Matchmoving and Compositing in Blender 2.8 Eevee

by Louis January 4, 2019

Thought I’d try out some match-moving and compositing with Blender 2.8 beta with Eevee. I’m used to using Boujou and After Effects and wanted to see how it compares.

I headed out to capture some footage as well as a 360 environment map. I captured the footage at 14mm and 40mm (35mm equiv) but found only the 40mm footage to be usable, mainly due to sensor stabilisation causing odd distortions. I’m questioning whether to use sensor stabilisation at all as it likely causes issues with match-moving due to the optical centre of the lens shifting during capture.

While feature tracking, I found issue with motion blur, having shot the footage at 1/50. I had some success with using larger pattern sizes, which resulted in much more uniform curves. I created one forward and one backward feature track with only auto detected trackers, adjusting the threshold to 0.001, distance to 80 and margin to 60 on 1920×1080 footage, allowing for trackers to spread more evenly over the frame. I’m trying to mimic how I’d match-move a scene in Boujou, which in many cases is a 1 click affair.

After solving the camera, with the refine focal length option enabled,  I appended a mech I’d previously created as well as setting up the environment texture from the 360 capture, which I colour corrected to be closer to the captured background plate. I captured the 360 environment with the ‘theta’ cameras 8 bit HDR mode to capture the most dynamic range possible then added a curves node and increased the strength value to balance out the response curve.

I tried to get a shadow catcher working, using Schillem’s method. Which did technically work but showed the environment behind the transparency and not the background plate. I also tried using the background plate on a poly locked to the camera but found Eevee doesn’t play nice with image sequences yet. In the end I create 2 view layers, one with all elements (including a white floor as a shadow catcher) and one with just the mech.

With the render taking all of 6 seconds I jumped into the compositing tab and combined all the elements, multiplying the shadow layer over the background plate, adding the mech layer over and sprinkling some post effects to tie everything together.

I’m reasonably happy with the result and saved a lot of time by not alternating between multiple programs, as well as time saved rendering out the CG at 6 seconds a frame on a laptop. However, I find I’m able to get much better match-moving results in Boujou with very little effort. However, this may be due to my lack of experience with Blender’s tracking.