If using the Legacy renderer (Movie Scene Capture) with DefaultRHI DirectX12, there's new delay and also some frames get weird artifacts.   However, the delay and artifacts do not appear when using DirectX11.

I've attached two PNG examples with artifacts, one is correct, rendered with DirectX11; another one is wrong, rendered with DirectX12: "LegacyDirectX11.png" "LegacyDirectX12.png" 

This is repeatable in UE 5.1.1, UE 5.2 and UE 5.3 ( //UE5/MainTest )

Below is a link to the example project where this issue can be reproduced:

[Link Removed]


Steps to Reproduce
  1. Download and unzip the example project listed in the description
  2. Open the project.   The "/Game/DisableBuffer" Level should already be loaded.   Open the "/Game/RenderSequence" Level Sequence in Sequencer.
  3. Verify the RHI is set to DirectX12 in the project settings.
  4. From Sequencer, click on the three dots next to the Render Icon ( clapper icon ) and select the Movie Scene Capture (Legacy) option.
  5. Click on the Render Icon again to open up the Movie Scene Capture panel.  Change the Image Output Format to "PNG".  Select "Capture Movie"
    1. The first few frames will either be black ( delay ), or rendering artifacts near the top and bottom of frame.
    2. Repeat the render process a few times to see how the delay and behavior changes on the first few frames, however the first few frames will always are either black or have artifacts on them.
  6. Change the project's RHI to DirectX11 in the project settings.  Restart the project when requested.
  7. Repeat the rendering process with the Movie Scene Capture using DirectX11.
    1. This time there will not be artifacts on the first few frames.   They look correct.

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ComponentUE - Rendering Architecture - RHI
Affects Versions5.
Target Fix5.4
Fix Commit27146511
Main Commit27146511
CreatedJun 19, 2023
ResolvedAug 16, 2023
UpdatedNov 20, 2023