light reflection problem

[Buck]

Hello, in an effort to create a "white card" with a gradient on it, I created a VRay material with the diffuse color set to white, and "output" in the map slot, output cranked to +4. I then put a gradient ramp in the transparency map slot and tweaked it till it gave a good gradient to compensate for the +4 output of the diffuse.

Anyway, when I viewed the reflections (in the ball, in this simple test) the reflections whent from a nice hot white to a black as soon as I have the white card behind the camera or the camera moves around the camera (as in this example GIF)

I took out the gradient transparency and the problem is still there. Here is a gif of what I mean, and the max file to go with it. Does anyone know whats going on here? Or does anyone know a better way to make a white card with a gradient on it? It has to have output of more then 1 in order to give hot highlights.





http://www.danielbuck.net/wip/vray_help.zip


Thanks for your help!

[vlado]

You need to use a VRayLightMtl for the white card, or the Self-illumination slot in a standard material.

The diffuse color/map is not the right way of doing this, as it will only multiply the light falling on the surface, but will not make the surface emit light itself.

Best regards,
Vlado

[Buck]

is there any way to use a gradient in the light material, so that the light fades off to transparent? I tried with the light material, but did not have any success in making it a gradient falling off to transparent.

[vlado]

is there any way to use a gradient in the light material, so that the light fades off to transparent? I tried with the light material, but did not have any success in making it a gradient falling off to transparent.

In that case, it would be best to use a Standard material with the diffuse color set to black, and an output map in the self-illumination slot. That way you can control the transparency too.

Best regards,
Vlado

[Buck]

I see no change when I do that. I get a nice gradient, but when I view from the other side the white card turn black for some reason. Normally, I would have the white card not visible to camera, when I do that I get the same result, a black reflection instead of white.







www.danielbuck.net/wip/vray_help2.zip

this is very strange, is it not? I hope there is a way around this. Thanks Vlado!

[winberg]

Crank up the self illumination spinner to 100%..
That should fix your problems..

-Tom

[Buck]

ah, that seems to do it! Thanks so much!