Still trying to decide on screen material.

I was hoping to get an idea of the light output (foot-lamberts) that people were hoping / expecting to get off their screen, given the previously described Lumis output and their screen gains. (New bulb)

I will be getting a smallish 2.35:1 screen, 112" width. (85" 16:9 width)

I am leaning towards a Stewart graymatte with either .7 or .6 gain.

Thanks in advance for the info.

Kevin

The consensus appears to be more than 2000 lumens with a new lamp.

Just use the formula with screen area and gain choice. Nice to be able to talk about these kinds of numbers for a change.

Art

Thanks, Art.

I guess I was kind of hoping for a target at which to shoot. 16 foot-lamberts just seems so passe!! I know much of this is personal preference, but at what point is it just too bright for movie viewing in a light controlled room?

With the 0.7 gain screen, with brand new bulb using low lamp mode and closed iris, I would be looking at around 36 footlamberts off the screen with my 16:9 screen size. (If indeed this is a completely accurate gain spec)

Kevin

The consensus appears to be more than 2000 lumens with a new lamp.

Just use the formula with screen area and gain choice. Nice to be able to talk about these kinds of numbers for a change.

Art


That is alot of lumens in a small, quiet package.. Whata break through..

Still trying to decide on screen material.

I was hoping to get an idea of the light output (foot-lamberts) that people were hoping / expecting to get off their screen, given the previously described Lumis output and their screen gains. (New bulb)

I will be getting a smallish 2.35:1 screen, 112" width. (85" 16:9 width)

I am leaning towards a Stewart graymatte with either .7 or .6 gain.

Thanks in advance for the info.

Kevin

Max power with that screen at 0.7 will give at least 38fL

Dim the bulb and its still over 28fL.

Thats at max zoom, so the actual number will depend on your distance.

The absolute worst, iris down and right on the min zoom is still 21-28fL.

CM, that's with new bulb, right? First time ever people will be wanting to buy other's used bulbs, and/or be ready for their own bulb to dim some. We can start a bulb club. When Jeff's is too dim for his 14' he can send it to someone wiht a 120". If we could just get Sim2 to seed the process :)

Any chance anyone noticed if the Lumis has discrete codes for the bulb dimming setting IR or RS232? If it does, one can have a setting for 2.35 and one for 1.78. Turn it up some when the light is spread out farther for equal ftL in both settings.

Speaking of RS232, anyone have it's command set yet?

CM, that's with new bulb, right? First time ever people will be wanting to buy other's used bulbs, and/or be ready for their own bulb to dim some. We can start a bulb club. When Jeff's is too dim for his 14' he can send it to someone wiht a 120". If we could just get Sim2 to seed the process :)

Yes, but using 2000lumen. All have been over that.

Wolfgangs was 1900lumen at 300-500hrs. That will have faded almost to max.

Mine was over 2000 with 150hrs on the clock. That will also have had a good deal of its fading behind it.

It seems that these units may have a similar fade performance to the HT5k.

I can see some poeple needing ND filters. I hope those that use them don't get a crap one, as they hurt the ANSI. Odyssey mentioned that Schneider do a top class one.

Any chance anyone noticed if the Lumis has discrete codes for the bulb dimming setting IR or RS232? If it does, one can have a setting for 2.35 and one for 1.78. Turn it up some when the light is spread out farther for equal ftL in both settings.

WOW,so simple and elegant its genius.

That could be a seriously cool thing to do. It wouldn't take long to work out how much offset was needed. I think the same number would be close to suitable for everyone as the fade is fairly linear.

Brilliant idea.

This is certainly a new and interesting problem. In order to maximize picture quality, i.e. avoiding a possibly detrimental ND filter, people are having to consider BIGGER screens than they were originally planning.

i know a guy who built an HT for a silicon valley billionaire in an SF penthouse. the room was NOT light controlled in any way shape or form.

WHat he did was setup a light sensor by the screen and set profiles to pull up so that he could change it based on time of day. he put in a light cannon, and then would ramp various settings depending on light and time of day. it was pretty sweet. lots of code, but it worked like a charm.

CM thanks. Seemed like an obvious tweak. Simple is good for me :D

Now I can have 50ftL in scope and 1.78 :eek: :cool:

Yesterday, our Az AV Club had a demo from a long time member who for years has had his own custom modded (he's a longtime video engineer)
NEC 10pg 9inch CRT. The member picked up cheap a used Faroudja DILA-1080pHD which he also demod. And the member is adding an addition onto his home for a forty foot wide curved Torus screen (to hopefully be done this year). He demod one of the two Christie S12 DLP projectors that he will be
putting in his new room which will do 3D, too. (Per the member: The S12 utilizes a 1.9kW Ushio Xenon short-arc illumination system for 12000 ANSI lumens. Based on 1.1” cinema dark 3-chip DLP™ technology, the S12 delivers vivid images with picture-perfect 10bit deep color reproduction. Built-in shutter, easy set-up with no convergence.)

Apparently Paul McCartney used 18 of these projectors in his last tour, and then after the tour they were up for sale - CHEAP!!! So the member picked up two of them. They are 2K units. The member has also picked up the theater lens, so when he wants to change from 2:35 to 1:85, pop in the lens.
I ain't no expert on this stuff but the member will be adding an iris and other mods to the projector.

Even with brightness down all the way, on the member's 10' wide screen,
the picture was amazing. Though of course parts were too bright. But once its setup with the 40 foot Torus should be amazing!!!@@

This club member doesn't like his name being used publicly, so lets just refer to him as "M". Alan Gouger knows "M" well and I'm sure Alan will keep his true identity on the "Q" as well.

Great but...

Please let's not start throwing the term TORUS around so loosely, the term is compound curved screen, a Torus has to be ray traced to the room.

Great but...

Please let's not start throwing the term TORUS around so loosely, the term is compound curved screen, a Torus has to be ray traced to the room.

When "M" said he's putting in a Torus screen that's exactly what he meant.
"M" maintains a low profile by not web posting but I assure you he knows everything you say, post and show here on AVS and elsewhere on the web. HA! I'm sure he's read and investigated all the stuff to do his digital cinema including 3D right!!!

This is certainly a new and interesting problem. In order to maximize picture quality, i.e. avoiding a possibly detrimental ND filter, people are having to consider BIGGER screens than they were originally planning.

I was originally planning on an 11 foot CIH screen. With the Lumis numbers I am seriously considering a 12 foot CIW screen firehawk. I have the room and have a line on a bargain for one of those. Also CIW sounds like it will be more 3D ready.

Can anyone point to gotchas in my thinking?

Thanks
Christy

I do CIW and I love it.

I was originally planning on an 11 foot CIH screen. With the Lumis numbers I am seriously considering a 12 foot CIW screen firehawk. I have the room and have a line on a bargain for one of those. Also CIW sounds like it will be more 3D ready.Sounds reasonable to me. I'm thinking along similar lines. I was considering a non AT setup, smaller screen. If I go larger and (uP) AT I get 2 hits on brightness, both being good for buring some extra ftL. The limiting factor becomes seating distance for my new theater. Still mulling that over... Can't speak to 3D, Peter's the fan there.

Very interesting. I would think that the other drawback of a traditional iris in the lens approach is a reduction in ANSI contrast because of an increase in backscatter as the iris aperture is reduced. DMD?

The reduction in ANSI contrast is probably not due to the backscatter from the blackened IRIS. I have not done a scatter analysis of the RS20 but I doubt it is coming from the IRIS at the stop position. What is probably happening is that there is a multiple scatter path that goes through the part of the stop that is not blocked as you decrease the IRIS . As you stop the system down you decrease the amount of light going to the image but do not reduce the scattered light thus you decrease the ANSI contrast.

The reduction in ANSI contrast is probably not due to the backscatter from the blackened IRIS. I have not done a scatter analysis of the RS20 but I doubt it is coming from the IRIS at the stop position. What is probably happening is that there is a multiple scatter path that goes through the part of the stop that is not blocked as you decrease the IRIS . As you stop the system down you decrease the amount of light going to the image but do not reduce the scattered light thus you decrease the ANSI contrast.

I'm sorry could you clarify this ? Mutiple scatter pathe by that not blocked ?

Art

Is there a review on the 3ds? Cant seem to find the right thread