Independent lens maker Sigma has unveiled two new fisheye lenses exclusively designed for digital SLR cameras with an APS-C-size imaging sensor.

Designed to deliver a 180° angle of view, the 4.5mm f/2.8 EX DC HSM Circular Fisheye boasts a minimum focusing distance of 13.5cm and maximum magnification of 1:4.6.

Special Low Dispersion Glass aims to help reduce chromatic aberration while the Super Multi-Layer coating aims to minimise flare and ghosting.

?This lens is ideal for photographers using computer stitching software which requires circular fisheye images to be input,? said a spokesman for Sigma Imaging UK.

Also unveiled is the Sigma 10mm f/2.8 EX DC HSM Diagonal Fisheye, which is designed to produce ?striking images with exaggerated perspective and distortion?, according to company. The Nikon-fit version delivers a 180° viewing angle (154° for Sigma and 167° for the Canon-fit version).

Both lenses allow full-time manual focus override using the focus ring and include a Hyper Sonic Motor (HSM) for ?fast and quiet autofocusing?.

Both optics will be available in Sigma AF, Canon AF and Nikon AF mounts.

UK prices had yet to be announced at the time of writing.

For details call Sigma Imaging UK Ltd on 01707 329 999.

Sigma 10mm f/2.8 EX DC HSM Diagonal FisheyeSigma 4.5mm f/2.8 EX DC HSM Circular Fisheye