Lens Sharpness by Ken Rockwell

Sharpness is the most overrated aspect of lens performance.

Lens sharpness seems like it ought to be related to making sharp photos, but it isn't.

continue reading at:

http://www.kenrockwell.com/tech/lens-sharpness.htm

For Cancer theraphy

VLC: open-source multimedia framework, player and server

"It plays everything!"
The media player that fills all your needs. It can handle DVDs, (S)VCDs, Audio CDs, web streams, TV cards and much more.

http://www.videolan.org/vlc/