The pictures below illustrate the angles of view on 35mm full frame and APS-C (1.6x crop) camera bodies. Our observations indicate that the focal length is noticeably shorter than the specified 50mm (probably closer to 47mm):

Class-leading image quality; Relatively low vignetting even at wide apertures on full frame; Reasonably fast and positive autofocus; with full-time manual override; Very good build quality

Large and heavy for a 50mm F1.4; Expensive

This high-specification Sigma prime comes with a price-tag to match, but does image quality meausure up? Read the WDC Sigma 50mm f/1.4 EX DG HSM review to find out

Imposing presence

Distinctly heavy

Gary Wolstenholme takes a look Sigma's first f/1.4 aperture standard lens, which sports a silent HSM focusing motor.

Excellent sharpness in the centre at most apertures; Low vignetting; 77mm filter size is the same as most professional level zooms

Maybe a little softer than I'd hoped at f/1.4; Heavier than any other 50mm f1.4 lens; Bigger than any other 50mm f/1.4 lens

It is hard not to be drawn to a fast prime - the short, fat, solid-feeling lens with very low-light capability is very attractive. So, I don't find it surprising that the Sigma 50mm f/1.4 EX DG HSM Lens has received a lot of attention in the early days of its availability.

Although zoom lenses are certainly versatile and convenient, they do have some drawbacks, including relatively small maximum apertures. A typical 28-90mm equivalent zoom may provide an aperture of f/3.5 at short focal lengths but it will be f/5.6-6.3 at longer zoom settings.

The new Sigma AF 50mm f/1.4 EX DG HSM is a refreshing alternative in the long-ignored standard AF lens market. The lens is fairly big and heavy due to unusually big glass elements but thanks to the design efforts it is already capable of delivering sharp images straight from f/1.4 and the resolution...

Gary Wolstenholme takes a look at this fast f/1.4 aperture standard lens suitable for full frame and crop sensor DSLRs.

Excellent sharpness in the centre at most apertures; Low vignetting; 77mm

Maybe a little softer than I'd hoped at f/1.4; Heavier than any other 50mm f1.4 lens; Bigger than any other 50mm f/1.4 lens

good value, best 50th i have seen, good useable for studio and on location, you need a little time to focus, thearefore in use, when aperature must be wider than f4

great bokeh; sharp from f 1.4 onwards; good contrast; no problems wirth autofocus accuracy; speed similar to good macros

CA wide open; focus ring does not work smooth

Performance & handling Prime lenses are about as simple as can be in terms of handling. You have just two controls – the focus ring and (depending on your lens mount) the AF/MF switch.

The contrast between the sharp and the blurred is often overlooked by still photographers as a creative tool, but it's often used very effectively by cinematographers.