Bellows Extension

[Mike A]

Is there a link or chart giving the amount of bellows extension required for various different focal length lenses? I need to know what bellows extension is required for a 750mm and a 1000mm lens.

Mike

[df cardwell]

The back focus of a lens varies. Watcha got ?

[David A. Goldfarb]

Generally, for practical use, you want at least 25% more bellows than the focal length of your longest lens (less if your longest lens is a tele design). If this is for a field camera, bear in mind that more bellows adds more weight (both of the bellows and the camera necessary to support it at those extensions) and can make it harder to work with wide lenses.

[TheFlyingCamera]

Also, how close do you want to be able to focus with said lens? If you want to use your ULF for portrait work, you need to be able to focus to 1:1, which is generally 2x focal length of the lens. This of course creates a HUGE bellows to have to manage, especially outdoors where it can turn into a giant sail.

[Mike A]

The back focus of a lens varies. Watcha got ?

21" of bellows draw.

[Mike A]

Also, how close do you want to be able to focus with said lens? If you want to use your ULF for portrait work, you need to be able to focus to 1:1, which is generally 2x focal length of the lens. This of course creates a HUGE bellows to have to manage, especially outdoors where it can turn into a giant sail.

Strictly landscape, so I'll be closing down to f64 and f90 mostly.

[Amund]

21" of bellows draw.

21" is 534mm, so using 750mm or 1000mm non-tele lenses is not possible on your camera...

[David A. Goldfarb]

21" of bellows draw.

With 21", I'd say 450mm or 19" would be the longest lens that you can use practically without adding an extension lensboard or extending the camera in other ways.

[Mike A]

I've been informed that at least 28" is required and my Phillips is short, a rail design in this format is looking good right about now.

Mike

[Mike A]

With 21", I'd say 450mm or 19" would be the longest lens that you can use practically without adding an extension lensboard or extending the camera in other ways.

Thanks Dave, I'm using a Nikon 450 right now. i find myself compress my subject matter more and more so I think eventually will have to make a change.

Mike