diff --git a/Compare-Videos.ps1 b/Compare-Videos.ps1
index 28accb6..6ca3c7b 100644
--- a/Compare-Videos.ps1
+++ b/Compare-Videos.ps1
@@ -576,7 +576,7 @@ if (-not $NoAudio) {
 
 $ffmpegArgs += @(
     "-c:v", "libx264",
-    "-preset", "fast",
+    "-preset", "slow",
     "-crf", "8",
     "-pix_fmt", "yuv420p"
 )
diff --git a/Stich-InBetween.ps1 b/Stich-InBetween.ps1
index ece3df2..e421d43 100644
--- a/Stich-InBetween.ps1
+++ b/Stich-InBetween.ps1
@@ -250,7 +250,7 @@ if ($PSCmdlet.ShouldProcess($TempDir, "Generate interpolated frames with rife-nc
 
 if ($PSCmdlet.ShouldProcess($Video, 'Create output video with ffmpeg')) {
     Write-Host "Executing ffmpeg (FPS=$FPS)..."
-    & ffmpeg -y -framerate $FPS -i "${TempDir}%08d.png" -crf 8 -c:v libx264 -pix_fmt yuv420p "$Video"
+    & ffmpeg -y -framerate $FPS -i "${TempDir}%08d.png" -crf 8 -preset slow -c:v libx264 -pix_fmt yuv420p "$Video"
 
     if ($LASTEXITCODE -ne 0) {
         throw "ffmpeg failed with exit code $LASTEXITCODE"