Elevations and windows.

[Marcos.Geraldo]

Rendering glass perpendicular will not come out right. I cant figure it out. Any advice will be helpful. I am using a camera and the sky for my light source. the glass on the right comes out overexposed with the clear glass material. So i make the object very opaque and now you see the back wall very grainy. the windows on the left are sunken in and are dark. I dropped a rectangle but nothing. What should i do, i could tweek the model, shall i tilt the glass? what the easiest way render glass.

this one i cant figure out
https://docs.google.com/leaf?id=0B8K...ZDg2YjFm&hl=en

This other elevation looks a little better
https://docs.google.com/leaf?id=0B8K...ZjZjNmE3&hl=en

Also my image always comes out muddy. how can i solve this, which setting will be the easiest to adjust? sun, camera?

[40th]

Re: Elevations and windows.

I can't see the images

[Marcos.Geraldo]

Re: Elevations and windows.

1. http://img708.imageshack.us/img708/7...eationwest.jpg

2. http://img36.imageshack.us/img36/786...levtouchup.jpg


This should be better.

[40th]

Re: Elevations and windows.

The glass will look more realistic if it had something to reflect (like in real world there's environment reflected in glass)
Check this tutorial http://forum.asgvis.com/index.php?topic=4942.0

[Marcos.Geraldo]

Re: Elevations and windows.

Thank you for the response and the tutorial.

[Marcos.Geraldo]

Re: Elevations and windows.

I followed the tutorial. I planned to use trees on the back ground and they were going to reflect of the glass. But it does not work. I am doing an Elevation so my focal view is set at 1. When ever I place the image, it moves?! The image always wants to be in my view. I wish I could get it to work. I cant excluded some how from my view? Or can I do a double material and see right through it while it projects on the glass?

-Marcos

[dcauldwell_cg]

Re: Elevations and windows.

With a long focal length (or narrow field of view!) your camera will always end up behind the billboard and will thus obscure the model.
The way I would do it is to put a HDRI (or jpg) background in the 'environment-background' slot - this can be rotated to suit.

David

[Marcos.Geraldo]

Re: Elevations and windows.

I will give it a try, thanks for your reply.

[dcauldwell_cg]

Re: Elevations and windows.

Oops - I got it wrong.
My way doesn't work either - sorry Marcos. I could have sworn that I'd done it that way.
Not sure what to suggest now.

David

[Marcos.Geraldo]

Re: Elevations and windows.

Yea I couldn't figure it out, I was messing with the background and placing an image, but I couldn't get it to work. Solution, Photoshop! You guys advise me its the reflection is what sales it, so I dropped an image on the glass, cropped it, used luminosity and decrease opacity. I used to drop just a plane blue background, but this works better. It starts to look more like glass. If I could figure out how to add a gloss to the glass in photoshop I hit the jack pot. To be furthered explored....

the detail:
http://img197.imageshack.us/img197/7...nuploading.jpg

Over all, difficult to see:
http://img210.imageshack.us/img210/7...nuploading.jpg

[40th]

Re: Elevations and windows.

It's also a workaround. Often I use ps to add reflections, because in some arch. scenes it's faster and easier way.

[**dubs**]

Re: Elevations and windows.

. . . Also don't forget, refractions and any translucency/fog only take place on a 'thickness' of material. . .

I have ran into this in the past. . .

If your glass is modeled as a single surface for simplicity then I would recomend post processing in Photoshop or similar, because Vray just doesn't have enough to work with!

If you would like to have Vray produce better results, the glass needs to have a thickness, you could take the single surface you have (?) and under the solid menu in Rhino Extrude Surface. . . give it a realistic thinknes in whatever units you are using. . . it wouldn't take long at all

In the glass material setting, set your IOR (Index of Refraction) to 1.55 (glass) and render the scene again. . .

With a single surface only reflection, diffuse colour and transparency can be seen in the result

By making a solid object you have 2 reflections, diffuse colour, transparency, and refraction/translucency and fog colour. . . it gives a lot more options in the properties of the material!

(in the materials library on the ASGvis download section, ALL of the glass you see in the previews, is applied to a 'watertight' solid object. . . with a single surface you won't see anywhere near the same result!)

Hope this helps !

Cheers

Stu

[dcauldwell_cg]

Re: Elevations and windows.

Stu

Sorry mate, but I beg to differ. I think for simple external shots, like the one shown, simple single plane glass works just fine.
A while back I did some tests with different glass settings
http://forum.asgvis.com/index.php?Itemid=90&topic=2234.
and I'm sure that the tut by Teofas does the same.
It all in the settings!

David

[**dubs**]

Re: Elevations and windows.

You don't have to be sorry David! Different strokes for different folks

I was only offering a suggestion that I know has worked for me in the past.

Your tests look really interesting, I understand you're using the single surface approach in those tests . . .

I don't have huge experience with external shots, but I would imagine the Vray sun is bleaching out the glass with its brightness?

In your tests David, you had an interior behind the glass, in this case it looks like the glass is lit almost equally well on both sides, even its background is external.

With that in mind, another approach for the problem above could be to lower the Transparency of the diffuse layer in increments of 20, until something more glass-like appears? I'm guessing this might already have been tried. The reflection is hugely important (as already stated) but there are obviously other things contributing to its lack of visability.

If what I suggested earlier was a bit more scientific, I'd consider this more of a 'trick the eye' approach.

From a professional point of view, whatever achieves the desired result quickest, is best. No?

Regs

Stu

[**dubs**]

Re: Elevations and windows.

Whoops, I've got the wrong end of the stick here

I was reading the glass as being right upto the edge of the canopy. . . its not, is it? ???

David is right ignore me, I miss read the context of what was being asked pretty badly!