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 50mm f/1.4 EX DG HSM is the first large-aperture 50mm prime lens to be manufactured by Sigma and the company has gone to considerable lengths to include the latest designs and technology.

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

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.

Similar in size, features, and price (though not format) to Sigma's 30mm f/1.4 high-speed "normal" prime for DSLRs with APS-C sensors, this 50mm full-framer ($500, street) also belongs to Sigma's EX family of pro-quality glass.

This is the first Sigma 50mm f/1.4 prime lens for 4/3 DSLRs, a tele photo lens in the focal length of 100mm equivalent to portrait lens in medium distance. A superb lens of optical quality and design, fast focus in silent with HSM.

Fast aperature in f/1.4 with beautiful bokeh; Short lens barrel and well balance of weight by hand-held with camera body; Fast focus speed in silent with HSM

I also have the 30mm 1.4 Sigma and I just love these 2 lenses they behave similarly but the 50mm Is probably sharper. Obviously I use the 50 as an 80mm small tele on DX format Nikons. I am a regular newegg customer but I did not buy this lens from newegg, I should have...

Very well built, SUPER SHARP, fast AF (HSM), perfectly balanced on D300; It is soo much better than the Nikkor 50mm 1.4 that I traded the Nikkor away; The Bokeh` is (to me) Gorgeous, so just run and get this gem!!

NONE; well OK perhaps didn't need to be a 77mm filter tread..

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.

What a whopper! Sigma's 50mm f/1.4 is twice the size and weight of other similar lenses and has a colossal front element promising superior peripheral brightness (reduced corner shading) and improved contrast at wider lens apertures. The finish and the controls are rock-solid.

Let me start by explaining my score of 4 on image quality. If I had the option I would give it a 4.8 rather than a perfect 5. When the aperture is wide open at f/1.4 images get 'creamy all over'. But with the right light this effect can be absolutely stunning!

Bokeh; Focus Speed; Sharpness

77mm filters