raytrace reflection on screen artefacts & movie render Queue


this is a two part thing…

first my spec…
4.25 official release [haven’t updated yet]
RTX 2080 ti
latest studio drivers

part1. can’t understand why these raytrace reflection computation artefacts don’t ever resolve [if it is in fact what they are?]. Even if I up the samples per pixel under raytrace reflections from my default of 4 to the max 64 the artefact is still present [only from 4 to 64 the rate and which the flicker occurs decreases]. this flickering seems to happen [or be more apparent anyhow] more in low light conditions.

also, I can only stop the flickering by clicking outside of ue4. if i return the mouse to ue4 again it returns with a vengeance…

what is this?

this takes me to point 2. > Movie render Queue

in an attempt to up the quality and see if its just a screen based artefact I try using this newish tool to output a few frames…
still the problem persists…even with upping the spatial sample count to 64 for Temporal AA and None… again from its default value to 64 samples there seems no difference.

as a aside note, i tried using FXAA and no matter how hard i try i cannot get my frames to output…it goes through the process and outputs nothing…why?

cheers for any help on these two points

rtx flickering here as short video:


I have the same flickering problem. And cannot find a way to solve this either… (Render Issue with 4.25 - Rendering - Unreal Engine Forums)

So with the flickering raytrace artefacts it looks like we are looking at a potential bug in 4.25…

Can the same be said for my Movie Render issues?
Anyone had a similar experience or know what I/is going wrong re the sampling and anti aliasing methods here?

Out of curiosity are you using Final Gather for GI?

Upping the sample count usually improves reflections for me but I find that final gather always fills the scene with noise in low light settings.

hi, no not using gi as I have no sky/sun system… just a studio type shot with a number of local (mobile) point and rect lights.

So not a ‘rays per sample’ thing…

Thank you though!