transparency for vray glass?

[huntch3]

hi everyone

a friend of mine made a glass material for me, but im having trouble making it more transparent...do you know how i can keep all the attributes the same, but change the transparency level? Ive attached a pic of my settings and an example of my glass that im trying to make more transparent....thanks for any input!

[Stephen Thomas]

Darken the diffuse colour or lighten the refraction colour.

[nige777]

Hi,

 

Just noticed that 'affect alpha' is not checked under the refraction roll out - if you want light to shine through it you need this option checked, but yes I also agree that you could do with lightening the refraction colour to something closer to white.

[huntch3]

i see, Ill try that thanks....do you think I should have the the fresnel reflections checked? Ive tried this and I think it makes the glass look too transparent. Also, what about checking caustics on??? would this be better? thanks for your help again!

[erickdt]

Hi,

 

Just noticed that 'affect alpha' is not checked under the refraction roll out - if you want light to shine through it you need this option checked, but yes I also agree that you could do with lightening the refraction colour to something closer to white.

 

This is not the case. You simply need to have "affect shadows" checked. Affect Alpha is only to have the objects transparency shown in the alpha channel.

 

As to the original post of this topic: you can make the glass material more transparent by making the refract color closer to white. Absolute white is 100% transparent, absolute black is 100% opaque.

[nige777]

This is not the case. You simply need to have "affect shadows" checked. Affect Alpha is only to have the objects transparency shown in the alpha channel.

- Doh sorry! My mistake, trying to do 1000 things at once and not fully concentrating on what I was doing - however it looks like 'affect shadows' was not checked either.

[clubber2k]

I've had some problems with transparency too..

 

I've noticed that adding an opacity map (white) really makes things clear!

I'm guessing this wasn't the way I was meant to do it but I would like to know more. what is the opacity maps job in the vray mat maps?

 

thanks

[3dwannab]

I've had some problems with transparency too..

 

I've noticed that adding an opacity map (white) really makes things clear!

I'm guessing this wasn't the way I was meant to do it but I would like to know more. what is the opacity maps job in the vray mat maps?

 

thanks

 

Attached are two maps,

 

1st one is simply a jpg

2nd another jpeg (this time with a black area and white area)

 

here is a way to use the opacity channel

 

you can use the 1st map in the diffuse and the 2nd map in the opacity slot.

 

This way the the black areas on the second map don't render and the white areas allow the diffuse colour to come through. allowing you to place a tree in the scene with just using maps on a plane.

 

There are other ways to do this but this is the easiest to understand what the opacity channel does. e.g using just 1 .tiff file with an alpha channel in it.

[clubber2k]

not excatly what I meant. transparency is controlled via the refract panel right?

well I noticed I cant get the glass as clear as I want.. even with refract at 100/75/50/25% and diffuse at same values of gray.. its always a bit opaque.. like a dust dirty window

 

I have to say I used a tilemap to make a curtain wall btw. when I took the tilemap into the opacity and set the window to full on white - then I finally got a good CLEAN glass.

it the mat window the mat looks like a black disinegrating circule which makes me think thats not the way I was ment to use it, but it works in the render it self.

 

can you creat a clean transperant glass only with diffuce and refract? and what did I do when I set an opacity to it? I opacitated the refracration?

[alias_marks]

seems like things are getting a bit confusing. I'd recommend giving this a read to help clarify some things a bit. Aversis does a great job with making things simple.

 

http://www.aversis.be/tutorials/vray/vray_basic_material_settings_02.htm

[Stephen Thomas]

Haha! That is so weird, I was just in the middle of posting the exact same link as I figured it was quicker than trying to explain everything myself. Great minds, eh?

[alias_marks]

haha! quite right stef hehe. hope all is well

[3dwannab]

not excatly what I meant. transparency is controlled via the refract panel right?

well I noticed I cant get the glass as clear as I want.. even with refract at 100/75/50/25% and diffuse at same values of gray.. its always a bit opaque.. like a dust dirty window

 

I have to say I used a tilemap to make a curtain wall btw. when I took the tilemap into the opacity and set the window to full on white - then I finally got a good CLEAN glass.

it the mat window the mat looks like a black disinegrating circule which makes me think thats not the way I was ment to use it, but it works in the render it self.

 

can you creat a clean transperant glass only with diffuce and refract? and what did I do when I set an opacity to it? I opacitated the refracration?

 

 

Here is a .mat file downloaded form http://www.vray-materials.de (free once registered to download the materials) Worth a look

 

unzip it and you can see once you load the material into the material editor how it was made.

 

You don't use an opacity map to make clear glass. Only for the example I explained to you as you asked what it does.

[clubber2k]

seems like things are getting a bit confusing. I'd recommend giving this a read to help clarify some things a bit. Aversis does a great job with making things simple.

 

http://www.aversis.be/tutorials/vray/vray_basic_material_settings_02.htm

 

ohh I remember seening this, thanks

 

and I used a few glasses from vraymatde but weren't clear enough! (clean freack! )

 

anyway.. thanks for the input and effort!

[Stephen Thomas]

The problem you are having is that if you have a light colour in the diffuse slot then the glass will never be clear. Your diffuse should be black and any colour in the glass should come from either the refraction slot or the fog value.

 

Also you should not be using Opacity/transparency for glass, this does not give you a realistic look and is a very 'standard material' method. Refraction using a reasonably proper IOR will give your material depth and thickness as well as correctly affecting what you see through it. As shown in the link Mike gave you the standard setup for vray glass is black diffuse, white reflection with fresnel checked and white refraction slot, remembering to check the affect color/shadows/alpha box as applicable. I also like to add a greenish tint to the refraction slot which not only colours the glass slightly, especially if the edges of the glass are visible, but also tints the shadows cast by the glass in a nice way too.

 

So my standard architectural glass material is as above but under refraction I would have H:100, S:5, L:240. You need to lower the luminance slightly from full white to allow it to pick up the colour and cast a very slight shadow, as real glass would.

[Stephen Thomas]

I should also qualify this by saying that getting material settings from someone else or from vray-materials.de or wherever is no substitute for being able to create your own and having a good understanding of what the different parameters do, as you have discovered.

 

I very rarely use preset materials and usually create them on a per-project basis. It only takes a few minutes and besides, presets will always need tweaking in relation to your scene/lighting anyway.

 

Look through the tutorials on the aversis site as well as the vray help files where the parameters will be explained in detail then experiment yourself.