How to get good and correct window reflections

[Jon Berntsen]

Hi!

 

I think I need some advices on how to get better window reflections.

They tend to get flat and unrealistic. This is not an issue just happening with this single scene, but every one of them.

 

Here you see the typical case. Left is original photo (the good feeling) and right is the render (the bad feeling).

 

[ATTACH=CONFIG]41620[/ATTACH][ATTACH=CONFIG]41619[/ATTACH]

 

 

Facs about my scene:

 

- No lights inside of the building

- VraySun

- An image in the environment map (for background)

- GI environment override

- Reflection override with a hdri map

- Window planes has been given a depth

- VrayPhysicalCamera

- LWF

- The window material is this one: http://www.vray-materials.de/all_materials.php?mat=2060. When taken into max, its name is Glass Window Perfect.

 

Other usual scene setups would be plain vraysun and sky, I was just testing some HDR for this particular scene.

 

Here are some of the believed most important settings:

[ATTACH=CONFIG]41621[/ATTACH][ATTACH=CONFIG]41624[/ATTACH][ATTACH=CONFIG]41622[/ATTACH]

 

 

Any suggestions? I would be very grateful for any tip!

[sanmb]

Increase reflection.

Make window material more bright.

Make environment map bright and render image.

Try adjusting these till you get good result.

[sanmb]

GI override unclick path.

[Jon Berntsen]

Hi thanks for your replies Sanjay. If I increase the reflection any more, the room inside is gone.

I will try playing with the window material brightness, also the env map.

 

What do you mean with unclick path? Appreaciate your help!

[sanmb]

GI environment and reflection refraction,

On left side you can see ON if you click it turns on if u unclick its off,on the right side beside path(after none) it should be off for GI environment,for reflection refraction its on which is fine.

March 2nd, 2011 03:54 AM window4.jpg

(5 of 5)

[Jon Berntsen]

I just got some nice improvements, I didn't turn the brightness on the diffuse on glass up, but actually down to black.

[ATTACH=CONFIG]41625[/ATTACH]

 

I still feel that I'm still missing some of the highlights of the sky, and some darkness in the reflected object (tree). It like it's missing some contrast. If I turn up the reflection further, it only gets too bright again. I know I can play with all the parameters, but I don't know exactly where to start.

[Jon Berntsen]

Right. Thanks. Never noticed that one to the right.

[sanmb]

see this

[sanmb]

Good Luck.

[notamondayfan]

it could be how the tree in the reflection is being lit. if its being lit from behind, then you are going to get a better sillouette, and probably more light inside the room too. From your render it looks like the tree is being lit from the side, so its quite illuminated, probably simularly to the front of your building, so you lose the sillouetting. If you cant achieve it in Max, just play with your refraction pass, a good S curve will probably sort this out.

Dean

[Jon Berntsen]

Thank you. Yes, how the reflected object is being lit (by the sun) is also a factor I didn't count in. You are correct, the sun comes in more from the side than from behind on this one.

 

However, I managed to improve it. I changed the diffuse color on the glass to black, and cranked up the overall for the reflection hdri. That seems to work on this particular project, but it generally makes me loose control on the reflections other places in the scene...

 

[ATTACH=CONFIG]41640[/ATTACH]

 

 

It should also be mentioned that I added a light inside to get some more depth.

Edited March 2, 2011 by chroma