Emulating the light properties of a fluorescent tubed light fixture?

[Mylenium]

[Michael Munkittrick] “1. How would I go about creating a soft-white emanating light source from the filament outward?
2. How do I get that light source to cast its light on objects within a scene?”

Not particularly pertaining to C4D but more to 3D in general: Those effects usually require global illumination. You’d model your neon and then give it some luminosity and the GI render does the rest. The thing is, that GI is usually a very slow process – depending on the complexity of the scene, even a single frame at SD res can take hours. So usually you calculate this info only once and then either cache it or bake it to a texture map. You could also get away by placing multiple tube area lights along your profile.

[Michael Munkittrick] “3. And what is the proper way to rig the model so that the control for multiple light sources can be done from a singular step as opposed to going down through my hierarchy?”

In case of “real” GI that wouldn’t be a problem since it would be a property of one single material. If you use multiple light sources, you could probaly link the using XPresso or a custom attribute. Dunno that for sure since I’m only playing with the demo of 9.6 and don’t have the money for the real thing…. :-\ Oh man, I should have stuchk with C4D instead of LW… *sigh*

Mylenium

[Pour Myl

[Michael Munkittrick]

I suspected GI right off the bat, but there was a glimmer of hope that I could fake it with another feature that I’m too dense to have found as of yet. I don’t mind going the long way ’round but if there were a shortcut, I’d like to try it.

As for the rigging of the light sources, I kept thinking that parenting with a script might do the trick, but there doesn’t seem to be a pre-existing script to make this fuction as I was hoping.

Considering that I’ve made up my mind to buy the advanced render, mocca and sketch/toon modules (and the mograph when the cash comes around) I should really learn some basics of scripting anyway I guess.

I sincerely thank you for your time and helpful information.

Cheers!!

Michael Munkittrick
Gainesville, Florida USA

[Adam Trachtenberg]

You can use standard lights instead of (or in addition to) GI. Create a light and set the type to Area. Then in the lights details tab, set the area shape to Line. The light itself won’t show up in the render, so you’ll have to create a cylinder around it and exclude it in the light’s Scene tab.

Another option is to use the cylinder itself as the light source. So, instead of choosing Line as the area shape, choose “Object/Spline”, and drag your cylinder into the object box. Then check “Show in Render” below that.

As for controlling multiple lights at once, you can either do it via Xpresso, or by simply selecting multiple lights at once and changing the parameters in the attributes manager. You can do this in a relative way by typing x*(multiplier) in the parameter fields. For example, if you have a light with brightness of 100% and another at 50%, and you want to reduce the combined illumination by 50%, you would select both lights and type in the brightness field “x*.5”. If you then examine the individual lights, you’ll see that one has a brightness of 50% and the other is at 25%.

You can use a Selection Object to improve workflow. Add one to your scene, drag in all your lights, and henceforth you just have to double-click the selection object to select all your lights at once.

In addition, there is a global brightness control in Render Settings>Options.

Finally, if you use AE or another compositor, you can use multipass and output a separate pass for all your lights. This allows you to adjust brightness and even light color after the fact, and in real time.

[Michael Munkittrick]

[Adam Trachtenberg] “Another option is to use the cylinder itself as the light source.”

This was my initial idea, but the light does not seem to keep within the parameters that I set for it. I was trying to use a cylinder as the body of the bulb and a tube to contain the focus, but the tube seems to be of no use. Is there a way to use a mirror material on the inside of the tube and then map a flat, textured black shell with no transparency?

[Adam Trachtenberg] “This allows you to adjust brightness and even light color after the fact, and in real time.”

Now THIS is a tool that will come in handy. I was aware of the integration between C4D and AE, but layer mods in live time is just too sweet to not have comprehension of.

Thank you again for your help.

Michael Munkittrick
Gainesville, Florida USA

[Chris Smith]

You can download my “CS Objects”. I have a handful of simple tools to help with lighting and animation. I made 2 objects. One simply is just an area light in the shape of a kino tube. But check out CS_KinoSquare. It’s an array of 4 tubes that has a lot of Xpresso attached to make it a quick and easy set and forget rig for quick florescent looking lighting.

Check it out here at C4D Cafe:

https://www.c4dcafe.com/ipb/index.php?download=267

Chris Smith
https://www.sugarfilmproduction.com

[Michael Munkittrick]

Chris, I’d love to give them a try, but the page states that I am not permitted to download that file. I am a registered user now, but I can’t find a download link. How do I go about that?

Michael Munkittrick
Gainesville, Florida USA

[Chris Smith]

You can just download it directly from my site:

https://www.sugarfilmproduction.com/CS_C4D.zip

Chris Smith
https://www.sugarfilmproduction.com

[Chris Smith]

For future ref, at the bottomof any of the C4D Cafe pages there is a legal block of text, then you select “I agree, download now”

Chris Smith
https://www.sugarfilmproduction.com

[Michael Munkittrick]

That’s the craziest thing. That option wasn’t there when I logged in the other day. I reset my account and low and behold, there it is.

Thanks so much…

Michael Munkittrick
Gainesville, Florida USA