Canon 50mm F1.4 USM EF Lens - Description:
The Canon 50mm f1.4 is standard lens featuring superb quality and portability. 50mm f1.4 lens has got two high-refraction lens elements and Gaussian optics eliminate astigmatism and suppress astigmatic difference. Canon 50mm F1.4 Lens gives crisp images with little flare are obtained even at the maximum aperture. 50mm f1.4 is useful in low light conditions in photography. Canon 50 mm F1.4 Lens is a bit heavier than the 50/1.8 but it gives you simultaneous AF/MF because of Canon 50mm F-1.4 Lens USM focusing motor. 50mm f1.4 lens is one f-stop slower than the 50/1.0 in the Canon's lenses but much lighter weight and less than one-sixth the price.

If you are going to limit yourself to one 50mm prime lens, then the Canon 50mm f1.4 is the natural choice. 50mm f1.4 is reasonably light in weight, a joy to focus manually or automatically, the Canon 50mm f1.4 lens has an 8-blade diaphragm so that out-of-focus highlights look natural. Canon 50mm F1.4 Lens has a bayonet lens hood. If you're stuck with Canon EOS bodies, it won't cheer you to know that Popular Photography's comparison of Canon 50mm F1.4 EF USM lenses showed the Contax/Zeiss 50/1.4 to be slightly better than Canon's. On the other hand, the Canon lens proved superior to Leica, Minolta, Nikon, and Pentax (in that order). is a widely used lens.

The Canon 50mm f/1.4 USM lens Specifications:

Focal Length is 50mm
Maximum Aperture of is 1:1.4
Construction is 7 elEFents in 6 groups
Diagonal Angle of View is 46º
Focus Adjustment (Overall linear extension systEF with USM)
Closest Focusing Distance is 0.45m / 1.5 ft.
Filter Size of is 58mm
Max. Diameter x Length : 2.9" x 2.0", 10.2 oz. / 73.8 x 50.5mm,
Weight without packages is 290g

The Canon 50mm F1.4 lens is compatible with all Canon film and digital SLR camera

The Canon 50mm f/1.4 USM lens included accessories:

Canon front & back caps.
Canon 50mm f1.4 lens instruction manual.