Temporal AA smearing

Hi, I’ve got a mesh which I’m moving across a background plane but the temporal aa is leaving a smeary after image during the movement. My camera isn’t moving. Is there a way to tell a material or object to not affect the temporal aa?

If I used the console command node to reduce then increase the r.postprocessaaa setting as the animation started would this be likely to cause a crash?

Alternatively are there any settings I can tweak to reduce this ghosting effect without switching to fxaa?

I’m using 4.9.2.


Do you use “accurate motion vectors” flag for that object?