> > > I am think of a open of about 12cm or up to 26 cmSo you *were* talking about the small scale. You'll get a different effect with such a small sphere, but it could surely work. Because the radius of the sphere is a lot smaller, the position in which the perspective 'works' is going to be a lot tighter.
> > > so its portable
> > Either you're missing a 0 there, or we're talking *really* small.
> > At the *really* small scale, I wonder if you would need the
> > dome-mirror to project on; you could probably just use
> > rear-projection on the dome.
> so do really need the dome to large enough to stand in?
> I was think of something head size
On the other hand you get an attractive effect when walking past the installation, as the perspective changes with your movement. I have used this effect (on cylindrical surfaces) to attract spectators to the display-window of a gallery with great success.
You will probably need a projector that emits more light than the Aiptek (ie: 2000 ANSI Lumen or more, especially if the room you're putting your installation in is not completely black). Like I said focus and depth of field might be an issue on a small 'screen', but I have had reasonable success with putting 'closeup'-type screwin filters in front of a projector (eg 1, 2 or 4 diopter). (Note that most projectors don't have filterthreads, you would have to be creative about that).
Something that is going to annoy you about projectors is that most of them (the affordable ones anyway) don't project straight ahead, but slightly upwards instead (there's basically a shift lens in there). That is going to make the image you want to project from the rear a bit different from a simple 'fisheye'-like image. It may even look better just projecting a rectilinear image, even if that is not quite correct.
For a rear projection surface, you could experiment with a cast made from a cheap-ish frying wok. Get a real asian one, without a flat bottom. Grease it with some nice clear oil on the outside so it does not 'stick' and see if you can poor an even layer of latex onto it. If that comes off easily, try another one and reenforce that one with an additional layer of liquid epoxy (after the latex has dried). It might just work. Or it could be a catastrophic failure ;-). I did not test any of this... Experiment!
>Mini-dome "personal" theatres are a nice idea. It is a middle ground between domes and some kinds of HMDs. Luc Courchese uses a sort of wearable doughnut projection concept for some of his panoramic video pieces. See "Living by Numbers"
> > > > I am think of a open of about 12cm or up to 26 cm
> > > > so its portable
> > >
> > > Either you're missing a 0 there, or we're talking *really* small.