Quote Originally Posted by realityinabox
I mean both quantity and quality. Good isolation of the subject, as well as smooth blurring of the background.

Here are a few I could find in a quick search, both shot at f4:


50D with 70-200 f4L @ 100mm - f4 - 1/250 - iso-100 - subject-distance 1.4m(according to exif)





50D with 70-200 f4L @ 70mm - f4 - 1/1600 - iso-400 - subject-distance 7m(according to exif)





Both images are uncropped, so original dimensions.


Also take a look at Pixel-Peeper and use their advance search option.


Good luck, Jan