Nikon lenses on F350

[Steve Phillipps]

Anyone know what the back focus distance in on the XDCam 1/2" mount? Wondering if it was possible to make a optic-less adapter for putting Nikon stills lenses on it. It's not possible to do it on a 2/3" Sony bayonet as the ffd won't allow it, but easy on 1/3" cams. Is the 1/2" somewhere in between?
Steve

[Alister Chapman]

The FB distance is about 45mm on a 1/2 inch camera. most of that is through the glass of the prism. I can just about bring a Canon SLR lens to focus on my F350 by holding it up tight against the lens mount. If you were to add any kind of adapter I don't think it would be possible to achieve focus. The EX3 will be different as it has a thinner ND filter system and the lens mount has been designed to bring the lens as close as possible to the sensors. At NAB there was a range of adapters on show for various DSLR lenses for the EX3. This is one of the areas that I fully intend to explore as I have some shoots coming up later in the year that will need long lenses and I am thinking of using stills telephoto lenses.

[Steve Phillipps]

If it's 45mm then it'd be close! You can adapt Nikon lenses for Canon EOS (46.5mm to 44mm ffd), so that allows for 2.5mm thickness for the adapter. If it's just 1.5mm then maybe it'd be too thin.
Steve

[Morton Molyneux]

Century Optics now part of Schneider have made adapters for years. They have both 2/3" and 1/2" to Sony Bayonet available as well as to C mount lenses. Some friends have used one for years on Betacam SP with 400mm and up Nikon lenses. There was so much magnification that they adapted a hunting telescopic sight to the camera to make it easier to locate what the camera was seeing. I believe they have one for their F350 but will have to confirm that.
Here is the Schneider link.
http://www.schneideroptics.com/ecomm....aspx?CID=1094

cheers

Morton

[Steve Phillipps]

From the site it says it's an optical adapter, which I'm keen to avoid as it'll reduce optical quality. I'm wondering about a simple metal adapter.
Steve

[Paul Curtis]

Originally Posted by Steve Phillipps

From the site it says it's an optical adapter, which I'm keen to avoid as it'll reduce optical quality. I'm wondering about a simple metal adapter.
Steve

You'd get quite a big focal length multiplier, around 5.5x and you'd be using a very small centre part of the lens so you may run into resolution limits of the glass. I've adapted some canon lenses onto c mount (for an experiment) so if you can find the right adaptor it'd probably work but unless you need super telephoto lenses it may not be that practical...?

cheers
paul

[Steve Phillipps]

It's telephotos that I'd be wanting so that's not a problem. Centre part of the lens is always the best, but I know what you're saying about resolution limits. In practice I've not really noticed the thoeretical resolution problems with putting lenses designed for larger sensors/film on smaller ones. I know that a lens for a 1/3" chip for example has to be made to resolve a lot more lp/mm than one for a 2/3" chip as the photosites are so much smaller - which in effect means that the cheap stock lens on a JVC HD100 should reolve more detail than a Zeiss Digiprime! But I think in real world shooting the difference is small - though I've never done enough really good testing to say it with hand on heart. But I have used my Canon teles (300, 150-600 and 800) on Sony 750 with what looked to me very good results.
Steve

[Morton Molyneux]

Just heard from my friends with the adaptors. The Century 1.6 tele adapter worked good on Betacam but is soft on F350.

He has a older Nikon to Betacam adapter, made by Nikon # TM-B1, no magnification just 1:1, It was made for 2/3 inch lenses so he uses it with the 1/2 to 2/3 adapter on their F350 with 300mm and 600mm Nikon lenses. says it's sharper than their Fuji 18x5.5 BERM.

cheers

Morton