Lens review
2009-06-16
Sigma 50 mm f/1.4 EX DG HSM
10. Autofocus
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This category happens to be a Sigma’s Achilles heel. Even lenses equipped with an USM motor, especially while working on a Canon, give unsatisfying effects. The biggest was our pleasure when we found out that the Sigma 1.4/50 HSM is difficult to fault here. The autofocus motor works very quietly and quickly, going through the whole scale in about 0.5 second. The error number was moderate – 8% in the studio conditions. It can certainly increase in worse conditions.
The tested specimen had a slight frontfocus tendency but it appeared only if wide open, becoming practically imperceptible by f/2.0
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