Frame Edge Shading
"Frame Edge Shading" is darkening along the edges or in the corners of the frame due to camera hoods or production flags being partially in frame.
Frame edge shading impacts the Content Quality of the asset. Customer experience is negatively impacted by anything that might obscure visual content. This can also be a revealing visual cue to the filmmaking process, removing the suspension of disbelief. This may be creative intent to create a more "film-like" experience or may also be creative “vignetting” implemented during color correction to add depth to an otherwise “flatly” lit scene.
Noticeable darkening along the edges or vignetting in the corners of frame.
How to Prevent:
Check edges of frame while shooting, and adjust any camera hoods/ production flags, so that they do not encroach on the edge of frame.
Using a radial graduated neutral density (GND) filter can help when the source of darkening is natural vignetting.
Review and confirm if this is creative intent. Otherwise, scale the image or apply a VFX fix to conceal the shading.