My clip with alpha channel is getting a shadow

DataMeister wrote on 8/31/2007, 6:09 PM
I have composited a few digital juice clips to make a lower third. I can drop a video clip on the timeline below these clips and it makes a perfect overlay. However when I trie to render out the lower third without a background and then overlay in another project the lower third gets a faint black outline or shadow.

I rendered to an uncompressed Quicktime file.

Is there a trick to rendering with alpha channels that I don't know about? Why would I be getting this dark area around my new rendered overlay when used in new projects?

Comparison

The above image is a partial screen grab from Vegas of both overlays. The top half is the original overlay composite. The bottom half is the rendered overlay demonstrated the newly aquired shadow or whatever.

Aside from the obvious shadow below the overlay, you can also see on the counter top, right side, above the overlay, the top example shows a light green highlight surrounding the red peppers and the lower example shows a darkened area surrounding those peppers.

So, how do I render the lower third so that it doesn't gain a shadow or whatever is happening? Any ideas?


Comments

farss wrote on 8/31/2007, 7:28 PM
I've had much the same problem with V7 and alpha channel handling. Raised it as an issue here but no real answers.
Perhaps V8 will fix this.

Bob.
Jim H wrote on 8/31/2007, 7:54 PM
are you applying any effects to that event? Perhaps it is a render order issue... you know, those little triangles of death if you get them out of order?
DataMeister wrote on 8/31/2007, 8:31 PM
There are no effects on the events. However there is a 3D blinds transition that brings the main bar into the frame. There are also some track motion changes to position events properly on each other.

I am not familiar with the triangles of death however. How do those work?