Originally Posted by Fritz*
can you tell me the light loss in % of your system (filters and glasses) by using DLP /UHP based projectors?
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 ??