garageCube

[2lifetalent]

Anyone try using this type of projector for mapping? It seems these projectors could be extremely useful for indoor surfaces with a lot of traffic.

http://www.epson.com/cgi-bin/Store/jsp/ ... V11H602020




The question then becomes about how to best accomplish an accurate spatial scan. If the projector is setup as shown (on the same wall it is outputting), does the camera need to be an ultra-wide-lens setup from that same angle, or can the camera be setup facing the output (normal lens, from the front perspective). I know that slightly off-setting the camera from the projector will still create an accurate spatial scan, but to this degree?

Cheers.

[sigmasix]

you don't need the same lens on the camera and the projector.
But I wouldn't recommend such projector for video mapping. The fact the it's ultra short throw make it very sensitive with positioning. You rotate the projector 0.001° and the image moves lige 10cm (I exaggerate a bit but you understand what I mean).
So you would need a very strong way to fix the projector so nothing moves and the image is still mapped on your objects after a few days.

Also, a lot of non professionals projectors are moving by themselves with temperature changes… Your image won't have the same position if the projector is hot or cold. So if it's for a one shot event it's fine but if you plan to havec a 1 month installation you can be sure that by the end, everything is not mapped anymore.

By the way, for such long time installations, you must be very careful with the use of wood as wood works and moves and for videomapping it's a real problem (remember, 1/5mm projection move and a lot more of the image moves depending on the focal length and projector's distance)

[2lifetalent]

Thanks for responding. This is very helpful.

I was going to use this projector for a permanent install in a venue. It would be installed into cement. Do you think that would be ok? Otherwise, do you have any suggestions for a more professional projector and/or a means of keeping a permanent installed projector completely aligned?

A short throw projector (as opposed to an ultra short throw) projector is also an option, just a slightly more challenging install. Do you forsee the same problems with a regular short throw projector install?

[sigmasix]

the heat deformation is a problem for all projectors, some are really ok with it and some are problematic… I would recommend to do some tests where you place your projector on the floor and put some marks on the wall where the image is. Then you check a few hours later how it is.

If the projector is screwed to cement or concrete it shouldn't move then, but take into consideration the heat it produces