The cause is that the ImportFBXProperty in MovieSceneToolHelpers.cpp is divided by DecimalRate.

ArriveTangent = ArriveTangent / ((Key.Time - PrevKey.Time) * DecimalRate);
LeaveTangent = LeaveTangent / ((NextKey.Time - Key.Time) * DecimalRate);

But, this calculation is also done in  FMatineeImportTools :: SetOrAddKey,

NewKey.Tangent.ArriveTangent = ArriveTangent / FrameRate.AsDecimal();
NewKey.Tangent.LeaveTangent = LeaveTangent / FrameRate.AsDecimal();

so there is no need to divide in ImportFBXProperty.

Probably the cause of this issue is that CL-4443201 does not consider ImportFBXProperty.

export data

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import data

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Steps to Reproduce
  1. Open attached project
  2. Open Level Sequence Asset in Contents
  3. Export FBX Animation of Cine Camera Actor of the Level Sequence
  4. Import the exported FBX to the Level Sequence (toggle off match by name only)

expect : The curve of the Cine Camera Actor is completely reproduced

result : The Tangent value of the Cine Camera curve (Current Focal Length in the example) is different.

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ComponentUE - Anim - Sequencer
Affects Versions4.26
Target Fix4.27.1
Fix Commit17249264
Main Commit17249264
Release Commit17279402
CreatedAug 20, 2021
ResolvedAug 20, 2021
UpdatedDec 1, 2022
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