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Kitchen Renovation
Posted: Fri Mar 07, 2008 8:25 pm
by jvanmetre
Sharing a render from a recently renovated kitchen...1920's center hall colonial...moulding around windows is typical of the era...countertop represents a granite (verde agave) surface...
Noticed the appearance of what I think are caustics -- likely due to large number of surface reflections? SL is about 18.
Hope to improve on the control of the hdr in the background, it looks a little flat.
jvm
Posted: Fri Mar 07, 2008 11:27 pm
by Bubbaloo
Looks pretty real.
You've definately got a caustics problem.
Are you using real glass in the windows or ags?
Do you have any light fixtures with glass lenses?
Posted: Fri Mar 07, 2008 11:40 pm
by jvanmetre
Brian-
Thanks for the feedback...really need to add the strawberry jam to the knife and the crumbs from the toast to the countertop to bring it to full reality -- at least for my house.
I just dropped in a lowgradeglass.mxm -- for the windows and glasses, also using a "bulb" form in the lightbulb emitter in three overhead fixtures. Bulbs sit inside a reflective diffuser (it looks like a typical pendant lighting fixture).
jvm
Posted: Sat Mar 08, 2008 3:09 am
by Bubbaloo
I wouldn't use low grade glass for the windows, and especially for the light bulbs. Really, unless you can actually see the bulbs in your render, you don't even need them. Just use an emitter plane inside your light fixture. This will speed up your render bigtime and eliminate those caustic spots.
Posted: Sat Mar 08, 2008 3:29 am
by jvanmetre
Brian-
Thanks again, agree on using an emitter plane for bulbs not visible. Is there something better than the low grade glass for windows?
jvm
Posted: Sat Mar 08, 2008 3:59 pm
by Bubbaloo
AGS for windows. It has no render-slowing, caustics-creating refraction, and for windows, this is perfect. You will have to adjust the reflectance to your liking.
Posted: Sun Mar 09, 2008 5:51 pm
by jvanmetre
Thanks...will give it a go...
jvm
Posted: Mon Mar 10, 2008 7:10 pm
by jvanmetre
Brian-
I switched the glass to ags...still getting the white dots. I next tried removing the lamp shades covering the overhead lights with no change.
Is it possible to have too many reflective and transparent surfaces?
jvm
Posted: Mon Mar 10, 2008 7:14 pm
by Bubbaloo
Hmmm...
Are you using hdri for any illumination? Sometimes I get dots when doing that. What are you using for your environment lighting?
Posted: Mon Mar 10, 2008 8:35 pm
by jvanmetre
Brian,
Yes, I'm using the hdri for illumination...thought I was using it as well for environment lighting?
jvm
Posted: Mon Mar 10, 2008 10:32 pm
by Fernando Tella
I think your problem might be coming from a way too shiny material. The trouble could be due to a unnaturally shiny layer which have some bump also (which spreads the caustics) and is set to additive mode.
A coating could be causing it too.
Check first the materials near the emitters.
Posted: Fri Mar 14, 2008 12:58 pm
by Tim Ellis
Could be the old random extra bright pixel in the hdri map.
Open the hdri in HDRShop and equalize it, then resave it.
Tom posted this method in reply to a render with the same spots.
Also using RS:0 (preview engine) can produce these spots too.
What's the material setup for the green cupboards?
eidt:- Also are the downlighters, that can be seen in the window reflection, shining through a glass lens? Remove the lens if so, and that will help.
Tim.