Dome light vs. environment light...

[studioDIM]

Some tests...

Kitchen.hdr as BG map + irmap primary only (settings posted later on):


No BG / GI, Direct computation, 24 subdivs, 1024 resolution:


No BG, IRMap GI primary only, store with irradiance map, 64 subdivs, 1024 resolution:


All in all, one more confirmation of VRay being an absolutely smacking all-rounder...

Lele

[davision]

I think I used the wrong terminology.

I see that the dome still has a direct component even when stored in GI. I guess I wasn't sure what exactly happened to the Direct Lighting once it got stored as an IRR map (vs. not stored and vs. the environment light).

Once the dome is stored in IRR -- is it susceptible to the same issues of splotchiness as the env.light?

ALso...

it is just stored with the irradiance map hence you can turn it off at rendertime to save rendertime

This isn't quite correct is it. You don't need to turn the light off. If it's stored in IRR and you're rendering from a pre-calced IRR file, the dome light is ignored anyway since it's baked in, right? Turning it off won't help anything will it?

[cpnichols]

if you are only interested in the primary light of the environment, you may not even need to turn on GI.

the only drawback is that in areas where the geometry in scene in not lit by direct light you get totally black surfaces (like parts of a model perfectly parallel to the ground plane).

Yeap... that is why I hate the concept of Ambient Occlusion so much. I talk about that on my DVDs. However, if you are doing character work which conditions such as these don't happen as much, GI is not as needed.

[cpnichols]

Some tests...



Lele

Now try your test with an HDR with a very bright source such as a direct sunlight.

[Sushidelic]

Apart from importance sampling threre's another great difference - domelight as beeing a light source is producing speculars, and as they are based on the map in this case real nice ones. They can be treated separately in render elements. Drawback is, that the "environmental lighting" is now stored in the lighting elements and no longer in gi.

regards,
Michael

[mmikee]

When using the dome light, how can I tell it to not effect the alpha ?
I still need to add pretty background footage in the animations.

Regards,
Mike

[davision]

Doesn't making it invisible work?

[mmikee]

I havent tried that, but then wouldnt you loose the specular from it ?
I really like the way exterior glass looks when using the dome light.

Regards,
Mike

[rivoli]

nope, unless you uncheck affect specular.

[mmikee]

Thanks rivoli. How about reflections ? If I have the dome light using a
HDRI for reflections on the glass, can I keep the reflections and still get
an alpha ?

Regards,
Mike

[rivoli]

yes, reflections will render just fine. actually I thought that was what you meant by speculars

[studioDIM]

Now try your test with an HDR with a very bright source such as a direct sunlight.

Indeed, Chris, it was wise to suggest that.
I was interested at how the shadows patterns resolved in that case of dimmer light, and the three methods lead to very very similar results.
When i rendered out a VRay sky with a dome camera, and mapped it back onto the domelight, some interesting things happened, however.
I also raised the resolution a bit to bias the tests a bit more towards the interpolated methods, not really at ease with tiny pictures (the opposite is true for direct methods like QMC of course).

Direct, 32 samples, noAA

Store with IrMap, same as above.

And here the surprise: same image as BG, pure IRmap (150Hsubdivs ( !! ), high preset)render without lights.


Since the hdr is comprised of a super-bright, tiny spot (the sun) and a comparatively under-bright sky, the standard BG method falls to pieces, where the importance sampling shines brightly, for both speed and quality.

Lele

[peakyfreak80]

I've been trying for a while here and can't seem to render out my VraySky through the DomeCam and have it work properly on the DomeLight.

Lele- can you share your settings for getting an hdr image out of the VraySky? My images looks fine, but when I attach it to the DomeLight, there are no shadows at all. So frustrating!!!

Thanks

peakyfreak