Mixed Abstract and Graphics for Planetarium

[billwx]

OK, guts it is!
Here's the "monster" as I like to call it, before the change to solid state: (I drew in the "beams" to show how it worked.)


And after..


And another one..


Note the power levels are NOT "megawatts". We actually don't want anything superbright because we're mixing the laser images with the stars of the planetarium.
If anyone would like to see a new module I made last night of Pink Floyd's "Comfortably Numb", I've used the Pangolin AVI video output feature and converted a clip to mov format. It's right here.
(The frame rates dropped during the conversion, but you get the idea. You also don't see where I would have lumia and diffraction effects through the DMX.)
Happy viewing.

-Bill

[ImageLight]

Awesome pics, I love how you still use the AOMs for blanking. A foot in the old and a
foot in the new technology.

[mophead]

Very nice.

Thanks for sharing.

[billwx]

Awesome pics, I love how you still use the AOMs for blanking. A foot in the old and a
foot in the new technology.

Yes, we decided to continue to use them and do a straight swap of gas tubes to solid state. The AOM waste beam is actually used for the lumia effect. For those who've never used them, the laser has to be lined up "just right" through the AOM. Out the other end is the variable/blanking beam AND a "waste beam". The way the projector is set up is the waste beam is right under the used beam at a slight angle. By the time it's about to go to the main scanners, there's about a 4mm gap between them. Look at the beam path in the "before" image - just before the Cambridge scanners. It looks like 2 motors. One (on right) is a motor used to open/close the shutter for lumia (run by DMX), the other is the motor used to actually turn the lumia wheel. (It stays on all the time the projector is on.) The little "arm" that's sticking out between them has a small mirror at the end. It's adjusted to just capture the waste beam and direct it out through a hole and through the lumia wheel. So for lumia effect, the wheel is already turning, so DMX just makes the shutter motor flip a piece of metal up and down to block/unblock the beam. A simple yet effective use of the waste beam!
There is a green waste beam that's not used for anything that you can see in the last picture.
You'll also notice there was no need to split the blue/green from the argon anymore, so those diodes go straight to the blue and green AOMs directly. (I removed those optics that weren't needed anymore.
Notice too that the solid state red diode is actually held in place (quite securely!) in one of the old HeNe brackets! We built aluminum platforms for the blue and green heads so they could dissipate heat and be the correct height to work like the argon. One thing you don't see is I added a 120v 6" fan behind and at an angle between the green and blue heads to help with heat dissipation. Once we had everything together and put the cover on, the blue was getting too hot and fading after about 35 minutes. With the added fan, all runs cool and we have had NO color fading or the diodes acting funny at all.
One person on staff left the laser projector on overnight by accident a few months ago, and when I came in the next morning everything was still running normally. (Not even a burnt hole anywhere! )
The "new" system therefore uses the old system and simply replaces the laser part and everyone loves the "better" colors since we switched to solid state.
Now some trivia for those who want to think! The lumia effect uses the waste beam from all 3 colors - which are at a very small different angle (so we do get red, green and blue producing it's own beam - but very close to each other). The AOMs are adjusted so the main projector beam produces white graphics/patterns when we need them. BUT notice the red diode is putting out 200mW and green and blue are 100mW each. Obviously green and blue appear MUCH brighter - even with the 100mW difference. We have no control over the waste beam from the AOMs. (They are "waste" beams remember!) So how do you think I balanced the red, green and blue for the lumia so the blue and green weren't superbright and overpowered the red?! (Even brighter than the balanced color scanned images.)
Hint: When I first saw how bright the blue and green waste beams were, I figured out the answer in 10 seconds and fixed the problem in less than 5 minutes!

-Bill

[ImageLight]

Hmmm,

Maybe a pass green and blue / reflect red dicro as your last turning mirror before
the lumia wheel. This would still give enough green and blue off the front side the
dicro for the effect while giving full power to the red beam.

Mark

[billwx]

Hmmm,

Maybe a pass green and blue / reflect red dicro as your last turning mirror before
the lumia wheel. This would still give enough green and blue off the front side the
dicro for the effect while giving full power to the red beam.

Mark

Good idea, but I needed to get the projector up and running fast. As in - show in 15 minutes! Since in the planetarium we deal with "dark" issues all the time, we're used to all kinds of filtering/light blocking. So it was (and still is to this day) an easy fix. Simply taped a light red filter in front of the lumia - right on the outer case. We had a bunch of filters, so I simply taped on the one that did the best job.
It's been a year and nothing has burned, melted or otherwise gone wrong. As it turned out, the filter that worked best was plastic and flexible and had some small creases in it. So it actually adds to the lumia effect a little.
-Bill

[soforene]

...We had a bunch of filters, so I simply taped on the one that did the best job.
It's been a year and nothing has burned, melted or otherwise gone wrong.

Sounds like "seat of your Pants" lasering.
You'd fit in well at a LEM.

[ImageLight]

Sounds like "seat of your Pants" lasering.
You'd fit in well at a LEM.

I agree. Bill, you must come to SELEM in August. I think you'd have a great time there.

Mark

[buffo]

Seconded! There will be a good bit of equipment on display, both old and new, and lots of cool people to hang out with. Give it some serious thought, anyway. It will make a hell of a fun weekend vacation!

Adam

[billwx]

Greetings!

I've been busy the last few weeks with school programs and such. Not only do I do planetarium laser shows, but the sky shows, too. Keeps me busy.
Anyway, I was given the "green light" to share a new song module for a show this summer. It's one of my "smallest" modules - less than 25 Pangolin frames! It's "Better Now" by Collective Soul. I just uploaded it to the FTP server under the shows/Pangolin LD2K folder as "betternow.zip" - it does contain a low bitrate mp3 of the audio in case anyone hasn't heard it. I included a text file with details and a note on the DMX channel that's used in the module. It's a very simple, yet effective module - and took only 30 mins to create. Most take 2 hrs or more per song.
Enjoy!

-Bill