Amazing Diffraction Gratings - now rotating!

Almost a year ago I had the good fortune of discovering an envelope with the coolest diffraction gratings I had ever seen on my workbench. I don't know where I got them! Everyone that saw them said that they must be designed to rotate, but they are very small, only an inch or so square on plastic substrate.
Then I discovered David Kumpula's "Scan Thru Rotator". I purchased one, and after a lot of work and waiting, I have the device all working, and installed the gratings yesterday. Wow! I am very happy. I stitched together a sample video of all of the gratings to share with y'all - Tim

https://drive.google.com/file/d/1kwk...ew?usp=sharing

Tim,

I was cleaning out a planetarium storage area on a Chicago area campus, having been the only one to place a bid.
I found an envelope of custom gratings mounted in slide frames. Some of them look similar to what you have. A few were designed to be constellations. I'll dig them out in the morning and shoot some pictures.

Love the video.*retardo

Steve

Can't wait to see the trove you rescued :D

https://memegenerator.net/img/instances/59454589.jpg

Great video, Tim! Thanks for sharing.

Regarding the scan-thru rotator, was this a pull from one of the REKE / LK projectors from China, or is this the new rotator design that David worked on with Ed Keefe? (I know the new design was vastly superior, but I seem to remember it was a little pricey; maybe $500-600 ish.?.)

EDIT: Nevermind! I'm pretty sure it's the new rotator design that DK and Ed came up with!

Assuming that you went with the newly designed unit, did you go with the stepper motor version or the one that uses a standard DC motor?

Also, love the room-filling lumia you've got! :)

Adam

PS: This post just reminded me that I need to get in touch with Greg Southerland and see if he's got any more of that shower glass left. Been meaning to build a lumia rig for a while now, and I finally dug out some of the weird wavelength lasers I have in my stash (488 nm dpss & 575 nm dpss) so I could start laying things out. But I don't want to sacrifice the one nice stand-alone lumia wheel I have, so I need to see about getting another one from Greg.

Great video!

Can we got some pictures of the gratings with just a stationary dot through them? Also pictures of the setup for those of us not familiar with the scan thru rotator would be great!

Thanks for sharing.

Quote:

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Originally Posted by LaserWizard

Almost a year ago I had the good fortune of discovering an envelope with the coolest diffraction gratings I had ever seen on my workbench. I don't know where I got them! Everyone that saw them said that they must be designed to rotate, but they are very small, only an inch or so square on plastic substrate.
Then I discovered David Kumpula's "Scan Thru Rotator". I purchased one, and after a lot of work and waiting, I have the device all working, and installed the gratings yesterday. Wow! I am very happy. I stitched together a sample video of all of the gratings to share with y'all - Tim

https://drive.google.com/file/d/1kwk...ew?usp=sharing

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Hey guys! I haven't been in PL for many months, but I'm pleased to see Tim making use of the Scan-Thru Rotator (STR). (Ed Keefe deserves 99% of the credit for creating this cool tool, by the way. He's a genius!)

Tim (and PolishedBall) waited patiently as we worked through an error with the two-stepper motor version of the STR that we missed for a 7-position lumia wheel. Thankfully, we finally got them up and running and I'm pleased that Tim's results are so stellar with those cool gratings. I've got four installed in my small home environment, but I'm planning on adding a couple more. In my opinion, there is no such thing as "too much lumia"! :)

-David

Quote:

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Originally Posted by dkumpula

Hey guys! I haven't been in PL for many months, but I'm pleased to see Tim making use of the Scan-Thru Rotator (STR). (Ed Keefe deserves 99% of the credit for creating this cool tool, by the way. He's a genius!)

Tim (and PolishedBall) waited patiently as we worked through an error with the two-stepper motor version of the STR that we missed for a 7-position lumia wheel. Thankfully, we finally got them up and running and I'm pleased that Tim's results are so stellar with those cool gratings. I've got four installed in my small home environment, but I'm planning on adding a couple more. In my opinion, there is no such thing as "too much lumia"! :)

-David

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try nine color lumia….too much lumia

The Photonotron I brought to SELEM has 6 colors, inspired by you guys.

Thanks!

…Mike

That is awesome, thank you for sharing.

Great video, Tim 🤯
As it happens, I'm currently developing a unique, new, 'improved' rotating scan through lumia fx attachment for mounting onto the front of RGB projectors.
4 X independent, variable-speed, rotational lumia fx, translating in/out of image path, providing 16 optional (theoretical) combinations.
To that end, I'm also seeking any/all sources for an assortment of 2" large diffraction gratings, if anyone can help.
BR
Roj

Greg Southerland (Displaser) had some cool lenticular plastic that would probably work well with your 4x rotator design... Might want to ping him and see if he's got any of that material left in his stash!

Adam