Planetarium Star Projectors

[Jem]

I'd love to see a couple of photo's of the inside of the Omniscan. Particularly the effects wheels...

[SpitzSTP]

I'd love to see a couple of photo's of the inside of the Omniscan. Particularly the effects wheels...

I have some pics of the sphere opened up, about 8 posts back. The effects wheels are barely visible and rather hard to see because they are literally packed into a very tight space. Getting in there with a flashlight, there are are two discs each loaded with 5 smaller wheels. A few of the locations are empty, but most are populated. The two wheels are driven by rubber-tooth belts mated to what I think are DC servo motors or stepper motors. I'll try to get the camera in there which is harder to do now that the sphere is up on a pole. I have a hunch that the effect wheels mechanism is not much different than what Laserium has used, and numerous other of projector builders, just packed into a smaller space. The components inside are precision-machined and mounted in bearings.

[SpitzSTP]

I am told, that this Omniscan is the "sister" of the one from Kansas City, both manufactured at about the same time but in a completely different configuration for a different customer. The housing is about the size of an upright fridge and the lens is around a foot to 1.5 foot in diameter. It is interesting that the ion tube is mounted at an angle and there is no use of fiber optics (no need, I suppose). I wonder if the card cage contains the same driver cards as this one, I speculate that it does. This one came out of a planetarium that was being dismantled, and I wonder exactly how many other Omniscans exist in service -- I can only find two or three by searching the .net.

A friend of mine owns another Omniscan, hopefully he won't mind if I share the pictures of his system here.

[swamidog]

one of the primary differences between the omniscan and the laserium rigs i've seen is the laserium projectors can have multiple scan heads. this leads to some really cool effects because you can do things like have one head projecting through an effects wheel while the other head is projecting the same frame on top of the effected projection.

you can see some effects like that in this old video that karl and i did.

I have some pics of the sphere opened up, about 8 posts back. The effects wheels are barely visible and rather hard to see because they are literally packed into a very tight space. Getting in there with a flashlight, there are are two discs each loaded with 5 smaller wheels. A few of the locations are empty, but most are populated. The two wheels are driven by rubber-tooth belts mated to what I think are DC servo motors or stepper motors. I'll try to get the camera in there which is harder to do now that the sphere is up on a pole. I have a hunch that the effect wheels mechanism is not much different than what Laserium has used, and numerous other of projector builders, just packed into a smaller space. The components inside are precision-machined and mounted in bearings.

[SpitzSTP]

Thanks Swami, I always learn more when you guys add comments and videos like these, it is a priviledge to see your work. I recall the old days, when after a show, I would always meander towards the projection booth and ask questions secretly hoping they would let me peek inside the projector. Of course, they NEVER would let me see anything and they never really told me anything either. So many lost weekends spent messing around with galvos stripped out of old chart recorders, scrounging around in junk bins at surplus stores, making crude home-brew galvo amplifiers with potentiometers and IC's from Radio Shack, stuck on a breadboard wondering--how DID they do that ??? Now all these years later, I see some of what was done by acquiring the equipment, taking it apart and seeing first hand what made this magic, never before being able to afford this stuff until it became fully depreciated, "old technology". Now it seems rather simple, although the magic is still there just not as much of a mystery as it once was. Getting ready to rack up another round of Hypnotica as soon as the sun goes down, glad not to be paying $8 to see it again, more like $4 counting the electricity and water I will consume to see it.

one of the primary differences between the omniscan and the laserium rigs i've seen is the laserium projectors can have multiple scan heads. this leads to some really cool effects because you can do things like have one head projecting through an effects wheel while the other head is projecting the same frame on top of the effected projection.

you can see some effects like that in this old video that karl and i did.

[polishedball]

Started working on things again early this morning to get ready for more shows tonight after the sun goes down. I finished hooking up the rest of the cables, including a pair from the Omniscan Key Box (labelled Effect In and Image In) to the Y-cable that goes to the back of the Pangolin card. Also, from the dataSYNC box (one cable from dataSYNC (labelled From ADAT/Sync Out) to the HD24 (Sync Out). Also ran a cable from the back of dataSYNC (labelled SMPTE Out) to the MQX Audio Card (SMPTE In). Hopefully this is correct, I guess I will find out unless anyone can suggest a way to determine this functionality beforehand. I finally figured out how to raise and lower the sphere using a switch on the Omniscan Key Box labelled "Aux", switch position up is up, down is down, found through trial and error as we have absolutely no documentation. I think there is also a way to do it through the software utility (pictured), the one I had to load Java runtime files for. The utility also seems to have a way to exercise the effects wheels, going to take half the cover off the sphere and play with it this afternoon and see if the effects wheels are operating. I emptied a good part of a can of WD-40 on the telescoping shaft and it is now going up and down very smoothly. I am on Win98SE as a limitation of the old Pangolin board, so I bought an old copy of Acronis True Image backup V.9 to backup this hard drive after many hours of hard work I cringe at the thought of losing it. I read on Wikipedia that the last version of Acronis compatible with Win89SE is V.9 but found out the hard way that nope, it isn't I need V.8. Dang Wikipedia I trusted it too much now I need to find an even older version. It is a royal pain in the arse messing with Win98SE but ye old wallet is preventing any forward progress in obtaining the new Pangolin board and migration to XP so I don't have a choice. With any luck, tonight's shows should be more interesting than last week's shows.

I use the datasync box, to slave HD24 to an LSX timeline. So is you have questions getting them hooked up lmk. I have done it both ways converting it to TC and read into the computer and also to midi over USB. I have also gotten it to slave to LD2000 and track. I just don't use that as Andrew modified LSX for my exact needs of TTL control. I use LSX to run all the effects and beam tables and its time line syncs to the HD24.

[DZ]

Went to the local planetarium to watch a couple full dome shows with the SkyLase. Got a couple pics of the projector and thought I'd share here. Hopefully these will show up surplus in another 10 years or so.

[SpitzSTP]

Hey thanks, wow! Great pictures! I have been curious to see this system up close. Did you enjoy the show? I need to get these gensets running as I tripped the breaker again right in the middle of Rob Zombie, it's either that or more than three of my neighbors flush their toilet at exactly the same time - either event has the same effect which is usually right in the middle of something intense. Karl recommended I start using the 50A oven outlet instead of the 30A dryer outlet, but by doing so, means I have to clean up 19 years of crud I imagine is under this appliance.

Went to the local planetarium to watch a couple full dome shows with the SkyLase. Got a couple pics of the projector and thought I'd share here. Hopefully these will show up surplus in another 10 years or so.

[DZ]

Hey thanks, wow! Great pictures! I have been curious to see this system up close.

I'd like to see the inside of one. I really wonder how they are able to keep the far field alignment so perfect along with the fact that all 3 colors produce the exact same spot size. I kinda wonder if there's fiber involved.

Did you enjoy the show?

The show was pretty good indeed. They do an amazing job with abstract!

I need to get these gensets running as I tripped the breaker again right in the middle of Rob Zombie, it's either that or more than three of my neighbors flush their toilet at exactly the same time - either event has the same effect which is usually right in the middle of something intense. Karl recommended I start using the 50A oven outlet instead of the 30A dryer outlet, but by doing so, means I have to clean up 19 years of crud I imagine is under this appliance.

We had a similar problem at SELEM when someone would flush a toilet. We had to change our water source and were able to solve the problem.

[Picasso]

I know a group who likes to phrase and worship such things if it ever comes out of the house. https://www.youtube.com/watch?v=SJcd6ZTIHVM