Thu Dec 14, 2006 post in CHAOSGROUP FORUM tutorial aproach in other light situations

[jfs]

After watching these videos, and make some renders with these strict to real life material / light behavior, i asked myself if these would be possible to apply in other light situation usings the Physical Camera and if there will be advantages of it... I love the dome light with HDRI texture in exterior scenes, and was curious to know if the white swatch of the Falloff Map in Reflections should be replaced with the VRayColor Map white 0.255 (i leave black 0.000 = 0 no VRayColor Map)? Regular materials should handle this strait but what about glass and chrome?

 

 

This image is lit by a dome light with the Paul Debevec Grace Cathedral Probe as VRayHDRI tex multiplied by 50 (so i can get close to the method and had a strong intensity light from the HDRI), with 3 materials:

 

white

0.255 VRayColor in Difuse

0.255 VRayColor in the Falloff White Swatch (Reflection Map Falloff - Fresnel - Override IOR 1,60)

 

 

glass

0.255 VRayColor in the Falloff White Swatch (Reflection Map Falloff - Fresnel - Override IOR 1,53)

0.255 VRayColor in the Refraction Map

 

chrome

0.255 VRayColor in the Falloff White Swatch (Reflection Map Falloff - Fresnel - Override IOR 2,00)

 

The results are encouradging - the chrome and the regular materials behaviour is good, but the glass... hummm still have to try with other HDR to know if some glow effect is from the colors of the cathedral or not...

 

Does anyone tryed this aproach to?

 

Sincerely,

Joao

 

PS: let me thank all of you how excahnge experiences in here and let other, like me, whoa are begining, to learn faster and in the right direction.

[jfs]

 

Changed the HDRI (Used the Eucalyptus Grove from Debevec's Probe Gallery, and aplied a 10x multiplier because this image has a stronger light - should use 15x) and the glass is behaving well (i think)... Also remove Reflective GI - in the Indirect Illumination rollout - that was causing the light splatches from the glass cilinder to the ground (caustics are OFF in both images)

 

Once again thanks all.

 

Sincerely,

Joao

[AJLynn]

I actually liked the first one better, mainly because of the GI caustics. Are you sure they're not correct? You could use refractive GI caustics as well and turn up the GI quality a bit higher. With a close up of 4 simple objects you need all the realism you can get from the lighting and materials.

 

Nice materials BTW. Try harder ones now.

[jophus14]

I seen those videos about a week ago and when finished, I was quite confused. It seems like a lot of work and calculating in order to get textures and lighting to match up. The videos were great and they explained a lot, but it seemed like a lot of work overall. How did you all feel about the videos?

[kippu]

very confused .... i am not so good in calculating and using numbers ... and as far as the old methods work .why fix it?

[jfs]

@AJLynn

Hi and thanks for your comment. My goal here was not a aesthetic result but rather an avaliation if the VRayColor (real life darker than they seem) method with high intensity lights (like in real life sun) woud work by aplying VRayColor with 0,xxx not only to the difuse, but also the reflection, falloff, refraction, ..., color values.

 

@jophus14

You are right! At least for starting a new workflow aproach... I think if this is the right way to work with VRay (and I rarely render with other engine) in a few months this will be automated (like any thing else). In the videos I liked the feeling of controling an image output like we do in photography, thats the main reason why I'm trying to understand if this is the way...

 

@kippu

If the development of VRay keeps adding features based on these principals, I think in the future it will be much easier to work with VRayColor aplied to materials, rather than change all lights, camera, ..., in order to get a correct exposure, dont you think kippu? Of course, having in mind that VRay is the render used 90% of the time.

 

I want to take a good look at this workflow and test a lot... Hope this weekend can post here some test images and exchange ideas with you.

 

Sincerely,

Joao