Hmmm f4 lens are not that fast to make any differenece to the frame rate !! To get at the Raw file compression files of Canon Nikon cameras you need a util called DCRAW a free sourcecode file you can find here   http://www.cybercom.net/%7Edcoffin/dcraw/ Most of the major players also decrypt the metadata whatever the above link is an interesting read for those who want to contribute something worthwhile to the thread.. You may find it interesting  Thanks to those who have..

Danny O'Byrne  http://www.digitalartzone.co.uk/

"All the technique in the world doesn't compensate for the inability to notice" Eliott Erwitt