point. But doing this will severly limit the market for the product. And when push comes to shove manufsacturers say screw it, the dumb ass customer won't know any better, so lets do it at lens center and allow a huge offset range. Allow them to shift from center to say 30% above or below the screen. Its all about marketability.

Zombie 10K

The Texas Instruments paper I referred to in my last post is an Application Report, DLPA022 July 2010 entitled DLP System Optics and it primarily deals with single chip DLP projectors. It is not a casual read and one an engineer and projector designer would want to read rather than an end user.

But hidden in a careful read are the reasons why DLP projectors have followed the design paths they have and how optics enters into the equation. An offset archetecture increases contrast or rathe rlowers the black value but cause some uniformity problems and how ceratain cheap projectors with high effective F stop lens require more offset.

It explains in part the choices Sim2 made in using the desin architect it did not being constrained by a need to keep lens costs down. There is a lot in the paper and it is not a casual read.

Its contents can be used to explain some of the cost variances betwen projector design and should make some DLP fan posters here understand what they are askjing for price wise and what they are giving up by asking for wide range offsets.

In a stellar execution of my mastery of using my laptop, I take pride in posting a link to the paper

http://www.ti.com/lit/an/dlpa022/dlpa022.pdf
Edited by mark haflich - 1/31/13 at 9:34pm

Oddly enough the Planar PD8150 uses basically the exact same Telecentric Architecture depicted in figure 2 and these units yield great (some of the best for DLP) native on/off contrast ratios. It states one of the negative aspects of this design is an elevated black floor. Though, the excellent results could be through the use of the best of the best DMDs and great stray light absorption.

At least one pricey Runco does as well (x200i)... Not sure of its native contrast, but pretty sure its not below 1k:1 . So, obviously the loss of contrast can be somewhat mitigated with good design and optics... Makes me wonder just how good on/off could be with no compromises... Obviously not jvc levels, but maybe 6k:1?

There are a ton that use the light path/optics design the PD8150 started, including many current single chip LED DLPs. Runco Q750i, Sim2 MICO 50, and Vivitek H9080FD use it too. I think the internal chassis is manufactured by Delta and it seems that it is a very popular design.

You know the old saying, if it ain't broke don't fix it.
Edited by Seegs108 - 1/31/13 at 9:16pm

The highest native contrast single chip DLPs like Sharp 20K and Marantz 11S2 have a CR of about 10K:1 with clamped irises. But if I remember correctly they don't use any lensshift offset? If that's right it seems to run counter to the white-paper?

I'm afraid 6K woud be way too good. Manual says "1300:1 full-on, full-off." http://www.runco.com/downloads/manuals/X200i_manual_sep12.pdf

Reliable source gives even PD8150 only 2700:1
http://www.cine4home.de/Specials/Planar8150/PlanarFullHd.htm