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  #1  
Old 15th February 2012, 01:46 AM
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Default short throw projector focal points

I need to purchase a short throw projector for a video mapping project.

I have noticed that most ST projectors beam upwards, allowing for floor placement.

Does anyone know if I were to tilt the projector for a placement that is directly centre of screen, will that mean that half the pixels will be out of focus?

Thanks.
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Old 15th February 2012, 08:29 AM
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you can't tilt the projector that much and expect to have a decent image.

redesign your installation or choose a different projector.
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Old 15th February 2012, 04:14 PM
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I think all the fix lens projectors have a screen offset, you'll need to get a projector with swappable lenses, lens shift and a wide available, lens shift to zero and it will fire straight out.
You can expect the projector to be larger then though...

BTW tilting a wide angle projector that doesn't fire straight results in major warping of the image for only a few degrees of tilt, you'll loose half your height with only 10degrees of tilt with some of them... Depth of field can be quite large however...
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Last edited by cat; 15th February 2012 at 04:18 PM.
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Old 16th February 2012, 05:48 AM
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Below are some of the specs of the piece. I cant use standard projectors as they are not completely covering the diamond and I don't think the project budget allows for projectors with interchangeable lenses. I am hoping to be able to do this with two budget short throw projectors.





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Old 16th February 2012, 08:46 AM
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that won't work. your trying to maintain focus over a huge distance (proportional to the overall throw distance)

The only possible way i could see to make this work would be to use 8 pico projectors, each projector doing one face of your diamond.
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Old 16th February 2012, 08:48 AM
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bit skeptical of it not working. I have sent standard throw projections over ten metres with very little differentiation in the focus..
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Old 16th February 2012, 09:10 AM
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depth of focus is proportional to total throw distance.

by all means try it out, but i'd be very surprised if you can make this install work with only 2 projectors.
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Old 16th February 2012, 07:58 PM
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Tom's right, the closer your projector is to the object, the less dept of focus you will get with the projector, and that object is pretty large, when you consider the distance the projectors are.

Can you make your enclosure larger?
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