In focus

£5,899/$6,599

This high-end fast telezoom is an upgrade to a much-loved lens, but it is worth the extra money? Andy Westlake takes an in-depth look

Totally exasperated about telephoto extenders? Bothered by battery life? Send your technique and camera questions to digitalcamera@futurenet.com

Why don’t we use round image sensors to capture the full image circle, asks Jon Devo

£190/$199

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