Image Circle and Vignetting

[Panoman617]

Would a larger image circle make less vignetting?

A Nikon 120mm SW F64 image circle is 312
VS.
A Schneider Super-Augulon F64 image circle 288

Would you need a ND center filter for the nikon lens on a 6x17 fomat?

Thanks

[engl]

Vignetting is not really tied to size of the image circle. The Schneider 72XL for example has more vignetting (at the same angle off center) than many 75mm Biogon-like wide lenses, even if it has a bigger image circle. The 72XL has close to cos^4 falloff while Biogon-like lenses have cos^3 falloff.

Between the two lenses you list, I'd expect them to be very close, but maybe someone who has compared them can tell you more.

[Bob Salomon]

Yes, they both can require a center filter to even out the fall-off (not vignetting). But Nikon never made any center filters for any of there wide angle large format lenses.

[Gem Singer]

The Nikon/Nikkor f8 120SW has been my favorite lens for many years.

I've used it for 4x5, 5x7, and 8x10. the only time it showed vignetting was when too much front rise was used on the 8x10 camera.

Haven't tried it with my new Canham 6x17 back, as yet, but my camera will probably run out of movement before that lens vignettes.

You may prefer to use a center filter when shooting transparency film. I have never found the need with B&W film.

A 77mm center filter for the 120SW is going to be quite expensive.

[Panoman617]

I have a Fuji center Filter ND 2x 77mm for my G617. Would that work on the Nikon lens? Bouth are 77mm.

[Gem Singer]

Yes.

[Bob Salomon]

I have a Fuji center Filter ND 2x 77mm for my G617. Would that work on the Nikon lens? Bouth are 77mm.

Maybe, Are you planning on using the lens on a view camera or a panoramic camera?
If a view camera will you be using camera movements? If so then you should use a center filter whose front is larger in diameter then rear thread of the filter. Some of the center filters used on the Fuji were the same diameter front and back and those could vignette when you do camera movements on the view camera.

[Panoman617]

Yes Bob I'm going to be useing it on a Shen-Hao 6x17. What would be a better filter?

Thanks

[Bob Salomon]

Yes Bob I'm going to be useing it on a Shen-Hao 6x17. What would be a better filter?

Thanks

As long as it doesn't vignette it is fine. If it does then you will need a wide angle designed CF like the Rodenstock, Heliopan or Schneider. They are much larger in front then in back. You will also need that type if you want to add a polarizer or ND to the CF.