I searched for my EOS 550D a small sharp "always on it" when things do not (yet bulky) Tamron VC should be 17-50. Application: Street, Photo walks general and street portraits. When I unpacked it, I was just convinced the feel to the touch. By contrast, my EF 50mm 1.8 II feels like a cheap plastic cups. The AF is relatively quiet and is almost always his goal. The focus is the strength of the new 40s: even at maximum aperture is at least as good as the above at Tamron 40mm, Fade Out only has too little out of focus growth in 40s (while the Tamron is even better then). The bokeh gets smooth, no ghosting or similar .. In short, one can confidently use open, without having to think great what aperture you drive straight. Simply screw it and have fun. The only getting used to at this glass is the manual focus: even if the switch is set to M and is then focused, this is done on the engine. This makes itself noticeable with a buzz. I am not a professional, but a dedicated amateur photographer who chooses his equipment carefully. So I had the 35mm 2.0 back back because I had to stop down to 2.8 in order to achieve sharp results. The still considerably cheaper 40 mE is the more modern and sharpness lens. At crop cameras it is for "normal lens" with a slight slope toward the telephoto (64mm equiv.).
