Official Omega 3D passive projection system thread - Page 6

i do not have any 3d-xl's tp test but from what i understand you need to switch one of the boxes to match the others L/R selection to see 2d, but the image may not look good if the two projectors are even slightly missaligned. the geobx has a switch on the box and the remote to switch between 2d and 3d and with the alignment tool built in you will get great aligment to where 2d looks good with both projectors on. see some of the photos i posted in this thread a little ways back on this exact issue.
if your going with a curved screen you will get the most of it with an alignment system. i do not have any reccomendations for a silver screen as i dont use them, our 3d filter system dose not need a silver screen to funtion and you get hot spotting with the silver coating.

i think your in a similar situation to most with a home theater where you will be watching 2D most of the time. any high gain silver screen will not provide as good of a 2D image as a matt white non silver screen curved or not.
1) do you have to buy a screen a screen now? and another projector ?
2) i would not go with silver high gain unless you plan on using polarizing
3) the geobox dose not control the projector power but can select 2d or 3d from the remote and with the alignment ability 2d looks great with filters in place
4) you can leave any 3d filter set in place if running both together for 2d or have a flip mount and run one projector with its filter moved out . it all depends on what is easiest for your mounting.

personally i reccomend my own 3d system so you dont need a silver screen but polarizers are fine for a lot of peoples choice. its really dependant on what projector you really want and what you want to get out of it.

G-201 Quick User Manual-draft.pdf 484k .pdf file

the lenses in the omega glasses are not really that small. they provide a good field of view. one dose not "see" 3d in your periferal vision only in the center of your eye. even without glasses you would have to move your eyes around or even head to see all of an image that size from as close as you are to the screen. from calculation ive made of my glasses if you have an average inter ocular distance between your eyes of 65mm the outer field of view is 80 deg so from 165" away you should be able to theoretically see 260 " wide image. if your interocular is smaller say 63mm apart and you take into account obstruction from the nose bridge you still have a fov of 67 deg making for a 200+" image at 165" distance...
with all that i have to say the projection filters will not work well on ultra short throw projectors, so as long as your throw ratio is 1.5:1 min or best closer to 2:1 you will get good performance.. that is not connected to the viewing distance.

yes at least for a dielectric filter system like ours it is best at a 2:1 throw but will work fine at the 1.6:1 throw. its just the 1:1 and shorter throw projectors give rise to issues with a system like this.

$700 for the 201. not bad considering 2 3d-xls, a splitter and cables will run you almost 600. i will have a few in another week.

i agree that the omega filters will function better with throw ratios over 1.8:1 but the color change toward the corners you mention are somewhat dependant on the projector output spectrum as well as filter / angle functions. i do not see but only the faintest color variation at 1.5:1 throw on my hd20's. now its a different story with a pair of LCD's i had where i could see more of an issue complicated by the shorter throw as well as the spectral profile of the projector.

the usable area of the small filter is 55mmx 35mm and the boarder is aluminum with 3mm holes on two sides. i dont have the dimmentions for the overall with the mount here but i will post it. bjomega is the owner of the company and its his ebay account. they are also listed on amazon and another ebay listing. all the same product. you can specify DLP or LCD projection filters when you order.

this was covered extensively in the ultame passive 3d thread. its best to understand 3d in general and compare efficiency relative to other 3d systems. in cinema testing durring development of this 3d system the calibrated dci numbers are as follows, ReaD Z = 15% efficent, Dolby 3d = 12% efficient, Xpand = 17%, RealD XL = 28%, omega 3D / Panavision 3d= 18-20%.

now that was all a former version of of my filters and since the version we have is a little better but it all is dependant on the actual spectrum from a given projector and the state of calibration. LCD projectors have far less spectral range due to deep filter notches in cyan and yellow as well as a blue / violet blocking filter to protect the LCD/LCoS matrix. DLP dose not have the deep cuts in spectrum in most small DLP units.

UHP ( mercury ) lamps have poor color rendering due to spikes in output in green and they lack red performance. every maker has their own method of filtering in the color wheels that vary the kind of performance one gets with a spectral filtering method like ours. for the most part conferance room projectors have the most spectral range and the least spectral filtering and hence are more efficient with this method, but the color is not as good as a home theater DLP.
my last tests of a DLP/UHP home theater projector using optoma HD20's shows far better than 25% efficiency . infitec claims they are better than the older dolby version of their chomatic filter tech but its a lot of hype. people get too cought up in numbers

the method and equipment needed to actually test this is very specific as one needs to make measurements thru the glasses of energy reflected from a screen being innuminated by the filtered light. the measurment device needs to have spectral resolution of 1nm or so to make any accurate measure of whats going on. ive built my own device for doing this as well as spent a few years refining the system and the tools needed to quantify performance.

one important thign to keep in mind is the % efficiency is not a good measure by itself of a 3d system . its also the level of extiction of the other eye's energy. it dose one no good to have a high throughput if there is crosstalk / ghosting. we get 1000:1 s/n on center while getting out % efficency, polarizing mostly retains ~80:1 at best and 45-50:1 in a lot of setups. the dolby i get to test in LA had ten times the ghosting of our system while getting less % light and terrible color balance without the color correction server setup just right.

dose that help ??

no one can buy infitec projection filters but people involved in cinema instalations. the glasses on the other hand i have seen and they have poor extiction, at least the ones with the coatings on mylar. you sound connected to infitec. the projector filters in the new 3-4 design are different enough from their glasses like the older dolby system that one cannot evaluate the system without having the entire system and the color correction server. i wouldnt refer to it as exellent, maybe decent.
from the way they split the spectrum it wold not function well for color balance between eyes in a uhp lamp based system without digital color correction. if you are part of them and want to talk further private message me.
Cheers

i agree, we looked at making a wheel for in front of a small projector but its costly when you include the control and mounts. cinema already uses these wheels in fact the wheels in the picture are cinema products, one is a 96mm wheel for barco and christie projectors and the other is i believe a 122mm wheel for older 2k systems. we make these as well with our tech in them and beat Dolby at extiction, efficiency and no need for the color gamut correction server rack system.

this also brings up a question, if the image is switching for a wheel with the 40% dark time for image change and all is it not an active system ? the flicker is created in the projector and not the glasses but its the same thing isnt it ? true passive 3D must be done with two projectors.

im glad you found this thread. it will give you the best 3D you have seen. the Optoma HD20 is one of the best projectors for our 3D filter sysem i have tested to date for home theater. you can see some images i posted here that i took using these hd20's and the filters on a 14' screen.
i do not need lens shift as i can place the projectors where i need them to be. the rack i made has adjustment to one shelf to tilt the top projector a little to get the images close enough for 3d. as one eye dose not see the others image the small missalignments are not seen. the images i posted though were perfectly aligned using the geobox G-501 demultiplexer and its image warp/alignment tools to get the two images so well aligned that 2D with both units on and filters left in place looks great. i can just switch between 2d and 3d with a remote. the box takes hdmi in and automatically splits a 3d image to the two projectors.

the other method is to use an htpc and a good dual output video card and the stereoscopic player to demultiplex the 3d,

any other questions i can help with just ask.