I am new to FM. I have been wondering for a while now about my next lens purchase so figured I would ask here and see what peoples views are.
I shoot Video on a Canon 60D. I already have, the nifty fifty, 135L & 10-22mm Lenses. I have a shoulder rig follow focus and tripod. I feel like I want to either go with a fast and wide lens, bit on the other hand I have been thinking about a zoom :s i'm thinking either, Canon 35mm 1.4 L, Canon 24-70MK1 (they seem to be going cheap with the announcement of the MK2). For a cheaper option, maybe the 30mm 1.4 Sigma?
For video i would chek for samyang/Rokinon etc... They have excelent IQ and for less than 1/3 of the price of your two contenders. Of course you would have to use primes but i personnaly dont like zooms in video. Off course if you shoot live action and you need a zoom to make shure you always frame everything than consider the 24-70MM 2.8L wich is indeed a good lens.Keep in mind that those samyang/Rokinon dont have autofocus so if you consider still shooting it might be a little more tricky to use.
The favorites of Samyang/Rokinon are the 14mm 2.8 35mm 1.4 and the 85mm 1.4 They both have proven their self as great lens with excelent IQ and built Quality.They also have a 24mm 1.4 that is supposed to be good but i never tried it.
For video, I'd definitely go with a zoom, and the 24-70 is very nice and relatively fast. It is not as sharp as the Mark II, but given video resolution I don't think that will be noticeable. I don't shoot video, but that zoom will fill a gap for you and give you zoom in the video.
The 24-105 would also be an alternative for you and fill more of a gap, though it is a stop slower. One or the other will have a better "feel" for video zooming and that probably should be the deciding factor.
The 24-70L has good manual focusing and is used by a lot of videographers on the 7D since its good and very versatile. The 35L however is better optically and mechanically, it is outstanding. Its a more substantial lens than the 50. The 24L is also a great choice.