Copied from this thread. http://www.newschoolers.com/ns/forums/readthread/thread_id/559087/page/2/
Good post on Cinema5d.
"Lots of great primes to try, many work with a tight budget.
I shoot mostly alternate glass, and still do even with the new firmware. I've sold all of my canon lenses but two, because the alt glass is superior for video and stills.
This is my first post here on Cinema5D, so i'll share some juicy secrets:
Here's my short list:
Pentax SMC 20mm f4 Great lens, incredibly small. Good luck finding one, but if you do ! $300
Olympus OM Zuiko 28mm f3.5 Not super fast, but super small and incredibly sharp. Sharper than the Canon and better tonal range $50-$80
Carl Zeiss 28mm f2.8 distagon A legendary 28mm, but i prefer my zuiko 28mm $300
Carl Zeiss Jena Flektagon 35mm f2.4 Insanely sharp, incredible lack of distortion, fantastic close focusing. Absolutely killer. $100-200
Pentax Super-Takumar 50mm f1.4 Some versions have thorium radioactive glass (not harmful) and it's an incredibly dreamy lens. One of my favorites, ever. $40 !
Pentax SMC 50mm f1.4 Many say it's better than the legendary Zeiss and i agree. Amazing contrast, punch. Far better than the canon 50mm f1.4, and only $100-$150 You need to modify the lens a little to not hit the mirror. Easy 5 mins.
Contax Carl Zeiss 35-70mm f3.4 As good or better than every Canon L prime within it's range. Better than the primes ! Killer macro mode too. Must have lens. $350
Minolta Rokkor 58mm f1.2 The legend. You need to hack the back or get a custom mount, but woah, f1.4 and SHARP WIDE OPEN. Arguably better than the $4500 Noct-Nikkor. I got mine for $250, but i hear the price is running up these days
Leica R 90mm f2 Summicron This thing is like two lenses in one. Wide open it's sharp but beautifully dreamy and 3D - great for headshots (a bit like the Pentax Super-Takumar 50mm f1.4 radioactive). Stopped down it's razor sharp. Leica lenses have this wonderful way they 'draw' and the results have this '3d' look to them. Some clients have specifically asked for the '3d' lens. $300 There's an APO corrected version which is blazing sharp wide open, much more expensive, and not as good for portraits.
So no.. You don't have to shoot Nikon. There's a lot better alternate lenses than Nikon, and they're cheap. All of these lenses work on your 5D with the right adapter, available on ebay for $20-$45 each. Many have focus confirm chips so they 'beep' when in focus.
Build an entire rig for half the price (or less) of a Canon L lens.
The killer price / performance setup:
Olympus OM Zuiko 28mm f3.5 $50-$80 It's not just good for the price, it's good for ANY price. This lens is sick
Pentax SMC 50mm f1.4 $100-$150 Fast, razor sharp, near as good as a 50mm gets. Period.
Canon 85mm f1.8 $300-$400 Yep, not an alternate... This thing should be called an L lens. They're incredible, cheap, fast and way-overlooked.
World-class quality with a wide, standard and semi telephoto for only $500-$600ish wow
I've got around 23 alt lenses, done numerous shootouts, obsessed over reviews and tech specs. You can get really great stuff cheap, if you don't mind manual focus (great) and manual aperture (great)
Good luck. There's a whole world of amazing (and dirt cheap) lenses which work on the dreamy 5D"