Sigma 50-100mm f/1.8 DC HS M | A £950/$1,100
A uttle something for DX Cameras
This is the only lens in the test group that’s actually designed exclusively for DXformat cameras, on which it gives an ‘effective’ zoom range of 75-150mm. Despite the relatively small image circle required by APS-C format sensors, and the downsized zoom range, it’s still about the same size and weight as most 70-200mm f/2.8 lenses, and has an oversized 82mm filter attachment thread. This is due to its main claim to fame: its super-fast f/1.8 constant aperture.
The lens’ relatively short focal length range and extrawide aperture are more beneficial to creative photography with tight depths of field, making the Sigma more desirable for portraiture and still life capture rather than action sports and wildlife photography.
One of Sigma’s Art rather than Sport lenses, it retains a ring-type ultrasonic autofocus system but AF speed is relatively slow, and there’s no optical stabilizer.