Unreal Engine TAA Changed In 4.28+? How To Get Old Version Back

Development Rendering
1

Was the default TAA changed in later versions of UE4 and/or in UE5? Here are the TAA values I was using on UE4.27 for my Ultra preset, that look bad/different UE4.28 & UE5+

r.TemporalAA.HistoryScreenpercentage=200
r.TemporalAACurrentFrameWeight=0.25
r.TemporalAA.Mobile.UseCompute=1
r.TemporalAA.R11G11B10History=1
r.TemporalAA.UseMobileConfig=1
r.TemporalAAFilterSize=0.09
r.TemporalAAPauseCorrect=1
r.TemporalAA.Upsampling=1
r.TemporalAACatmullRom=0
r.TemporalAA.Algorithm=0
r.TemporalAA.Quality=2
r.TemporalAASamples=2
r.BasePassForceOutputsVelocity=1
r.VelocityOutputPass=1

Using these same commands in newer versions or any build of UE5 produces DRASTICALLY different results. If Epic has changed the default TAA, I have two requests/questions

1 - What’s the best way to approximate the old TAA so I can get it back? Is there any CVARs I’m not utilizing

2 - Would you consider adding a similar command back to UE5.5 or something that changes TAA to match its older values like r.TemporalAA.Algorithm? The new TAA has some big benefits, but its not a 1:1 upgrade, the older version produces better results for what I’m aiming for.

2

UE5 produces DRASTICALLY different results

Such as? I’ll go ahead and guess more flicker right?

UE4’s subpixel pattern is different when r.TemporalAA.Upsampling=1 and r.TemporalAASamples=2

You’ll have to builds and modify UE5 from source.

You’ll probably have similar results in UE5 using these commands instead:

r.TemporalAA.Quality 2 (0 is more crisp, but more ghosting)
r.TemporalAACurrentFrameWeight .6 (with vsync)
r.TemporalAASamples 2
r.TemporalAAFilterSize 0.09
r.TemporalAA.Upsampling 0
r.TemporalAA.R11G11B10History 1
r.TemporalAA.HistoryScreenPercentage 100
r.TemporalAACatmullRom 0

3

Thanks for the help. Although it doesn’t look similar at all to my commands on UE4.27, any version higher than that the anti-aliasing looks different with identical commands.

To explain how it looks different, I feel like motion blur is worse for one. Using these commands on my project, motion blur in pretty minimal whereas on UE5 its very noticable, which results in me having to use higher values, which results in more jitter and less effective anti-aliasing.

I have 3 versions of my project -

4.27: Anti-aliasing is effective and clear in motion at native 1440p

4.28: Anti-aliasing looks more noisy (because its not as effective at hiding the aliasing at these values) and when moving the camera or character their’s severe blur noticeable, blur not previously present.

5.4: Same issue as 4.28

The test demo has trees, foliage, some objects, and a road. I’m not happy with the results at all