animated snow globe from pico projector?

[jintonic4]

I want to build this: http://makezine.com/2011/09/19/pico-projector-light-fixture-free-code-desktop-spherical-display/

 

https://www.youtube.com/watch?v=vWkfJdNhpv0

 

I tried contacting the author for help, but no response. Not surprising, since its been few years.

 

1) First problem is, they fisheye lens the dude linked to is out of stock. http://opteka.com/magfisheyelarge-1.aspx

What a bummer, was very affordable. What can I use as replacement? My lens knowledge is pretty bad.

 

2) Second question/problem, the projector, I have a Aaxa ST200 150 lumen pico projector. It's a decent little PJ with short throw lens but I haven't been using it for a while, and don't mind using it for this. If a laser projector should really be used instead, I'd like to know what options are good if anyone knows. I searched but all I found were 10 lumen projectors. I don't see why laser would be needed as its blurry anyway.

 

3) Third question is what to use for the diffuser globe? I got my own toilet light globe fixture off the wall to try it out and honestly it looked terrible, I don't know maybe mine was more thick than this guy's, but it made everything a bit too blurry/dim to be fun even in complete darkness (and my PJ has 15 times more lumens...). I didn't expect anything perfect but it was a bit too bad compared to his results.

Camera made it look brighter but you can see how blurry everything is

http://I.imgur.com/H2Ozrms.jpg

[musht]

Fisheye lenses don`t appear to be rare, guess its matching something with the aperture on the projector, hence phone fisheye on pico projector.

 

Light source in the projector ain`t going to be the critical factor wouldn`t think, laser video rather than laser beam vector projection guessing you mean.

 

Your globe is meant as a diffuser, not going to get a sharp image through it, need something thinner.

 

Look up Pufferfish displays and this has a lot of background

 

http://paulbourke.net/dome/

[jintonic4]

No, I'm not talking about laser vector projection. The guy in his article says that the advantage of a video projector with lasers as light source instead of LED is allowing to have a projection which doesn't need focusing, even though for such small distance he says maybe it doesn't matter. I don't know why that's the case myself, maybe less light scattering from coherent light source such as laser? I will email him btw, thanks!

 

I see a lot of fisheye lenses out there, I just don't know how to calculate which I need.

 

BTW, what about sand blasting just the inside part of a transparent light globe to make it a diffuser, but a thin one?

[musht]

Laser raster Vs vector was phrase was grasping for. Raster will have infinite focus in theory but not a big advantage to this wouldn`t think.

 

Lenses outside my understanding.But looking at the orginal project, it aint that sharp at all.

 

This one uses 8 blended pico projectors on a slightly larger sphere:

 

http://spectrum.ieee.org/tech-talk/consumer-electronics/audiovideo/spheree-display-3d-interactive-animations

 

Sand blasting is never that even, acid etching can be but hydrofluric acid is not diy friendly, rear projection material thats thin, inflatable?

 

Interesting project, please remember to update what you find :-)

[jintonic4]

Lenses outside my understanding.But looking at the orginal project, it aint that sharp at all.

I dont think its because of wrong or bad lenses, just the limited number of pixels for a 8 inch sphere. Or perhaps he also used a thick glass which is diffuse all the way through, which makes things too blurry.

 

Sand blasting is never that even, acid etching can be but hydrofluric acid is not diy friendly, rear projection material thats thin, inflatable?

Don't know anything like the last one. Maybe some kind of paint if sandblasting wont work well for this?

[musht]

 

I dont think its because of wrong or bad lenses, just the limited number of pixels for a 8 inch sphere. Or perhaps he also used a thick glass which is diffuse all the way through, which makes things too blurry.

 

Think thats the exact issue , resolution, looking at Pufferfish`s units they use a whacking great Barco for a not very big sphere.

 

Acid etched glass looks great and was traditionally how lamps were frosted, hydrofluoric acid has 2 interesting properties it etches glass but dosen`t burn skin, it soaks through the skin and decalcifies bone. Nice even ground glass effect though.

 

Paints only work as front projection material, for rear projection needs to be a property of the material itself, not sure how to create a thin sphere of it though. Beginning to see why most domed and spherical projections are front projected.