With the new Fisheye filter much of what the Lens Correction filter is made easier with hardware specific presets.
One issue where the lens correction filter might be used over the fisheye is for warping the edges of a video using keyframes.
The fisheye filter does not have keyframe capability at this moment where the lens correction filter allowed for more control over transitions of one scene blending into the next.
Example: To replicate one scene being laid on top of the previous a mix of Opacity, Size, and Lens Correction allows for the incoming scenes edges to lay flat over the previous scene at a different speed than the center of the scene. (Similar to how a piece of paper might fold in a U shape before landing on a surface and flattening out)
Keeping the Lens Correction filter even as a legacy filter while moving forward with the Fisheye (similar to the Sepia Filter) would allow for interpolation with the Fisheye while being able to use the Lens Correction for distortion/warping of the z axis.
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