Reducing flickering artefacts.

I've made a little 3D video which can be seen here

Rendered in Modo, I then imported the frames into  Hitfilm. 

There are artefacts around the edges of objects which makes it twinkle. This is just a side effect of how it renders, it's slightly differently each frame. I wonder if there's a way of reducing it in Hitfilm?  It's not really film noise or grain.


  • Triem23Triem23 Moderator

    Doesn't Modo have Anti-Aliasing? That should fix the issue at Modi's end.

    In Hitfilm you'd be making a duplicate of the footage, putting that footage into its own comp, adding Find Edges, then a Hue Saturation Lightness filter and turning saturation to 0, then Curves to punch the whites a little higher. After that you'd bring this into your main comp and hide it, create a Grade Layer on top, add a 1 pixel Blur, then a Set Matte effect, selecting your edges comp as Source  Layer , a Luminance  matte type and a Replace blend mode to limit the blur to the edges. This probably softens edges you wanted to leave crisp. 

  • To me that looks like something to do with your render settings dealing with reflections and/or shadows.   I've never used Modo, though, so I'm afraid I don't know where to tell you to look for a solution.  If you haven't already done so, I would post this to some Modo forums/groups and get feedback from folks with more experience in that software.

  •  Thanks Triem, that is the sort of thing I was looking for. I've tried what you suggested but it hasn't really worked very well. I'll keep experimenting though.

    Yes I can fix it in Modo but it dramatically increases the render time. When you're rendering hundreds of frames for an animation it quickly adds up. I'm just curious to see if there's a way to speed things up using Hitfilm's tools.

  • There may be a way, but I'm always a bigger fan of fixing the source than fixing it in post.

  • Triem23Triem23 Moderator

    So. 3D renders usually need anti aliasing, which is basically tossing blur on object edges.

    Anti aliasing obviously slows down a render.

    BUT letting Modo antialias is still best solution. MODO can correctly calculate edges and blur just what needs blur. Any attempt to blur in post... Well, I can't think of a better method than I already suggested--Find Edges and blur. Antialias is basically an edge blur.. 

    But, really just let Modo antialias. There's the old "Quality Triangle" joke: Good, Fast, Cheap--pick two. Modo antialiasing is good and cheap. Fixing in post is cheap and fast. You're better sacrificing fast for good. 


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