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Turning the Hayden Planetarium Into a Giant Videogame
pigrabbitbear writes "Remember your first visit to the planetarium? Neil DeGrasse Tyson does — it was what inspired him to become an astrophysicist in the first place. That same planetarium, now under Tyson's direction, is currently undergoing a transformation the likes of which Neil's young self couldn't have possibly imagined: It's becoming a giant videogame."
No! We must never forget that he was the man who demoted Pluto. I liked Pluto.
The year is A.D. MDXLV...
Johann Albrecht Widmannstetter: Dude, Nicolaus Copernicus was awesome.
Bartolomeo Spina: No! We must never forget that he was the man who demoted the Earth as the center of the Universe. I liked Earth as the center of the Universe!
Ezekiel 23:20
Awesome? There is a movement to get Neil DeGrasse Tyson downgraded from Astronomer to Dwarf Astronomer.
I'm an American. I love this country and the freedoms that we used to have.
While the clockwork versions may still exist in small school planetariums, the digital-mechanical hybrids are all long gone. You can thank Evans and Sutherland for demoing a version back in the early 80's, using a single, b&w tube projector through a Nikon 8mm (fisheye) camera lens. In spite of limitations that you'd all laugh at, it was instantly obvious that this was the future.
MichaelSmith is correct, the digital video projectors have yet to get close to the pinpoint-sharpness of the old electro-mechanical projectors, and those monsters were a delight to watch in motion. But having operated those old beasts (Spitz STS), the limitations far outweigh the benefits.
With the near-perfect rendition of consistent motion across the entire field of view, a modern digital video planetarium can utterly swamp the viewer's visual cortex: "sharpness" just doesn't matter when you can fly through Saturn's rings. I can say that I can't discern the "blurry dots" once the show gets rolling, I'm pretty comfy asserting that the average viewer's just drooling while their brains leak out of their ears. Having endorsed the modern, I'll confess to a desire to sit and watch the last STS (at Eastern Kentucky University) just quietly "roll" the sky, but that's nostalgia talkin'.
As for playing a game on a digital video dome? Innnnnteresting. I'm happy to tell you that as a witness to the history MichaelSmith elevates, get outta my way, I'm goin' to Dr. Tyson's place for game-night.
There are 2 ways that modern projector based planetariums work. The easy way is with one projector and a fish eye lens. The lenses tend to run about 100k and the single projector will have to be very bright because of how spread out it will be. The hard (but arguably better) way is by mapping multiple projectors together. This will allow for a much brighter image because the brightest projectors available today are about 40k lumens. 8 20k projectors are obviously much brighter.
It takes quite a bit of work to map a dome like this. I spent close to 48 hours straight mapping a 90' dome for a party for Putin and I am considered very fast in the industry. Basically you project a grid and twist the points till the line up correctly allowing for about 20% overlap of the projections. You can use a modeler like Gmax or custom warping programs that most professional media servers have these days... We use Coolux - Pandoras Box.
Ideally all the warping was already done for these guys and all they had to do was plug their system into a live input card (capture card) and route their systems through the media servers at the planetarium. More likely they had to re-map it. They did an ok job, but you can definitely see distortion as the image moves between projectors. The bigger problem they are having is with sync. This is always a really difficult issue between multiple systems and one of the main reasons to use a quality media server. You can clearly see the computers are wildly out of sync at the end of the video. Even 1-2 frames of sync loss will be clearly evident in a projector blend.
Either way, the project is really cool. If anyone is interested there is a free open source media server out there capable of mapping domes and other 3d objects called vvvv (although it is a bitch compared to the commercial solutions). Pure Data is also worth looking at. It is an open source alternative to Max Msp which does related interactive video things.