View Full Version : JVC at OPTEX


Martin Costa
May 5th, 2005, 02:37 AM
Hi guys/gals, just thought I'd let you know of a link I came accross on the optex site. Seems they were given a pre-production model to play about with. http://www.prohd.co.uk/

Glenn Gipson
May 5th, 2005, 05:04 AM
I wonder if that adapter and lens would help the camera have a shallower DOF. Does anybody know?

Chris Hurd
May 5th, 2005, 07:03 AM
Sorry Glenn, that's just an an lens mount adapter, very similar to the Canon EF adapter in principle. That adapter housing is much too small to involve a relay lens, therefore it won't preserve depth of field.

Guy Barwood
June 5th, 2005, 04:48 AM
It would preseve DOF wouldn't it? It won't preserve Field Of View though (there will be a significant FOV multiplication factor)

Chris Hurd
June 5th, 2005, 11:56 AM
Nice to see you here, Guy. I wouldn't say that the adapter preserves DOF, because those lenses on a still camera will give you a highly variable deep or shallow depth of field depending on how you use them. But what the adapter does, since it gives you a field of view equal to multiplying the focal length of the lens by a factor of seven times or so, is an extremely shallow depth of field all the time. However its applications are pretty much limited to extreme-telephoto uses, such as wildlife, surveillance, etc. It would be impractical to use in a narrative filmmaking environment because the camera would have to be set up a mile away to get anything other than an extreme close-up.

Guy Barwood
June 6th, 2005, 02:17 AM
With the FOV thats what I was thinking, however with the DOF, I thought it would be the same as using the lens on a 35mm body. So the image seen is just a tight crop of the centre of the image circle, but the DOF of the lens created at a particular setting would be the same as on a 35mm body.

You say a 7x factor, which is a lot indeed, I have a 14mm f2.8 Nikon which would result in a 98mm FOV, but at f2/8 the DOF would be nice and short. Then again the 14mm DOF is pretty long even at f/2.8... If only they could shrink the image circle as well!

Chris Hurd
June 7th, 2005, 07:28 AM
Good points! Too bad we're stuck in "extreme telephoto only" with that option. *frown*

Jacques Mersereau
June 7th, 2005, 08:08 AM
Good points! Too bad we're stuck in "extreme telephoto only" with that option. *frown*


***DROOL*** :)