How compatible are Sigma Lenses with Canon's in-camera lens correction?

Q:  How compatible are Sigma lenses with Canon's in camera lens correction?

A:  This function must be switched off when using Sigma lenses on Canon cameras - otherwise digital circles and shading will appear in both live view and the final image. 

Please see the below advisory from Sigma - which while specific for the Canon EOS 5D mkIV - is relevant for all Canon DSLR's with lens corrections (Vignetting and chromatic aberration).  The advisory for the manual adjustment of AF is specific to the 5D mk IV.

Sigma Releases 5D Mark IV Incompatibility Warning

Thank you for purchasing and using our products.

Please find the following notes on the usage of SIGMA interchangeable lenses for EOS, when attached to Canon EOS 5D Mark IV that is released on September 8th.

  • MO (Manual Override) function is unavailable with this camera (Full-time Manual function can be offered).
  • When using a SIGMA interchangeable lens for EOS, setting the corrections to [Disable] is recommended, as “Lens Correction” functions of the camera, such as Peripheral illumination correction, Chromatic aberration correction, Diffraction correction and Distortion correction are not supported.*

* If those functions are activated, the performance of lenses may not be accurate. 
* This is not only for EOS 5D Mark IV, but also for other camera bodies with the same function.

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