Compositor backdrop won't show the current composite result

Hey folks. Working through the Match Track Blend DVD and hitting every stupid branch on the way down.

I’m just about finished with the Two Point Track video (, only with some depressingly crappy luminance masking. I was trying to fix this when I realised that the Compositor backdrop was only showing the video footage, not the combined image (as seen in the image/render port, bottom left).

Does anybody know what I should be doing here? I should point out that I’m using Cycles instead of the Blender Internal (as in the video sequence) - as I’m trying to migrate most of my skills from Internal.

Many thanks in advance,


(On the left, my current setup. On the right, a clip from the Match Track Blend tutorial)

Yeah Blender’s VSE default output is black if there is no active strip available to render. You could just stick a scene strip in there, but I try to keep VSE and compositor scenes separate as there can be issues with performance.

That is if you have complex 3D or compositing as well as a VSE in one scene, then the VSE will become sluggish as it won’t ignore all the other stuff.