Best light setup to test materials

[rsquires]

I'd be interested in peoples thoughts about light settings for testing materials. Today I tried to light a scene with the physical sun. I had a simple material that was based on a photo I took of some wood. I had a bitmap in the diffuse channel at 100% and no other layers. When I rendered the image it was hugely blown out even when I applied some color mapping. I am not sure if this was to do with the scale of the scene or what but it was really crummy. Anyway by the end of the day I have a scene I am very happy with but I'd love some way of testing my materials in an environment that gives a true idea of what your textures look like. I know there is a test scene and I downloaded this but it would be nice to hear how other people do this

regards

richard

[1066]

Have you tried the Material Sample Scene?

http://www.forum.vrayforc4d.com/viewtopic.php?t=178

EDIT: Sorry I didn't read the end of your post :o Disregard my post above.

Not that I know much about VRay but I set up a scene where a sphere, cube, and various other objects are placed inside a larger cube with holes cut in the side at various points. I then add a Physical sun etc and position the box so that through the Physical camera, light and dark areas can be seen. Then I position multiple copies of the smaller objects in both dark and light areas, near and far so that I can get an idea whether or not they look good in all situations.

[simonw]

i would imagine that if you are using the physical sky to light your scene then you would also use the physical camera to render through. you should then be able to use the exposure controls to bring down the exposure of your scene to more sensible levels just as you would with a real camera.

this would maintain the calibration of your set-up so what you get would be valid for other scenes.

cheers, simon w.

[rsquires]

Hi Simon,

I'll give that a go and see what happens. I think the Material Sample scene is a good way to test stuff. It seems pretty universal in it's lighting and reflections.


regards

rich

[stefan]

i soon post a calibrated scene.

it is not to easy and needs some time to tune.

important is:
there may not be light color in it and it must be even lit, but still have enough contrast.
also it must have speculars and things to reflect.

it needs flat, cylindrical, spherical areas and roundings with different radii.

most scenes, aslo the one of vraymaterials.de look nice but are worthless as they use colored hdris in reflection etc. so the matial looks cool there but not when you use it in other kind of scenes.

i hope not too far i can upload it

cheers
stefan

[Laurent]

a vray material preview would be a great enhancement. the basic create "vraymaterial" with sun+sky renders 100% white! it should behave like c4d basic material or we need to set our camera to bottom-of-coal-mine-at-night settings.

[stefan]

use colormapping an camera!
also adjust sun intesity if you want:-)
the raw settings is a bit overblown

cheers
stefan

[rsquires]

the raw settings is a bit overblown

cheers
stefan

I thought that too but didn't want to say. I didn't know you were able to adjust the intensity of the sun light. When I go to change the colour it defaults back to what it was. I seem to remember there being a check box about light color so maybe I'll check that out. I think a properly calibrated scene would be very useful

regards

rich

[Tong]

Don`t adjust the intensity of the sun light, it`s wrong way for you now (not, if you want to change the time of day - basicly it by Height of Sun), adjust the way of "photographing" of image by your camera and Render Setting - Color Mapping (simple adjustment of light and color interaction)

Sun
http://www.spot3d.com/vray/help/150R1/vraysun_sky_param.htm
http://www.spot3d.com/vray/help/150R1/examples_vraysun_sky.htm

Color Mapping
http://www.spot3d.com/vray/help/150R1/render_params_colormapping.htm
http://www.spot3d.com/vray/help/150R1/examples_colormapping.htm

Camera
http://www.spot3d.com/vray/help/150R1/vrayphysicalcamera_params.htm
http://www.spot3d.com/vray/help/150R1/examples_vrayphysicalcamera.htm

Here is topic on forum about color of the sun
http://forum.vrayforc4d.com/viewtopic.php?t=171

cheers
Tong.

[MrBraun]

Take a look here! :)

http://www.forum.vrayforc4d.com/viewtopic.php?t=258

[GIOLETS]

Hi to all, this is my first post...
I'm starting to make my first steps in vray world...

So, I've read also this interesting question about the search of a calibrated scene for testing materials and I've considered that as my start point for my experience.
So (I'm novice therefore excuse for mistakes..) I've create a simple exterior scene, having:
- a physical sun at the default values of 3/0.35/2/0.05 placed at an height of 400 cm (simulating a morning sun)
- a physical cam with a common setup for a snapshot in the real life (in an exterior enviroment): f4 1/125 ISO 100
- an initial color mapping setup of 1/1/1
- Physical sky enabled
my intention is to see if the overall quantity of light is believable respect to an equivalent exterior scene in the real life.

The only adjustment that we should do would be then the Color mapping parameters, for my opinion (to be honest I've read vlado documentation on it at: http://www.spot3d.com/vray/help/150R1/vraysun_sky_param.htm#references).
So, no touch the Sun multiplier, no adjustments on the phy camera settings.. it's a correct way to proceed for your opinion?
In that way I've obtained a little bit under exposure with the default parameters mentioned above, and a correct exposure twiking a little the Color mapping parameter to D 4 B 3 Gamma 0,8.

Need to have your feedback...

[Tong]

better see one time ;-)

place file please to rapidshare or send it to gantonr@gmail.com

[GIOLETS]

Thanks Tong, here the link:
http://rapidshare.com/files/72916871/Exterior_standard_setup.rar.html

not more complicated scene: just the standard setup I think.

Let me know your suggestions.

[stefan]

" a physical sun at the default values of 3/0.35/2/0.05 placed at an height of 400 cm (simulating a morning sun) "

if you use the official version 1.08 the standard value for sun is 1 not 0.05.
please update to newsest version, thast 1.08

cheers
stefan

[stefan]

the best light to text material is a neutral light situation, no hard shadows no colored lights or enviroment, etc.

the lightsetup and camera muts be that if you input a colorvalue that the rendering has the same colorvalue in the main parts(at least roughly)

the object must show round, flat, cylindrical surfaces, round and sharp corners, thin and thick parts for tranlucent objects.

thats all
cheers
stefan

p.s. such an object scene will be available for free on the vrayforc4d material repository when it opens

[Tong]

GIOLETS now you can download this scenes for material tests:

http://www.computergrafica3d.com/utenti/mrbraun/Test_scene.zip
http://www.learning4d.it/video/TOOLS4Dmtl.zip
http://rapidshare.com/files/71231851/Natural_Weave.zip

http://www.computergrafica3d.com/utenti/mrbraun/Chrome.jpg