Sharpness (center and borders), focal range, weight, construction. A good lens for
A7/A7r.

Only 20-35mm

I use this lens with a Sony A7r. Picture quality is extremely nice. The lens is not too heavy and delivers
sharp images up to the borders, when stopped down.

Similar Products Used:

Sony Zeiss 24-70mm

Quality of Construction
Quality of Images
Versitility
Smoothness of Zoom and Focus
Replaces four prime lenses

Loss of 1 f stop from prime lenses.

This is my second FD 20-35mm f3.5L lens. I purchased it as a back up for my original (you never know) which I purchased3new in 1982 to replace three prime lenses. The quality of my photos was not decreased by switching to this lens and taking my 20, 24, and 28mm f2.8 lenses out of the bag. Several years ago, just for my own information I shot a roll of controled comparison photos and the results were that I could not discern any degradition by using the zoom lens.

My international travel bag now contains 2 - A1 bodies, a set of zooms; 20-35 f3.5 L, 35-105 f3.5-4.5 Macro, 80-200 f4 L, and my only prime lens 300 f2.8 L, and a 577G Flash. Plus the normal filters, cleanning supplies etc. The only change I would make would be to get an 80-200 L zoom if only Canon had made one.