On 9/7/05, Stef Mientki <s.mientki@mailbox.kun.nl> wrote:
> Yes you're right.
> I just did some tests with medium bright LEDs at 100 mA (goal is bright
> LEDs at 200 mA),
> and 5Hz is too low, 20 Hz seems to be a good compromise.
> So the 1 degree equivalence is 125 usec.
> Even with this "low" current and medium bright LEDs, 10us pulses (for
> the weakest stars) seems to be just bright enough.

Have you considered a laser scanner assembly pointing into a fisheye
lens?  You can cover the entire dome with a few lasers, some optics,
and a fast scanner.  Would probably be less work, and perhaps cheaper,
than a spinning assembly of hundreds of LEDs.  Much less noise as
well.  Take off the translucent dome and the stars appear on the
ceiling.

-Adam

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