Theatrical Lighting in V-Ray: Laser Fixture Kvant 30W RGB

[dpwr]

I'm trying to render laser light for a corporate event. There doesn't seem to be an .IES file for this instrument, and looking through the .IES library (https://ieslibrary.com) I'm not seeing anything close to this effect.

I can do this afterward in Photoshop, but I'm interested in trying this in V-Ray.

Line lights could fake some of the effect, but they won't thin and degrade like the laser does. This was helpful for the tight beam effect, but it's in RenderZone: 

 

Has anyone tackled the fan/cone lasers with gradient color before? Thanks!

 

Edited October 27, 2023 by dpwr

[Justin Montoya]

Hey DP, how are you?

That's a cool effect.  I like a challenge so I figured I'd see what I could create that would look like a laser beam.  I also stumbled across this post on Reddit where some math gal gave away some laser IES files she created -  more info on Thea page

 

https://imgur.com/gallery/7o0Wa6X

 

Then, I created (5) narrow angle spot lights with incredibly high intensity.  Using Atmospheric fog to show them as well.

I don't know your needs exactly, but if it were me, I'd just use the narrow spot light here as the IES beam file doesn't seem to work well.  The creator mentions using the IES file on a surface, so maybe it needs to pass through a piece of glass or something??

The scan ies file is interesting though. 

My guess is that an IES file could be created to do exactly what you want, but you may need to get into some heavy mathematics to do so.  Or there's also a few IES editor apps out there, so you might be able to use one of those to load these files into them and then manipulate with a nicer UI.

That's where I got in a short trial.  I think you could also use some invisible mesh lights mapped with a gradient to create the other parts of the cool laser show.  

Let us know if you figure something out?   For the greater good?

Laser-Beam.ies Laser-Narrow.ies Laser-Scan.ies Laser-Wide.ies Laser light test-1.fmz

[dpwr]

Wow! You DO like a challenge. Thanks for investigating this. I watched a few videos but they were specific to Maya and 3DStudio and found our version of v-ray was lacking the same tools.

I'll add these in and share what happens. Thanks for helping with this!

 

[dpwr]

The quick report on results is that I struggled.

I was able to open and render your example file perfectly.

I copy/pasted the lights into my working file. This environment was basically the one you created in 2021 for v-ray theatrical lighting. The laser lights pasted in without needing to be scaled or adjusted. The lasers here were not very visible or rendered as dots/particles instead of beams. I compared the environment fog settings between our two files and made adjustments with he same render result. I compared other v-ray settings and didn't se anything that would explain the particles. I also turned off all lights except for the lasers to see if other lighting was affecting them, and got the same result.

I'm happy to send the file/images over if you're curious to see. I can also try to neutralize NDA stuff in them and post them here later.

As a work around, I renders the lasers separately as objects and added them in Photoshop to meet a deadline. But I would love to understand how to create better theatrical lighting effects in FormZ and v-ray.

More later!

Edited November 6, 2023 by dpwr

[dpwr]

[dpwr]

Some overhead lights are off, lasers still grainy.

[Justin Montoya]

Interesting.  I believe if you were to let your rendering run long enough, the laser spot lights would render clear without grain.  But this may not be reasonable given the timeframe?

When I rendered my test, setting the VRay Quality to Very High was done to show accuracy and capability.  This inevitably renders slower than setting the Quality to say Medium.  What setting are you using?  I think given the low light scene and desire to show accurate tiny laser like lights are going to be tricky.  I think you may want to experiment with using the Light Cache for Primary Rays AND Secondary Rays.  When I did that, the rendering of the lasers was a bit quicker, but this would likely not give a rendering of the whole scene you'd like.  However, you could render just a version for these lights, then save their Channels and composite them in Photoshop with the other image.  Not ideal, but it may be better than you have so far?

I suspect we can find a setting that works more reasonably for you.  Also, slightly increasing the laser spots inner angle may speed this up a little as well.  Lots of settings to try...