Can't change light intensity - help!

[lonny]

Hello,

I'm running Indigo 3.6.24 in Cinema 15.057 (64 bit) and I can't change light intensity or material emission strength.

Base Emission from the manual - I can't find such setting for Indigo Material in Material editor, only Emisson tab. When I tick it, material emits and I can change color of emission, but thats it.

Also. if I have multiple emitters in the scene, lights or objects or both, and change only one's Light Spectrum Type to anything other than RGB, all others stop emitting.

I attached simple scene and a render with two lights and two emitting objects. Emission values are extreme, but I keep getting the same result.

At this point I'm just hoping that I'm being super dumb and missing something very obvious...

Hope someone can help.

Thanks,
Lonny

[Zom-B]

You have no camera with a camera tag in your scene, so on export a default camera gets created with Reinhard tonemapping setting.
Reinhard tonemapping is bad for tewaking lights!
Simply use linear or camera tonemapping.

Also consider to update to the latest Indigo & Exporter Build:
http://www.indigorenderer.com/forum/vie ... =1&t=13177
http://www.indigorenderer.com/forum/vie ... 10&t=13125

[lonny]

My mistake, I forgot to mention this...

Yes, there is no camera tag because I get the same results with or without it.

I played around with tonemapping for couple of hours yesterday. Reinhard is the only one that works. In the attached scene I have to use Linear (Pre) Scale value of 2147483647 just to get some faint light (that's the largest number Cinema lets me input). With Camera tonemapping, not even values in the milions for ISO and EV Adjust settings gave me any light. And I don't think it's supposed to works like that.

I used Maxwell for a couple of years so I'm no stranger to unbiased rendering. That's why this is so frustrating... Indigo seems like a much faster solution than Maxwell, if it only worked for me.

Thanks for the suggestion, I'll try 3.8.8 update, didn't know it was already out.

[lonny]

Tried the new update. Still having the same problems, except now lights don't work at all - I can only get objects to emit.

Maybe there's something wrong with Cinema installation?

[Zom-B]

You set your emission scale very (!) different on each light Tag and material.
Don't use spheres as emitters, convert them to mesh first, since otherwise they get therated as primitives with "strange" results for emittance.

Don't use lights with Indigo Light Tag on them as emitters, better to do mesh emitters... always!
the tinny emitters created by C4D lights are rendering very slow in complex scenarios.

Some of the Light Normalisation modes are related to the scale of the mesh emitter!
I find them hard to use and prefer tweaking the uniform > value for blackbody > gain and for RGB > Brightness (way over 100%, try setting it to 10000% etc.)

And use linear tonemapping for setting up your lights, Reinhard is no help here, but causes rather problems in the end (noise)!

BTW: this Thread (just started) covers the same stuff you have problems with: http://www.indigorenderer.com/forum/vie ... 74#p128474

[lonny]

Yeah, Emission Scale is all over the place - I wanted to see if it will make any difference on light intensity. It didn't...

I use photometric units a lot when I do optical design. You should give them a try - they make lighting much more sensful. Lumens are great since they are size independent. 100w incandescent light bulb is around 1600 lumens. That makes it easy (at least for me) to create lighting with realistic light sources.

Anyway, looks like you solved my problem! Converting primitives to mesh did the trick - looks like everything is working like it should. And with 1000lm source Linear Pre Scale value makes much more sense with 20000 giving nice, bright interior with defult EV.

I can't recall if this is mentioned in the manual... Such a small detail, but it really ruined my day yesterday and today I was ready to call it quits.

Zom-B, thank you so much for your time!

[pixie]

Try working with indigo's camera tag 'exposure duration', set it to (0.0001), it might help too. Also try using light 'normaliztion' luminous flux, this way you have the same light power independent of the size of the emiter.