Linear workflow

[cristoforo]

In the middle of a project and decided to try out the linear workflow.....though it seems to be washing out the image....especially the sky. I followed the tutorial in the TIPS section. What do you think? In addition, should more light be entering through the windows? This seems to be a common problem. How do I go about getting more light to enter?

[cpnichols]

The light through the windows thing may be an issue with light not penetrating the glass. Sorry, this may be a stupid question, but did you make sure and check the effect alpha on the glass?

[cristoforo]

NOt a stupid question....no it was not checked. Checking now to see if it makes a difference. I have GENERATE GI off on the glass. Is this correct....I remember reading that it speeds things up. I never get good reflections using vray material for glass. In the end, I ususal have to use a standard material with vray map in the reflection slot. Still struggling with this! No.....affect alpha made no difference.

[Da_elf]

he might have meant affect shadow

[cristoforo]

affect shadow is checked

[oconv]

well, there was a discussion about sunlight through glass in the radiance list some time ago. here is what Greg Ward said:

I think the challenge to rendering the interior of a building through
a glass facade is exactly the same trouble you would have
photographing it -- the reflections will tend to overwhelm the
interior unless there is direct sun penetrating the space, something
architects try to avoid. Typically, an interior is less than 10% as
bright as the exterior during daylight conditions, and this is
(roughly) the amount of light reflected by standard glass.
Therefore, the reflections are intermixing with the light from the
interior, and it's difficult to see any details that aren't confused.

Things are made better if you can get just blue sky or something
without detail in the reflection, or use a polarizing filter and
shoot near the Brewster angle, where all the reflected light is of a
particular polarization. This would be a nice trick that Radiance
(unfortunately) cannot do properly, as it lacks polarization in its
simulation. (Well, we had to cut back somewhere...)

physical explanation of a daily phenoma

[TRGraphics]

Does your glass have a thickness, even 1/8" is enough. If not, you need to have it for glass to work properly.

Tony

[flipside]

You should not turn off send GI if you want GI to go trough the glass. If you want light inside the building, simply put lights inside them. The main problem is as greg ward described, just fake it by adding lights inside.

Try to look out of the window at night when it is light in your room, impossible because of the big difference in lighting. Same is trough in your scene, only you are oustside and the outside is lighter than the inside now.

[cristoforo]

Thanks for the help! I'll give it a shot now!

[olitech]

Another thing you might want to try if 'affect shadows' isn't enough...is to right click on all your glass and under max properties untick 'cast shadows'...brute force, but you know....

[momentum]

What we do a lot to get light inside a building is just to exclude the glass from the light. So that the light ignores the glass and passes right through it with full force. You still get reflections and secondary bounces on the glass. As long as the glass shadow colour is not an issue it works well.

[g.ross]

You may also want to make your glass really transparent. Something like an RGB of 253,253,253 in the Refract. g

[timmatron]

And in the glass properties, uncheck receive and cast shadows.

[DaForce]

Also if your worried about the sky being washed out ..wrap it in a color correct map and set gamma to 2.2. (you may need to download color correct if you dont have it already)
That should fix it for you.

[paulison]

i've been ticking "reflect on back side" for my glass these days and i think it helps a lot

Precalc lighting with glass turned off, then render frames with glass on. This works well for animations as you probably will do a precalc anyway

But if you are lazy like me, put some lights inside. Some people use vray plane lghts on the glass but i usually just chuck a few sphere lights in the rooms