Well, I promised give a short review on my new OMEGA 3D projector system. I turned out to be a DIY lesson, but maybe it's interesting for some freaks like me.
- Geobox 201
- 2x Benq W1070 (1920x1080 DLP, 2000 lumens, 10%(of image height) vertical lensshift, 1,15-1,5 throw)
- Omega DLP small 3D kit
Firt of all I tried to place the filters in front of the lenses, but the filters only work fine with a throw larger than 1.5. So i just abdicated the projectors warranty and placed the filters inside the projectors. The result is a performance, which is slightly better than for the 1.5 throw and filters in front of the lens, but within the entire zoom range. Sounds easy, but, well, let's see.
first of all i opened the projector:
First try: place the filtes directly behind the lamp -> negative result, as the light is highly focussed onto the DLP roation wheel (area approx. 1,5cm square), and the numerical apertur (the angular spread) is to large, so you get a lot of partial color shift and lots of crosstalk - a pity, it could have been so easy...
Seconf try: Only way to get inside the 'optics', demount the zoom lens. The next image shows the DLP-optics box from the front (omega filter inside are already inside, but not yet within the light path).
To get a better overview of how the optics inside work:
And the red box is where I placed my filters. How did I do this?
For some reason (maybe maintainance & repair) there is a little hole/slot in the top, covered by a small plate:
And as I wanted to watch movies in 2D using only one projector the challenge was to remove the filter occasionally. So i 'designed' a aluminium block, cut out 16x16mm pieces out ot the filters and mountet them to some wire using epoxy (i know, pretty much quick & dirty, but it works):
I placed the alu box inside the slot (from the top), bend the wire monted at the filters by 90degree to fit in a little hole inside the box, so i could fasten teh filters from the top using a standard screw. DONE.
now there's the filter in front of the lens that collimates the outer light (coming from the ratation wheel) into the chamber with al the other optics:
And the good thing, I can easy remove the filters by pulling the alu block from the top though the top slot (the filter won't fit through the top slot but the lift is just enough to clear the lens).
I realized the lift from outside the projector by another wire i can easily push or pull (and up to know fasten it by duct tape occasionally ;-) ).
OK the performance:
Virtually NO crosstalk. The lamp has not a pretty FULL color spectrum, so you get some color error. The Benq W1070 has a fine tuning Hue/Gain/Offset adjustment for 6 colors (RGB & CMY). you can compensate most of the color error, but thanks to mother nature and our own built in white balance, the rest is done by your own eyes (this assumes that you dont have other white light in your flat). I only see a noticable luminance difference at really deep red and cyan tones, but you won't notice in a movie, and it's a litlle drawback I can live with respect to the rest of the performance.
I have the geobox 201, so alignment has to be done manually. Even with lens shift (which is just enough with the BENQ W1070) image alignment is a nightmare, but once you got it, you really have FULL HD, no Flicker or crosstalk and a really great picture. In my opinion, it's much better and brighter than the commercial cinemas. I'm enjoying it a lot.
I've got a general recommendation for this DIY two projector system. The depth in recently published 3D BDs is much more professional in terms of far field points. So you newer get problems on large screen, however, in older IMAX 3D movies sometimes the far-field disparity is so huge on a large screen, that the eyes have to diverge and the 3D effect is decomposed or really uncofortable. Since the geobox 201 is not able to do a hotizontal alignment (adjustment of depth) I recommend a very good bluray player: Panasonic DMP-BDT234EG. It's able to adjust the depth (shift the 3D image towards you) so that this problem is minimized. It also plays 3D MPO files and AVCHD 3D, so it's a good investment, especially for people who produce their own 3D content.Edited by philiwahnilli - 6/4/13 at 10:21am