The SX520 HS is expected to land on the UK high street in August, costing £299.
Its ‘high-sensitivity’, back-illuminated imaging sensor boasts a maximum ISO sensitivity of 3200.
However, the SX400 IS (£259) will not go on sale until January 2015, when it will be sold exclusively through Argos stores.
Both cameras carry a Digic 4+ image processor and a redesigned grip, to offer ‘comfortable, DSLR-style ergonomics’.
The lens on the PowerShot SX520 HS is designed to deliver the 35mm viewing angle equivalent of a 24-1,008mm zoom, while the SX400 IS’s lens carries a 24-720mm equivalent focal length.