Quick Question- what is 'standard' lens for 20x24 format?

[dimento]

Very simple question, what is the focal length of as close to standard lens for 20x24 format cameras?

would it be something like 1200mm?

I'm guessing the lenses are rare as hen's teeth.

many thanks, D

[grzybu]

If by standard you mean focal length close to film diagonal then it will be about 31" (800mm). This will be equivalent to about 43mm in 35mm film format.

[dimento]

If by standard you mean focal length close to film diagonal then it will be about 31" (800mm). This will be equivalent to about 43mm in 35mm film format.

great, thanks, what would be the next step up then, and would the main contemporary manufacturers like Nikon, Rodenstock, Schneider have mad say an 800 and whatever the next step up would be?

[Mark Sampson]

Before you worry about what a 'normal' lens for that format is, do some research. Find out what the people who shoot 20x24 actually use; you might be surprised. It seems the usual rules about focal length (that apply to smaller formats) don't work as well scaled up to mammoth size. Two people who shoot 20x24 and post here are Tracy Storer and Monty McCutchen; I'd ask them.

[Sheldon N]

What is a "normal" focal length will depend on what you intend on shooting, primarily the degree of magnification needed. If you're shooting at infinity then 800mm will give you a normal field of view. However, if you intend to shoot portraits with a 20x24 then you are going to be in macro territory. Even a loosely framed portrait is going to be 1:1 magnification and will cut the field of view of your 800mm lens in half, giving it the angular field of view of something like a 1600mm lens and the resulting perspective of the photo will be more like a traditional short telephoto portrait since you'll need to back the camera up to frame the shot.

So think about how much magnification you'll need for the images you want in addition to the angle of view that you want for the images, since both are key factors in the lens choice.

[Steve Goldstein]

There was a 20x24 setup in the vendor room when the View Camera Conference was held in Massachusetts some years ago. It had a 600mm Fujinon-C mounted on it. I don't recall who was showing it or why, just the lens and that the camera was BIG.

[David Lobato]

What is a "normal" focal length will depend on what you intend on shooting, primarily the degree of magnification needed. If you're shooting at infinity then 800mm will give you a normal field of view. However, if you intend to shoot portraits with a 20x24 then you are going to be in macro territory. Even a loosely framed portrait is going to be 1:1 magnification and will cut the field of view of your 800mm lens in half, giving it the angular field of view of something like a 1600mm lens and the resulting perspective of the photo will be more like a traditional short telephoto portrait since you'll need to back the camera up to frame the shot.

So think about how much magnification you'll need for the images you want in addition to the angle of view that you want for the images, since both are key factors in the lens choice.

What Sheldon said. Plus, for portraits the bellows draw gets longer making the setup a little more difficult. The difference between an 800mm lens and 600mm lens can be significant. Remember 1:1 magnification needs 2 stops more exposure which adds the requirement for more intense lighting.

[dimento]

thanks for all the info guys, I don't have a camera yet but am mulling some ideas over in my head. Will speak to the members mentioned above who shoot 20x24, thanks, Damian

[adelorenzo]

20x24 Studios has some info about their camera:

What lenses are used on the 20×24 Camera?

The New York Studio offers focal lengths of 1200mm, 800mm, 600mm, 360mm, 210mm, and 135mm. Only the 1200, 800, and 600 were designed for the 20×24 format. Translated into inches these are 48 inch, 31 inch, and 24 inch lenses. The bellows of the camera extends from 17 to 60 inches and each of these lenses will provide different levels of magnification at different bellows extension. The 24 inch lens (600) has the most range of magnification, allowing landscapes at infinity all the way up to 1.5 times lifesize. The shorter focal lengths, which are actually 8×10 and 4×5 lenses provide magnifications from 1.5 times life-size all the way up to 10x. As magnification increases, depth of field decreases and subject to lens distance decreases. At extreme magnification, it becomes more difficult to light the subject, because it is so close and the bellows extension factor can lose up to 8 or 9 stops of light.

[dimento]

20x24 Studios has some info about their camera:

What lenses are used on the 20×24 Camera?

The New York Studio offers focal lengths of 1200mm, 800mm, 600mm, 360mm, 210mm, and 135mm. Only the 1200, 800, and 600 were designed for the 20×24 format. Translated into inches these are 48 inch, 31 inch, and 24 inch lenses. The bellows of the camera extends from 17 to 60 inches and each of these lenses will provide different levels of magnification at different bellows extension. The 24 inch lens (600) has the most range of magnification, allowing landscapes at infinity all the way up to 1.5 times lifesize. The shorter focal lengths, which are actually 8×10 and 4×5 lenses provide magnifications from 1.5 times life-size all the way up to 10x. As magnification increases, depth of field decreases and subject to lens distance decreases. At extreme magnification, it becomes more difficult to light the subject, because it is so close and the bellows extension factor can lose up to 8 or 9 stops of light.

that's really helpful, thanks, Damian