vray light:dome -how does it work?

[paulison]

wow thats very cool!

Sorry I missed that you had used GI, but isnt the point of the dome light to fake radiosity so that you dont need to calculate the GI ?

will try out higher subdivisons...because with render times like that and this quality result, I think that is more than enough than many clients are looking for (for exteriors)

[vlado]

Sorry I missed that you had used GI, but isnt the point of the dome light to fake radiosity so that you dont need to calculate the GI?

Nope, the dome light is not a replacement for GI, but you can use it with GI quite successfully. In this case, you have very good details for the sky shadows plus the color bleeding from the GI. The dome light was actually created for a specific case, where I needed good sky shadows but I wanted to use the lightmap for fast/smooth GI (it was an animation).

Best regards,
Vlado

[TishoChaos]

Hi!

I see this thread happened to be very alive, so I decided to explain again on the dome light after I did that couple of builds ago. So, like Vlado said, the purpose of the Dome Light is not to fake radiosity. What it does is to cast light rays from everywhere around the scene, producing the effect of a sky lighting. It doesn't produce Indirect Illumination of rays, as GI does. Here are some images that you may find helpful and informative:

Default max Lighting Default max Lighting + GI (Irmap + QMC):


Dome Light + GI (Irmap only) Dome Light + GI (Irmap + QMC)


Rotated Dome Light + GI (Irmap + QMC):


Dome Light ONLY Rotated Dome Light ONLY:


Notes: First, there are two images with default Max Lighting. You can see the GI bounces on the secondary image (color bleed). Then on the second row - GI with Dome Light which produces a nice effect, all the Dome Light's rays are given Secondary Illumination. The Image with QMC is slightly lighter than the one with Irmap only, because there are Secondary Bounces in it. On the last row, there is no GI, you can see the difference.

[Trapezium]

Hey Tisho thanks for the examples.
What's the "Rotated DomeLight" do?

--Jon

[silver]

hey trapezium, lol, it just do nothing... what does tisho said is that the example is with the dome light rotated from your source position , only to achieve a more diagonal light

[Trapezium]

Hey silver thanks but I don't follow what you're saying...

You said is does nothing but yet it gives more diagonal light??? I may have to just do some tests. How exactly was it rotated 45 or 90?

--Jon

[CCS]

Trapezium-

I believe what he is trying to say is that rotating the vray dome light creates shadows in a specific direction rather than directly beneath the object (noon).

You can kind of see it in Tisho's example above. I believe a recall an earlier post by Tisho that portrayed it a little more obviously.

[Da_elf]

sweet examples. shame there are no render times. but i guess it was still pretty quick render times for these.

[TishoChaos]

Hi! Jon, the rotated light is not another kind of VrayLight, it is just a Dome Light rotated on some degrees (40-50) according to the default position that you put in the Top viewport in Max. I posted that just to show to the people that it matters the rotation of the dome light, but the position does NOT matter. Maybe this is so simple and obvious that it confuses people - sorry if this is the case.

Elf, sorry for not posting the render times - they were some seconds for the toughest ones (Dome light + GI) and for the ones with the default max light - do we need them?

Expect more this week ...

[GALACTUS]

I like the new dome light, but people keep refering to ambient occlusion as sky light, is this not wrong? The ambient occlusion map in max7 (mental ray) is able to generate light and shadow information for both exteriors and of note interiors, these "interiors" to my knowledge cannot be achieved with skylight or dome light. I think it is a shader that takes into account mesh data when shooting ray into the scene and then works out which polygons occlude the ray and which don't and then figures out which areas would be dark and which would be light. (vague interpretation) and essentially the results end up like you have put a grey material into the vray overide material rendered your external scene and used the resulting images as your shadow pass in any compositor.

Any hoo Love the new domelight.

Cheers

Colin

[Da_elf]

from allllll the posts i was able to read on ambient occlusion it seems more that its closer to what something like dirt-reyes by infographica used to give.