Canon lenses have absolutely no relation to Leica lenses. There is no comparison. With all due respect Tina, that's rubbish f0.95 Canon f0.95 Leica = same DoF Aside from that mathematical fact, I was comparing lens focal lengths, formats, DoF's and CoCs not brands (you have heard the story that Leica purchased and had rebadged under contract a Sigma zoom lens?) And push come to shove and gloating over lenses - I sit here with not one but two a 40-400 : 5.6 Taylor Hobson Thorium Element lenses .. this company won a technical oscar for their zooms - you can hire them for cine (with much higher technical requirements than still photography) for a little over $500 per day from panavision http://www.panavision.co.nz/Main/printrent.asp?cat=all - mine are for still work. so no, I don't just use Canons. I also use Angenieux's as well as Tokinas and Industars - whichever lens is best for the job Did I mention my Bausch and Lomb 500mm TELE? karl
