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Ocular
11th April 2002, 02:25 PM
I am trying to find a way to make my throw distance shorter and my image larger for rear projection. I am using mirrors at the moment, but they take too long to set up. I have heard of mirror boxes? but have not been able to find any info on them. ANY suggestions???

sleepytom
11th April 2002, 03:22 PM
depending on you projector you may be able to get a wide angle lens - they are not cheap but do the job far better than any mirror solution.

or you could build a bigish box that housed the projector and the mirrors so that its all alinged properly - which would save you time setting up but would mean that you have to cart a big box around with you....

MoRpH
12th April 2002, 05:01 AM
Get a bigger projector :p

Sorry I know that wasn't really help full but I had to say it.....

Personally on the few occations I have had to do it I have mirrors the only real solution (short of what tom said) oh well....

vjpixylight
13th April 2002, 05:13 AM
Like tom says it needs to be done properly with a Wide angle lens, and yes they are expensive, 3000.USD for a wide angle for my sony...Amazing what certain lens can do though...

MoRpH
13th April 2002, 05:16 AM
Maybe its possible to get your own lens ground and fitted???

DocSavage
13th April 2002, 05:52 AM
I'd love to hear some details as to how the whole mirror thing works.

MoRpH
13th April 2002, 06:12 AM
Well its hard to explain without diagrams but basically your compressing the throw distance of the projector to get to a certain size output by using mirrors to bounce the signal around in a smaller area than what would be needed to reach that size...

DocSavage
13th April 2002, 07:07 AM
Now it would be cool to have someone write an article on THAT! :alien:

MoRpH
13th April 2002, 08:23 PM
Its actually an incredibly simple principal really (just hard to explain without a diagram), but the projector beam travels the same distance as it would normally to get to the required size but it just uses a mirror or 2 to bounce the beam @ right angles to make it travel the required distance...... check the eye candu archives as I'm sure there was a thread on there about it ages ago....

sunep
14th April 2002, 12:18 PM
Well in this discussion as well as the discussion on the eyecandy list, the seem to be some confusion regarding this subject.

I bought the book Videowalls by Robert S. Simpson. This book covers the most concerning projectors and anything else that make a large electronic image. I can only recomend it.

the isbn is: 0240 51505 6

I got from www.amazon.co.uk
use this link: http://www.amazon.co.uk/exec/obidos/ASIN/0240515056/qid=1018786418/sr=1-2/ref=sr_1_0_2/026-6176753-3503650

Sune

vjmedia
17th April 2002, 06:21 AM
We have built a rear projection system however, beware of the double image you get with standard mirrors. ie the light refleting off the glass, then the aluminium mirror material in the back. Over a larger distance, it might be neglegent. The correct mirror is a front surface mirror. they are around $500m2. Our RP system is only 900mm deep. Melb AU. Hope that helps

MoRpH
17th April 2002, 06:39 AM
Hey kent, nice to see you on here...... floggin your wares as usual :p

BTW mate check out the SVi forum :)