Focal length vs. field of view?

[6x6TLL]

I've been doing some research, been curious about trying out LF at some point, and have been reading about lenses.

One thing that isn't clear to me, most lenses seem to be of some "standard" design, requiring approximately the same bellows draw as focal length to focus at infinity. There are special telephoto designs that allow shorter bellows draw for full focus.

What I'm curious about is angle of view and focal length. In MF, where I've spent the last 20 years, if I want to foreshorten the distance between a subject, the midground and background, I know that I can use a telephoto lens, from 150-300mm or so to get that effect. The opposite also applies, if I want to create an impression of even greater space and distance, making distant mountains almost tiny in the background, I can mount a wide angle lens, 35-50mm or so to achieve that. In both cases my subject could still be the same size and distance from the camera, but the perspective between subject and the rest of the composition would change.

My question is does this carry over to working in LF? Will a 4x5 camera with a 450mm lens create the same foreshortening, or on the other end, will a 75mm really create more distance? Or does it not work the same way due to the bellows and movements, and one uses movements instead to create some of the same effects?

Hope my question makes sense.

[Bob Salomon]

Exactly the same. Except you can control the plane of sharp focus as well as the shape of the object and the apparent placement of the camera by using camera movements.

If you are shooting 6x6 with a Rollei SL66 you can also control the plane of sharp focus but you would still not have the other movements.

[Leigh]

Hi 6x6,

The distance from the rear lens node to the film equals the optical focal length.
This is true for all lenses, by definition.

But the location of th rear node relative to the physical lens varies greatly.
For example, "normal" lenses have a rear node near the shutter plane.
Wide-angle lenses have a rear node significantly behind the rear lens element.
And telephoto designs have the rear node way out in FRONT of the front lens element.

You need to consult the datasheet for each lens to determine where the rear node is.

The spec that determines bellows draw is called the "Flange Focal Length", or FFL.
That's the distance from the lensboard to the film.
It may be quite different from the optical focal length.

- Leigh

[Pfsor]

What I'm curious about is angle of view and focal length. In MF, where I've spent the last 20 years, if I want to foreshorten the distance between a subject, the midground and background, I know that I can use a telephoto lens, from 150-300mm or so to get that effect. The opposite also applies, if I want to create an impression of even greater space and distance, making distant mountains almost tiny in the background, I can mount a wide angle lens, 35-50mm or so to achieve that. In both cases my subject could still be the same size and distance from the camera, but the perspective between subject and the rest of the composition would change.

My question is does this carry over to working in LF?

Imagine a lens that has the angle of coverage sufficient for a 4x5 film format. If you now limit, with a mask on the film plane, the format to a 6x6 film format the lens doesn't know it, the perspective neither, it is still the same, it won't reorganize itself because - on the film - you have limited the lens angle of view.

[Corran]

Perspective, and relationships between foreground and background, is controlled by the camera location. The lens only controls how much of what you see is projected onto the film.

[Jim Jones]

When shopping for LF lenses, consider the lens coverage in comparison to film dimensions. To use view camera front movements, the lens should cover more than the film size.

[Bob Salomon]

When shopping for LF lenses, consider the lens coverage in comparison to film dimensions. To use view camera front movements, the lens should cover more than the film size.

To use front or back movements! Especially if the camera uses base tilts!

[Pere Casals]

Just I'd add that in this chart:

https://lensn2shutter.com/angleofviewchart.html

You have the AOV for different focals and formats...

You can find the equivalent focal for LF format compared to a 35mm camera.

As it has been said yet, LF delivers same perspectives than smaller formats, motivation for shooting LF comes from other factors.

[6x6TLL]

Perspective, and relationships between foreground and background, is controlled by the camera location. The lens only controls how much of what you see is projected onto the film.

But the closer the camera is to the subject, the greater the amount of distortion, right? This seems most apparent in architecture and portraiture. The lens is determining the field of view (techically the angle of view, and together with the film dimensions determine the field). So I'd still want a 210-350mm lens on 4x5 for portraiture, right? A 150mm would be like a 50mm in 35mm, not the best choice in most cases for a portrait.

[Corran]

Perspective distortion will be more apparent with wider lenses, especially in the corners of the frame. For portraits it depends if you mean full-body, headshot, or something in-between. Plenty of folks use ~150mm lenses for portraits - a longer lens is not a hard and fast rule for this. But in some cases it's probably a better choice.