vray lighting problem

[Cesar]

Hello to everyone

 

I hope someone can help me with this problem.

I´m doing an image about an interior office, it´s in the earlier esteps, just light checking. My idea its to make a very iluminated space. In my first tries i got the ambient that i wanted, but when i put some glass divisions, the light changes very drastically, i don´t know why because its a very clear glass, totally transparent.

I put my settings if someone wants to check it.

the render engine its VRay 1.46.15 and the software it´s 3Dmax 7, i put the settings of the rendering method.

There is an image with a plan view to show the lights position, all the lights are vray light, i also put the lights settings, all are the same. I use a normal direct light for the sun.

I put the material settings for the glass division.

 

Thanks for your help.

An sorry about my english

[Cesar]

This is the image without the glass interior division, thats the ambient light that i wanted.

[Cesar]

and this is what happened when i put the glass division, both image has exactly the same settings, in render, lights and materials.

I dont know if there is a problem with the glass material, i tried with to many diferent settings, but i always had the same result.

In both images i use irradiance map for the first bounce and light caghe for the second, but the funny thing its i have the same problem using photom map, and even irradiance map for the first and quasimontecarlo for the second.

I know that its normal that the ambient light change when i start to put diferent elements, but this change its very strong, i think this is not normal.

look how the background change from white to grey, there also is a door in the left part of the image, this door doesnt have any glass in front, just next to this door are a wood division with a glass division in front, the door and the wood division has the same material, but look how strong the glass changes the material of the wood division, and remenber that the glass its totally transparent, very strange.

[Cesar]

this its another try, in this case i change the material of the glass division from vraymatl to an standar 3ds material, and only reduce the opacity to 5.

In this case the ambient light reduces, but in a more natural way, more realistic i think, but with this material i can get reflections, and vray doesnt work well with max raytraced materials.

[kippu]

did you try calculating the irr map without the glass and then putting the glass material in it and just rendering with the old irr map?

[Tim Nelson]

On your Vray glass material, make sure the "affect shadows" option is turned on. That will let the light pass through it.

[Cesar]

Hi, thanks for your replies.

Tim if you check the the material setting you will see the affect shadows and alpha are checked, so i dont know what is wrong.

Maria, i alredy tried your idea, the ambient light gets little better, but not the best, and i still have problems with objects near to transparent divisions, i put an image with light cache for first and second bounce, and a second image with irradiance for the first bounce, and for the second i use the light cahe solution for the first image.

Note in the first image (only light cache) the background is white but the reflection in the floor is grey, is this normal?

[Gabriella_A]

Hallo Cesar...

 

I remeber that I read somewere that to let the light pass correclty trough glass wall you had to check (in the GI -Indirect illumination- general settings) the GI caustics to reflect and refract, doesn't matter if you don't check caustics on in the caustics tab.

 

I remember that in the past I was having problems similar than yours... after I read that , I always check the caustic relfect/refract and never had problems with light trough glass anymore.

 

Hope it helps...

 

Gabriella

[Cesar]

wow Gabriella, you´re totally right, i change this settings and everything starts to work very well, sometimes the answer it´s so simple that you can´t see it.

 

I put some images, i think the diference is very obvious.

 

thanks Gabriella

[grcarvalho]

"this its another try, in this case i change the material of the glass division from vraymatl to an standar 3ds material, and only reduce the opacity to 5.

In this case the ambient light reduces, but in a more natural way, more realistic i think, but with this material i can get reflections, and vray doesnt work well with max raytraced materials."

 

I know that this is a very old topic, but i was searching for a solution for the glass on vray 1.5 and them i found this message, and as i know that tons of people read this becouse of google, i would like to say that you can have reflections on regular max standard materials.

 

Just let the opacity in 25, then go to maps, adjust the reflections to 20, and click on the NONE and change it to vraymap.

 

if you turn on refraction, even if your glass is plane, it will increase what is behind it, so, just do not turn it on...

[pg1]

I also get results by selecting the glass and going to vray properties and unticking the visible to GI box.

You can also untick the generate and recieve GI boxes as glass being transparent wont affect you bounced colour.

 

Alternatively you could increase how much GI it generates and I think it would increase the amount of indirect light in the room (haven't tested that idea)

 

also try selecting the glass and in properties (not vray properties) untick cast shadows.