Originally Posted by ellisr63
What projector are you using? It must be big bucks...
It is an OPTOMA. Sorry for the bad pic and the fact that I don't have the exact model number on hand but this thing is a native 1920 x 1080 with 5000 lumans! Can you say LIGHT CANNON? I don't think it cost that much but it does 2D at 72Hz and 3D (with DLP Link) at 144Hz.
The interesting thing was this projector did not have a lens fitted to it out of the box. There is a choice of long or short throw lenses available and they have to be fitted on installation. This system is using the short throw option (1.5:1~1.9:1). The long throw option runs from 1.9:1 to about 2.4:1 and costs about 3x as much as the short throw option.
Above is the projector mounted to one of my Projector Stations with one of my MK5 "Aussiemorphic" Lenses. This A-Lens is one of just two with the new (JVC safe) optic coatings. The other lens with these is my own (got myself an upgrade
) anamorphic lens.
When I first tested this projector, I was pretty impressed with the sharpness but thought the CR was going to be bad, but on that size screen, the image is pretty amazing and now I wish I had a screen that size in my own system.
TR is about 1.85:1 and the screen was custom curved to match the pincushion using the DIY ray tracing method first described by Vern Dias.
To measure pincushion, you need the following -
1. Projector with anamorphic lens
2. A flat wall to project onto
3. A tape measure
4. A straight stick that is tall enough to have the light shine on it when one end is on the floor - typically a broom stick will work here.
5. a roll of masking or similar tape
6. an assistant (optional)
1. With the anamorphic lens in the light path, project an image onto the wall.
2. Place the stick in the centre of the image.
3. Place some tape at the base of the light beam.
4. Move the stick to the edge of the image. The light should now be projecting below the tape.
5. Move the stick out from the wall (stay 90 degrees to the wall) until the light is just above the tape (like how it was when you first applied the tape).
6. Measure the distance from the stick back to the wall to find how far your screen ends need to come out to correct pincushion.
7. Repeat test for other end to ensure image is the same (just for the sake of being geeky).
And there you have "Ray Tracing" for measuring pincushion without the complex (and expensive) computer software.
Next up is connecting the 3 way active speakers. I will be using 3 MINI DSPs for both electronic crossovers and EQ. The 7.1 channel will use a total of 23 channels of amplification.