PDA

View Full Version : Black objects in render.



DCjr
08-26-2015, 01:28 PM
Im going nuts trying to figure out how my instanced objects are turning out black in my renders.

Any ideas? Just doing a basic monte carlo render - everything was fine until I saved out the object with a different name because I made some changes to it. I even ended up clearing out my instancing and reapplying it.

Any help would be appreciated.

Oldcode
08-26-2015, 01:54 PM
Go to the Surface editor for each object. When you select a surface, look for "Diffusion" If diffusion is set to 0%, increase it to 25%, 50%, 100% etc, and see what happens.

Good Luck,

Sensei
08-26-2015, 06:43 PM
Show screen-shots (forum allows attaching pictures).

When there is issue (any kind), you should start turning off option by option, and rerendering, to see whether one of them is causing issue.

Do you have f.e. 1,2-point polygons in your mesh.. ?
They can show as black spheres/black lines, if there is Render Lines turned on in Render Globals.

There is needed more info, better with screen-shots or attach whole scene showing issue.

DCjr
08-28-2015, 10:54 AM
Show screen-shots (forum allows attaching pictures).

When there is issue (any kind), you should start turning off option by option, and rerendering, to see whether one of them is causing issue.

Do you have f.e. 1,2-point polygons in your mesh.. ?
They can show as black spheres/black lines, if there is Render Lines turned on in Render Globals.

There is needed more info, better with screen-shots or attach whole scene showing issue.

Hi
I got it to go away for awhile but it came back. I spent hours working with this trying to figure it out. At one point I thought my instanced object was being shadowed by another object - because an instanced object needs to be loaded into the scene an it sits at 0,0,0. Which is below my rolling hills ground plain. My instancing is a random generic generation with no weight maps for distribution. just basic. Oh and I turned off cache for my render for this new test session.

So I did a limited frame render 3 times that I put into one image. The render on top shows the original camera position. You can see the dark grass. Not all of the grass is dark though.

So I pulled the camera back and out and that is the middle render.

I rendered a third time, this time pulling the camera way back and up and the dark grass disappears!

129524

DCjr
08-28-2015, 11:17 AM
So I turned off the grass, and created a new simple instance of a tall box, grass size. I also turned off radiosity. (Turning off radiosity didn't work for the grass) but I just kept it off in this render.

129525

boxes look ok. No problem. Maybe something with my grass object. I applied SSS to the grass. maybe that is the problem. I will check

Adding a new render.

Turned off SSS on grass and now grass renders ok!

129526

So it looks like maybe a bug in SSS.

Bummer. Hope it goes away on my next render test!

mummyman
08-28-2015, 11:40 AM
I don't think SSS works with instanced objects.