video files and black backrounds when you dont want them?

deadly_serious · Post by **deadly_serious** » Sat Feb 12, 2005 5:50 am

G'day mate from Australia. I am using moho version 5 and I have a big problem with rendering vidio files with any backround colour other than black. Even when you set the backround colour to white or red etc it always makes the backround black. This makes using particle effects and other effects very limited. Do you have any suggestions?

jorgy · Post by **jorgy** » Sat Feb 12, 2005 6:33 am

I'm a newbie here myself, but I think what you need to do is create a rectangle of your desired color and put it behind your particle layer. I think what's happening is the background color is coming up as the alpha layer in your avi.

If this is wrong, someone please correct me.

Post by **Lost Marble** » Sat Feb 12, 2005 7:21 pm

Are you using the "Do not premultiply alpha channel" option when rendering? That would make the background black, but it shouldn't matter - if you don't want the alpha premultiplied, that means you want to use the alpha channel later, so ultimately the background won't appear in the final composite.

If that's not the issue, then we need more information. You shouldn't have to create a background rectangle - the background color should appear in the final output. What video format are you using (AVI or QuickTime?), and which compression codec? Also, if you can post an example file, that might help figure it out.