SOLUTION for Vraylight skylight portal problem...

[matt]

hi all,
i posted few days ago about this prob in the general board..but no answer, so here i come again with pics to show this "bug"

i made a test scene for interior lighting...here you can see the model

as you can see, i have 1 vray light in each opening (1 window and 2 roof openings), and a i have a direct light for the sun...

when i set the vraylights as skylight portal then the sun light is not computed in the iradiance map and global photon mapping

1) first pic with only vraylights ON (skylight portal turned on)= cloudy lighting


2)second pic with sun light turned ON

you can see that no light bounce for this sun light is computed

3)third pic: how it must be for a good light simulation,
here i must turn off the skylight portal for vraylights, and it's harder to set exactly the good multiplier for each opening if they are large or small, it's not as easy as playing with the environment multiplier and color in vray for all openings at the same time


so, you can try it by yourself, and tell me what you think...

i hope someone will find a solution

[losbellos]

hello, I think in the system menu, light settings you will find something about diffuse multiplier, try to increase that, (for PhotonMap) for the irradiance map it is strange that dont calculate. I think it should work.
(maybe try with only sunlight, remove the vraylights, this way you can get a clue what sunlight does itself, if u havent tried yet)

[matt]

thx for your reply losbellos
but it's not a prob of multiplier..i ofcourse tried to increase with very very hight value...

but the prob is that the vraylights are like planes that dont let the other light go through for the computed GI when the skylight portal option is turned ON

[cmejia]

have you tried to exclude the skylight portals from the sun????

let me know if that works for you....

[matt]

cmejia: the sun light is not a vraylight as you can see on the screenshot, it's a max target light (so no skylight portal for it).

for you all, here is my simple test scene:
http://membres.lycos.fr/xxmattxx/vray/int.max

[Da_elf]

i remember finding a bug at one point where vray lights block normal lights unless you set the vray lights to invisable

[Robert]

the Vray light is an object, so if you make it invisible, it's still there!

If you place in a window no light will enter from GI.

Well sounds strange, but remember that Vray can exclude objects from GI.

So the shadow of your sun, or better the light you see is handled like a raytrace effect, not a GI part.

There is no way in Vray to exclude any object from GI and Raytracing, however I haven't tried to exclude a Vray light from Raytracing...
But I had this problem once, when tried to simulate a ceiling with many lights. Well there was light then, but the ceiling was black...

regards,

robert

[matt]

Robert: thx for your help, but i said that the prob happen only when the SKYLIGHT PORTAL is ON, if it's turned off then the sun light enter and is computed in the GI.
you can see it in the third pic...

[RErender]

Portals are only useful when using a photon map, their main purpose is to generate photons from the skylight, photons from the "sun" will pass through and be calc'd. In looking closer at your set up I 'd have to say that no phptons from your sun are hitting the building . For photons you should use a target light and focus the hotspot on your target to ensure eficient use of your photons.

[matt]

Rerender: thx alote, i changed my sunlight with a target light and moved the target point inside the room, so now it works perfectly, it's incredible that the solution is to move the target point finaly!

if anyone is interested i can post my "interior lighting test scene" with photon mapping and GI final settings.

here the final pic :

about 20min to render, global photon map and irradiance map rendering time include

[DaForce]

i am interested. Great render BTW

[DeadlyAppearance]

I`m interested too, because i have a light problem too. See my post.

[cocolas]

yeah, I'd be interested as well


paul.

[matt]

ok here is the link guys:
http://membres.lycos.fr/xxmattxx/vray/int.max


enjoy

[RErender]

Glad that helped, I know that Vlado was considering a method to channel photons from a light through the portals, but until the then we have to do the "aiming".