Sigma SA lenses on A7/R through adapter
Not all Sigma SA mount lenses are for crop-sensor cameras. The Sigma 35mm DG lens is for full-frame, not just APS-C sensor cameras. Sigma lenses with the "DC" designation are for APS-C sensor cameras and will result in vignetting on a full-frame camera but is it's not a DC lens, it won't vignette on a full-frame sensor camera.
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