heya,

does anybody knows how big you can let the acrylic be so that you can still get the IR light in the middle of it.
Even if you use a lot of leds is there a maximum width to it without loosing the blobs?
cheers
i’m supposed to build a big one for a project

Well it’s kind of limited by the thickness and overall stock dimensions of the acrylic on an FTIR setup. If you used 1/2” thick acrylic I think you could go up to 4’ x 5’. Acrylic comes in 4’ x 8’ sheets unless special ordered.

For large designs I’d go for a DI setup, especially if its as big as 4’x8’ ... it’ll be a lot easier to make and more stable. Also i read on the forums here on a someones blog that you arent able to maintain the FTIR effect if the screen becoms to large… i dont think 4’x8 would cause this problem.... but the easiest method would be a DI setup.

Taha

thanks for the quick replies guys

@Taha - about the DI i hear it is a bit tricky with the IR lamps, it is hard to set them up to have an even spread on the screen so i’ll try FTIR

i’m probably going to stick with 121 cm X 161 cm (4:3). if i’ll install leds on all sides and use an aluminum frame to reflect back whatever comes out, hope it will work.

as for the thickness, the thicker the better ?

For that size FTIR is a good option… if you making a table setup then i’d go with 1/2” ~ 3/4” thick if you plan to do a wall setup then you could even go with 3/8” thick but from my experience 1/2” thickness should be kept as the minimum.

You could go thicker it shouldn’t make a difference i think, to how your setup behaves, the only thing thats going to happen is that your acrylic sheet is going to get very heavy…

Taha

cheers guys
will come back with updates