Indigo Renderer Forum

Hey

I try to create emitter sun first time, but i get an error:
IndigoDriverExcep: SceneLoaderExcep: TinyXmlWrapper: could not find element 'center' in element 'atmosphere' (around line 91).

Meelis wrote:Hey

I try to create emitter sun first time, but i get an error:
IndigoDriverExcep: SceneLoaderExcep: TinyXmlWrapper: could not find element 'center' in element 'atmosphere' (around line 91).

what indigo and blendigo version do you use?

Blender 2.48a
indigo_x64_v1.1.18 Windows Vista
blendigo v1.1.14
-----------------------

I wanted my sun to be lower colour temperature than default @ that position where i can see it on scene.
Allsoo i need the sky to be more blue.
So i have to use custom background and for sun type basic emitter (what looked not blended in with sky = with no sky = black,,, but will sun basic emitter blend in with background)

Soon 2.xxx Soon

Meelis wrote:Blender 2.48a
indigo_x64_v1.1.18 Windows Vista
blendigo v1.1.14
-----------------------

I wanted my sun to be lower colour temperature than default @ that position where i can see it on scene.
Allsoo i need the sky to be more blue.
So i have to use custom background and for sun type basic emitter (what looked not blended in with sky = with no sky = black,,, but will sun basic emitter blend in with background)

Soon 2.xxx Soon

first: blendigo 1.1.14 work not properly with indigo 1.1.b18. please download blendigo 1.1.18 http://www.indigorenderer.com/forum/vie ... f=8&t=5775
second: you can't change sun's temperature. if you need lower color space, use environment map

Thanks

I try this HDR thing out with newer blendigo when my fluids baking finishes.
---
When i set sun positsion with Fiat Lux http://wiki.blender.org/index.php/Exten ... s/Fiat_Lux
and i know measured data of apparent light intensity (Lux) in that time,
how to correct apparent light power from sun power in blender, or how mutch light does indigo sun output in x positsion (is there some short ~formula)?

Meelis wrote: When i set sun positsion with Fiat Lux http://wiki.blender.org/index.php/Exten ... s/Fiat_Lux
and i know measured data of apparent light intensity (Lux) in that time,
how to correct apparent light power from sun power in blender, or how mutch light does indigo sun output in x positsion (is there some short ~formula)?

There's no particularly short formula.
Indigo used to print out the zenith sky luminance, and also the spectral radiance of the sun radiation at 500nm, but I'm not sure if that's helpful to you.

And actually if you look at the render log, you will see something like this:

Light luminous flux (geometry name=mesh1): 6.283E+004 lm
Light luminous flux (geometry name=EnvSphereGeometry): 1.479E+010 lm

Which tells you the luminous flux emitted from all light sources in the scene.

It's way too complicated for me.
I fond this url:
http://mysite.du.edu/~jcalvert/optics/lumens.htm
There is written: The luminance of the sun is about 1.6 x 10^9 cd/m2, and its angular subtense is δ = 0.5° = 8.73 x 10^-3 rad. Therefore, E = 96,000 lux on a surface normal to the sun's rays, or 62,000 lux on the level ground when the sun's elevation is 50°.

I have max ~75 000 Lux in midday.
96K / 75K = 1.28 ->
-> 1.6 x 10^9 / 1.28 = 1.25 x 10^9 lm
now when indigo render log shows 1.479E+010 lm ->
1.25 / 1.479 = 0.845 = sun power from blender default 1.

But my calculations are more likely wrong.