octaneLights, too dim for sun? Tweet

[neuro]

I've started blocking out a scene and when I determined the octaneSunSky might not be my best option, I figured I'd try adding an image/texture for the background (for the general sky look, like clouds and then I wanted to add a bright sun as a separate octane light. I tried cranking the light to a max (seems to not allow a higher number )power of 100000, but the light isn't anywhere bright enough to light up my scene. In other renderers it isn't unheard of to make lights super bright to approximate the sun, but with Octane I can't seem to get it bright enough to light my big outdoor environment.

Any idea how I might create an artificial bright source, like a sun, without the octaneSunSky?

thanks for any insight on this.

[neuro]

this really has me stumped. The lights have a plausible natural attenuation, but they seem severely limited with that arbitrary built in cap. For a small scene I suppose you won't run into this problem very often, but if you need a very bright light I can't seem to figure out how to get more energy. Maybe a diffuse shader with a texture in the emission?

Any ideas?

[bepeg4d]

hi,
for super bright light, you need to change also the efficiency and bring it to 1. Anyway, you can always augment the exposition a lot to correctly expose the fake sun. I have always used this method in the past when HDR+Physical Sun was not possible and it works pretty well
ciao beppe

[neuro]

augment, by exposing up the camera? I suppose that's worth a shot, will that cause octane to do more samples ronaccomedate the brighter illumination? I have the parameter at 1.0 as you say, but still dim.

Odd behavior. Things as bright as sun always being clamped seems like an odd limitation. Back to more testing and thank you.

[neuro]

ok, I think I have a good solution. Exposing up the camera did help, but even it had a limit of 4096 which wasn't enough. I ended up plugging in a multi node into the light's power input, bypassing the artificial UI limitation and now have a sufficiently powerful light, even with the exposure set to 1.0. Maybe an Otoy rep or developer can chime in, what's with the arbitrary limit built into the UI control? Hopefully just an oversight as in not sure how this helps users.