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BGtom
Oct-24-2009, 07:58 PM
Does anyone know if any of canons EF/EF-S lenses have non-electronic focus rings? Meaning, the focus rings DO NOT spin endlessly? I presume this would mean the lens is non-AF. I ask because it would be nice to have a lens an assistant could reliably pull focus on when shooting video.

Thanks

Richard
Oct-25-2009, 01:44 AM
Does anyone know if any of canons EF/EF-S lenses have non-electronic focus rings? Meaning, the focus rings DO NOT spin endlessly? I presume this would mean the lens is non-AF. I ask because it would be nice to have a lens an assistant could reliably pull focus on when shooting video.

Thanks

I have a couple of Canon EF L lenses. The focus ring is independent of the AF mechanism and does not move. They are always active, though, so I think they would work for your purposes.

Edit: Ooops, never mind. I think I misunderstood your question.

jogle
Oct-25-2009, 02:58 AM
there's some sigma lenses with a push pull clutch that will give you what you want, and you can also AF when needed.

my 15-30mm sigma has it and is optically quite good.

pyry
Oct-25-2009, 03:16 AM
Does anyone know if any of canons EF/EF-S lenses have non-electronic focus rings? Meaning, the focus rings DO NOT spin endlessly? I presume this would mean the lens is non-AF. I ask because it would be nice to have a lens an assistant could reliably pull focus on when shooting video.

Thanks

There only a couple of lenses in the Canon range that have electronic focus rings (the 85/1.2L and 50/1.2L have manual focus by wire).

Most USM lenses have friction coupled focusing rings, these too 'spin endlessly' past the stop.

If you need a lens that can disengage the focus entirely, there are a couple from Tokina that have clutches for both the AF-motors and the focus ring - these can therefore lock focus reliably.

ziggy53
Oct-25-2009, 07:12 AM
Does anyone know if any of canons EF/EF-S lenses have non-electronic focus rings? Meaning, the focus rings DO NOT spin endlessly? I presume this would mean the lens is non-AF. I ask because it would be nice to have a lens an assistant could reliably pull focus on when shooting video.

Thanks

Zeiss makes some manual focus lenses of very high quality and manual focus in a Canon EF mount. Many manual focus Nikon AI and AI-S lenses can be adapted through a simple adapter to Canon EF.

ARRI-Zeiss 35mm format cinematic lenses may also be adapted.

http://www.zeiss.com/C1256A770030BCE0/WebViewTopNewsAllE/91CA1DD9ED2D3E7DC12574C20034047F?OpenDocument

http://www.bobatkins.com/photography/reviews/zeiss_for_eos.html

http://www.novoflex.com/en/products/adapters/adapter-finder/

For accurate rack/pull/follow focus you will also want a coupler for the focus puller. Redrock makes such a rig:

http://www.redrockmicro.com/redrock_dslr.html

... and here is an image showing its use with a Canon 5D MKII (Vincent Laforet seminar, not my shot):

http://farm4.static.flickr.com/3350/3584004335_56c04720e0_b.jpg

BGtom
Oct-25-2009, 09:16 PM
Wow! Thanks guys. Very helpful. Greatly appreciated.