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-   -   1/2" lens for Z7U (https://www.dvinfo.net/forum/sony-hvr-z7-hvr-s270/125063-1-2-lens-z7u.html)

Marius Boruch June 30th, 2008 08:34 PM

1/2" lens for Z7U
 
Will this lens work with z7u - Canon 16x7 KRS lens I have on my Panasonic DVC200; http://www.canon.com/bctv/products/p...krs_for_us.pdf
do I need and attachements???

thnaks in advance

Tim Dashwood July 1st, 2008 09:31 AM

You will need the Fujinon ACM-12 1/2" to 1/3" adapter. (about $700)

http://www.bhphotovideo.com/images/l...ges/191295.jpg

Marius Boruch July 1st, 2008 09:37 AM

Thanks Tim.
Will it be some multiplier factor issue when using these lens;

Zach Love July 8th, 2008 02:16 PM

Quote:

Originally Posted by Marius Boruch (Post 901551)
Thanks Tim.
Will it be some multiplier factor issue when using these lens;

*sigh, I have been busy and have yet to put this into a nice webpage w/pics & charts & everything.

the short version, a 50mm lens is a 50mm lens is a 50mm lens, no matter it being on a 35mm film camera, a 2/3" betacam or a 1/3" Sony CMOS Z7.

this Canon looks like it goes from 7mm to 112mm lens. the Z7 stock lens goes from about a 4mm to 54mm. so when you have the Zeiss or the Canon at 20mm, they will be the same. when you have them at 50mm they will be the same. the difference is the Zeiss will go wider, the Canon will go tighter.

now if you take the Canon & put it on a 1/2" camera while @ 7mm, then the Z7 @ 7mm, the FOV (field of view) WILL be different. the FOV will be wider on the 1/2" than the Z7 (or any 1/3" camera).

this whole "magnifying" issue bugs me b/c I don't think people really understand it & keep repeating bad understanding of it. it took me a long while of reading to really figure out that a 50mm lens will always be a 50mm lens, but the FOV of a 50mm lens changes depends on size of the negative / chip.

Tim Dashwood July 8th, 2008 05:14 PM

Quote:

Originally Posted by Zach Love (Post 904660)
this whole "magnifying" issue bugs me b/c I don't think people really understand it & keep repeating bad understanding of it. it took me a long while of reading to really figure out that a 50mm lens will always be a 50mm lens, but the FOV of a 50mm lens changes depends on size of the negative / chip.

Agreed. This has been a pet-peeve of mine for years. I try to at least correct people by referring to it as a "cropping factor" which more effectively describes what happens.
The manufacturers don't help the confusion with erroneous phrases like "the focal length is increased 1.3 times with a 1/2-inch lens adaptor" and publishing lens specs with "35mm equivalent focal lengths." Sony did just that with the Z7/270 brochure (See page 6) and they didn't even mention the real focal length capabilities of their lens! I still don't know what the widest focal length of the "wide" lens is.
And what EXACTLY do they mean by "35mm"???? Are they referring to SLR 35mm, Cinema Super-35 or Academy 35? These are all very different. Who do they expect to be reading this brochure?

George Kroonder July 9th, 2008 04:55 AM

Quote:

Originally Posted by Zach Love (Post 904660)
this whole "magnifying" issue bugs me b/c I don't think people really understand it & keep repeating bad understanding of it. it took me a long while of reading to really figure out that a 50mm lens will always be a 50mm lens, but the FOV of a 50mm lens changes depends on size of the negative / chip.

The way I explain it is to have them imagine a projector that's projecting a scene on the wall, lets say 36" diameter. Then "take" a sheet of paper (A4/Letter/Legal, whatever) and then hold that up to the wall. That's what a smaller sensor sees of the scene.

For a projector we have to "zoom in" to get the whole scene to fit on the piece of paper. With a camera being the "oposite" of a projector you have to "zoom out", ie use a smaller focal length to capture the scene.

George/

Ryan Valle July 9th, 2008 09:54 AM

so i take it that nobody makes an adapter that will adjust a lens so that it will not only fit on the mount but also adjust the image coming in to fit the chip size?

Tim Dashwood July 9th, 2008 04:29 PM

Quote:

Originally Posted by Ryan Valle (Post 905029)
so i take it that nobody makes an adapter that will adjust a lens so that it will not only fit on the mount but also adjust the image coming in to fit the chip size?

Not for bayonet style mounts. It isn't worth it since Fujinon and Canon make some top-notch 1/3" zoom lenses designed for HD.
There are numerous PL and Nikon mount adapters that do that (mini35, RedRockMicro M2, Brevis, Letus100, JVC HZ-CA13U, etc.)


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