Originally Posted by coderguy
Yes, the ideal position is to match the position of the PJ (center of lens) to the center of the screen (both vertical and horizontal center). Ideal is however usually not realistic.
In situations that require a conditional decision, it is better to test the projector at the mounting spot before permanently mounting it.
You can use fishing string to see where the image goes, tack or tape a piece of string to the wall where the bottom of the screen will be, take the string and tighten it and pull it towards the center of where you think the pJ LENS should go. The fishing string now represents the bottom of the projected image (you can tell if it will be in your way). You can also measure it using an online graphing calculator or you can eye it, just draw an imaginary line from the lens to the bottom of the screen in your mind.
Another method is to simply temp-mount the projector. You have to be careful though, a tall shelf or a ladder is one way to test it, tie it to the ladder with a rope or bungy cord for safety so it does not fall.
Thanks, coderguy. I will try that string trick.
I will have an adjustable shelf in my PJ cabinet, so I can just test different heights, although I think I should just be able to do the same thing by tying the string to a vertical post that I put temporarily in my PJ cabinet to simulate where lens might be.
I should just then be able to slide the string up and down the post to mimic different potential vertical lens positions and then just try to match that position as closely as possible when I put the shelf and PJ in place.
I guess if I ran strings from the lens position to both the top and bottom of the screen I could also easily see the diameter and position of the circle of projected light at the entrance to the PJ cabinet opening (I guess I could do some math, but this seems a lot easier).
I would be interested in this for potentially blocking out most of the opening with something (maybe a dark piece of MDF or even poster board) and just cut a round opening just big enough for the light to shine through.
I'm thinking of doing this to help minimize the size of the opening through which dust can enter into the PJ cavity (and possibly to give the HT a more sleek appearance).
Does anybody who have their PJ's in a cabinet vs. ceiling mounted do this (cover the front of the cabinet with only a cut out for the light coming through)?
I currently have the opening framed to be 2' H x 1.5' W, but may reduce the W when I trim out the opening with casing as I think I will be more interested in having vertical vs. horizontal flexibility. It's not a huge opening, but still, since the RS45 no longer has the dust cover, IIRC, I'm wondering if this would be worth it.