sIBL - still confused

[voon]

I'm trying to build an environment with Blender for Octane - but I somehow don't understand the various sIBL files. There's the backgrounf. A jpg, just a foto, can be used as environment texture .. not a lot of light. There's the .env file, a blurred version of the background. This seems to be intended to use with an emission node to get less fireflies when used with say PMC.

Up to now I assume you'd create a mix texture of background and env, and use the env to intensify or lessen the light?

Then there's the HRD file .. loaded in Photoshop, this seems to be the same as the background, but with more intense light. I assume we're sort of supposed to use that ... someone wrote, Octane needs only one file out of the sIBL group (?). But how do you really use it? Loaded in octane, it is terribly dark. If I raise Power it gets acceptable, but it's bright areas are totally overexposing then.

I'm confused ... with this knowledge, i can get a halfassed newbie version of my stuff, but how is this REALLY supposed to be used in Octan (or octane for blender for that)?

[roeland]

In Octane for best effect you should load the big HDR file. If the gamma value is set to 2.2 after loading you should change it to 1.0.

--
Roeland

[Olitech]

Voon,

In other rendering packages, they typically use the BLURRY hdr for the ambient light, the HIGH RES hdr for the reflections. sIBL will also place a physical light in the right position for the direct light.

You don't need to do this in Octane. *High five* As Roeland says, just use the crisp, high res one.

Load it as an IMAGE MAP in the texture slot of the TEXTURE ENVIRONMENT. Use that to light your scene. Gamma of 2.2 will give you a high contrast. As suggested, change gamma to 1.0 and only increase slightly if you want more contrast.

Hope this helps.

best,
O

[voon]

Sure does .. I am working in Blender, but I found out how to create a new world Texture that uses nodes and then assign said texture as the worlds texture. Now I have to figure other weird stuff like resizing the car (or zoom in the camera) and wonder, what the right size and zoom is then for the text env, which always stays the same .... and how to create a plane under the 3D object, that is transparent, but still has shadows (i guess that's how you simulate shadows in the env texture environment. It's also weird how I can't bring my car down onto the "floor" of the background texture ... it obviously just floats at times, given the texture sphere around it Ah well ... new to this and it's a funky experiment, but looking fon ... panning the panoramas alone is interesting

[Olitech]

As long as you understand the fundamentals, you're well on your way...no matter what 3d package you are using.

Practice makes perfect!

Chuck Jones once said that it took around 100,000 bad drawings before you get a good one. After that, they're all good. Now, if we apply this rule to 3D computer graphics, and factoring in Moore's Law, carry the 2, maybe get that number down to say...100? =D

Better get cracking. ;^]

best,
O

[roeland]

sIBL will also place a physical light in the right position for the direct light

I missed this part, it requires both a sun emitter and a texture environment. This can't be done directly in Octane yet, you have to use a workaround like putting a big emitting disk at some distance from your scene.

--
Roeland

[riggles]

That's the beauty of Environment Importance Sampling. It basically replaces the need for sIBL's direct light source for sharp shadows. Plus, reducing the gamma gives you even more contrast and sharper shadows. sIBL was a nice placeholder, but it's expiration date has arrived, IMHO.