| Author | Message | ||
     Peter Swanston (Peter64) New member Username: Peter64 Post Number: 1 Registered: 2-2007 Rating: N/A |
I am attempting to setup a dual projector configuration but am rapidly finding that the PD6240 and other projectors are hard to come by as they are no longer in production. I think what would be really useful at this stage in the game is an updated list of projectors that work. I have read a number of reviews and looked at a variety of sites. http://www.razor3d.de/positivliste.asp I have done a lot of hunting and seen a variety of things. Regarding why a given projector may not work some of this information seems to be somewhat conflicting. 1. The color wheel I know that I want a projector that can produce 85hz not just 60hz for this reason I know the color wheel is going to get chopped up in a strange way. It would appear all BenQ projectors use a 5 segment color wheel which does not have equal proportions. So how does this effect anything I did not know so I had to research how single chip DLP works. http://www.tvauthority.com/dlp/dlp_tv.asp?dept=42 Anyways at the end of the day I'm left knowing that no matter what projector I buy the color wheel has not been designed to be rotated once for every cycle at 85hz so the colors may not look right. I would be more than happy to test this at a store but unfortunately most stores in Canada do not have the equipment or facilities to allow me to test frame sequential stereo 3d to see if the color wheel looks good. Even if I know that the DLP chip used is the same as other models and the color wheel is identical it does give me some vote of confidence but I've been reading about a variety of other errors that crop up. 2. Synchronization Many people appear to be complaining that there projector will go in and out of synchronization every few seconds I have no idea what might cause this all I can think of is that according to the specs on projector manufacturer sites the refresh rate is never exactly 85 hz for example on the BenQ MP720p which i most recently considered in the manual it says the refresh at 1024 x 768 is exactly 84.997. http://static.tigerdirect.ca/pdf/BenQ_MP620_720_720P_User_Guide.pdf (page 58 of 61) I guess I'm really looking for two things, a sort of heuristic I can apply to a projector to determine if the color wheel when not divided perfectly using frame sequential 3d and shutter glasses will look ok. And how to determine if a given projector will result in synchronization issues making it completely useless for active 3d. Secondly from someone who has a working configuration with a projector that is still in production and preferably not too expensive what projector do you use. I am actively considering the MP720p as the price lumen and quality ratio seems to be good but I would be interested in any input the scene has. Thanks again and sorry for any negative tone I may have I've just been dealing with two companies who claimed to have the PD6240 only to tell me they are out of stock. | ||
| Alan Johnson (Ajay501) New member Username: Ajay501 Post Number: 9 Registered: 4-2006  Rating: N/A |
Hello Peter, I use both an Optoma EP-739 and a Sharp XR-10X at 1024 X 768 (and together for a 2048 X 769 display) at 85HZ and 75HZ. I have not experienced any of the sync problem you described with the projectors. Also, there is no noticeable color distortion. There might be a slight color change in one eye, but I have to look very carefully with one eye and the next to detect that it is there. I don't know the specs of the color wheels on these projectors, but I'm very happy with the 3D they produce,  , at least for gaming. With 3D-DVD movies it's hard to say ... the quality of the 60 Hz low resolution graphics is a bit disappointing ... but not because of projector limitations. | ||
| Peter Žiak (Hornet) Intermediate Member Username: Hornet Post Number: 66 Registered: 4-2006 Rating: N/A |
Hi MP 720p Benq is problemless used for 3D pageflipping stereo at 85 hz (I personally before change it to 6240 (this was second projector, first was 6240), and one from my friends 9months) this is modernised 6240 with better lamp, smaller DLP chip, the same resolution as 6240, the same refresh. the price is good, is still, and the heat air is ejected to front,Only one disadvantage is cca 10-15% smaller picture from the same distance. With 6240 I have 400 hours , all in stereo!_ | ||
| Peter Žiak (Hornet) Intermediate Member Username: Hornet Post Number: 67 Registered: 4-2006 Rating: N/A |
I use 6240 becose I use dual projectors (2048x768) 85 Hz 3D active stereo setup for my soaring simulator, the second my projector i will too 6240 -the same picture diameter, (have changed new 720p to 100 hours old 6240). 720p is good, the lamp time is longer 3/4k hours to 6240 2/3k hours. | ||
| Peter Swanston (Peter64) New member Username: Peter64 Post Number: 2 Registered: 2-2007 Rating: N/A |
Thanks guys your advice was really great. I think it would be really good to setup a wiki of some sort with projectors that work and to what degree they work. I remember someone had said they were going to do this but perhaps when I buy my equipment I will setup a wiki with a giant table on wikipedia and we can all add our projectors and how well they work! | ||
| Andrew Woods (Andrew_woods) New member Username: Andrew_woods Post Number: 6 Registered: 4-2006 Rating: N/A |
I presented a detailed technical paper on this topic at the 2007 Stereoscopic Displays and Applications conference last month. www.stereoscopic.org/2007 The paper describes a survey of 45 consumer DLP projectors to establish whether they were compatible with time-sequential 3D - in various video modes and connection methods. The paper also discusses the reasons that some projectors are not time-sequential 3D compatible e.g. deinterlacing problems, synchronisation problems, etc. The paper contains a compatibility listing for the 45 DLP projectors tested - including listing 15 projectors that were 85Hz time-sequential 3D compatible. The full reference for the paper is: Woods, A.J., Rourke, T., (2007) "The compatibility of consumer DLP projectors with time-sequential stereoscopic 3D visualisation", presented at Stereoscopic Displays and Applications XVIII, published in Stereoscopic Displays and Virtual Reality Systems XIV, Proceedings of SPIE Vol. 6490, San Jose, California, 29-31 January 2007. The full paper is available for download here: www.cmst.curtin.edu.au/publicat/2007-05.pdf |
