Compared to...

This review is part of a series looking at a number of 50mm primes, including those which we use for the test shots in our camera reviews. We're also taking the opportunity to compare the brand new Sigma 50mm F1.4 EX DG HSM with those older 50mm F1.4s, to see if the benefits of modern computer-aided lens design and manufacturing techniques translate to a tangible improvement in image quality.

Side by side

Below you can see four fast standard primes side by side; from left to right (and largest to smallest), the Sigma 50mm F1.4 EX DG HSM, Canon EF 50mm F1.4 USM, Nikon AF-Nikkor 50mm F1.4 D, and the Pentax smc FA 50mm F1.4 (the other currently available equivalent, the Sony 50mm F1.4, is practically identical in dimensions to the Nikon). The Nikon is a pretty compact lens, especially in comparison to the Sigma, and little larger than the manual focus version upon which it is based. Indeed its design reflects the long heritage of the F mount; it incorporates a traditional aperture ring, which makes it as usable on old manual-focus 35mm SLRs as on modern all-electronic DSLRs, and it uses the camera body's built-in AF motor, which means it won't autofocus on the D40, D40x or D60 (although manual focus and autoexposure still work just fine on these cameras).

Specifications compared

	Sigma 50mm F1.4 EX DG HSM	Canon EF 50mm F1.4 USM	Nikon AF-Nikkor 50mm F1.4 D	Pentax smc FA 50mm F1.4
Street price	$500	$325	$290	$200
Maximum format size	35mm full frame	35mm full frame	35mm full frame	35mm full frame
Focal length	50mm	50mm	50mm	50mm
35mm equivalent focal length (APS-C)	• 75mm (1.5x) • 80mm (1.6x) • 85mm (1.7x)	80mm	75mm	75mm
Diagonal Angle of view (FF)	47º	47º	47º	47º
Diagonal Angle of view (APS-C)	>31º	31º	31º	31º
Maximum aperture	F1.4	F1.4	F1.4	F1.4
Minimum aperture	F16	F22	F16	F22
Lens Construction	• 8 elements/6 groups • 1 aspherical element	• 7 elements/6 groups	• 7 elements/6 groups	• 7 elements/6 groups
Number of diaphragm blades	9, rounded	8	7	8
Minimum focus	0.45m	0.45m	0.45m	0.45m
Maximum magnification	0.14x	0.15x	0.15x	0.15x
AF motor type	• Ring-type ultrasonic • Full-time manual focus	• Micro-type ultrasonic • Full-time manual focus	• 'Screw drive' from camera body	• 'Screw drive' from camera body
Focus method	Unit, internal to barrel	Unit	Unit	Unit
Image stabilization	• None	• None	• None	• None
Filter thread	• 77mm • Does not rotate on focus	• 58mm • Does not rotate on focus	• 52mm • Does not rotate on focus	• 49mm • Does not rotate on focus
Supplied accessories	• Front and rear caps • Hood • Soft Case	• Front and rear caps	• Front and rear caps	• Front and rear caps
Weight	505 g (17.8 oz)	290g (10.2 oz)	230g (8.1 oz)	220g (7.8 oz)
Dimensions	84.5mm diameter x 68.2mm length (3.3 x 2.7 in)	73.8mm diameter x 50.5mm length (2.9 x 2.0 in)	64.5mm diameter x 42.5mm length (2.5 x 1.7 in)	63.5mm diameter x 38mm length (2.5 x 1.5 in)
Lens Mount	Canon, Nikon, Pentax, Sigma, Sony	Canon EF only	Nikon F only	Pentax K only