Sigma Warns of Focus Issues Using Its Lenses & MC-11 Mount Converter on Sony a9

For customers using SONY a9 (ILCE-9) camera

Thank you for purchasing and using our products.

We have found that the combination of SIGMA MOUNT CONVERTER MC-11 (SA-E and EF-E) and some of SIGMA's interchangeable zoom lenses may not focus precisely, if it is attached to SONY a9 (ILCE-9), released by SONY in May in 2017. When using AF-S mode and shooting in telephoto range, it could occasionally display the shot is in focus, although it may not properly be focused on the subject.

We apologize for the inconvenience experienced by customers who use these products. We are now investigating the phenomenon and will make a further announcement on the website shortly.

We appreciate your continued support for our company.

For further information, please contact your nearest authorized SIGMA subsidiary / distributor.
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