What seems a little odd to me is that in the first chapter of the announcement Sigma specifies this is an issue with the new Canon EOS 5D Mark IV.
But when you read the full announcement, they are also saying you could face the same issues with other Canon camera bodies as well. Here’s the full announcement Sigma released.
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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