How Zone Focusing is a garrison of realities and helps me for street photography

In these days we are reading of AI more implemented on the cameras. For this reason I want to publish this post about hyperfocal and zone focusing.

I used the zone focusing technique for this shot

Zone focusing and freedom

Using the zone focusing technique allows me to do better my kind of street photography. Because the camera is ready as soon as you turn it on. And shooting at the last useful moment is my prerogative.

The result is that my approach improves and I feel freer.

Zone Focusing and Hyperfocal: the differences

I see there is still a lot of confuision in many people. zone Focusing and Hyperfocal is not the same.

Hyperfocal is the distance at which, by focusing the lens, everything from half this distance up to infinity is sharp.

Zone focus, on the other hand, is a technique in which a focus distance is preset and an aperture is used to obtain a depth of field such as to have a certain area of the scene in focus.

The main difference is therefore that hyperfocal focuses on a specific distance to obtain sharpness from half of it to infinity, while zone focus presets a sharpness zone based on aperture and focus distance.

Hyperfocal

To hyperfocal focus with a lens, follow these steps:

Calculate hyperfocal distance: Use a formula or table specific to your lens and aperture. The formula is:

Hyperfocal distance = f2/ N * c

Where 𝑓 f is the focal length of the lens, 𝑁 N is the f-stop (aperture) number, And 𝑐 c is the acceptable circle of confusion (usually 0.02 mm for full-frame).

Set the lens: Rotate the focus ring on your lens to this calculated hyperfocal distance.

Compose and shoot: Now, everything from half the hyperfocal distance to infinity will be in focus. For example, if the hyperfocal distance is 5 meters, focus at 5 meters. So, from 2.5 meters up to infinity it will be clear.

Zone Focusing

To apply zone focus with a lens, follow these steps:

Choose aperture (f-stop): Decide on the aperture you want to have a certain depth of field (for example, f/8).

Set the focus distance: Decide the distance at which you want to preset the focus (for example, 3 meters).

Check the depth of field scale: Use the depth of field markings on the lens to check the sharpness zone. These markings indicate the range of distances that will be in focus for a given aperture.

Practical example:

Lens: 35mm on a full-frame camera.

Aperture: f/8.

Focusing distance: 3 meters.

Set the aperture to f/8 on your camera.

Rotate the focus ring until the 3 meters on the distance scale matches the center focus indicator.

Check the depth of field:

Look at the depth of field markings on the lens for f/8. Let's say the markings show that from about 2 meters to 6 meters everything will be in focus.

Compose and shoot:

Knowing that everything between 2 meters and 6 meters will be sharp, compose your scene with this sharpness zone in mind.

In practice, you have preset your camera to have a certain area (2 to 6 meters) that is sharp, making it easier to photograph moving subjects or scenes where it is not possible or practical to focus exactly every time.

In micro four thirds

To calculate the hyperfocal distance for a 14mm f/2.5 lens on a micro four thirds (MFT) system, we can use the 0.015mm circle of confusion, which is commonly accepted for MFT sensors.

Practical Steps

Calculate the hyperfocal distance: 5.23 meters.

Set focus: Rotate the focus ring to approximately 5.23 meters.

Compose your photo: Knowing that everything from approximately 2,615 meters to infinity will be in focus.

With this setup, you will be able to maximize depth of field and get a clear scene from 2,615 meters up to infinity.

The choice of aperture for hyperfocal focusing depends on several factors, including the desired depth of field and lighting conditions. Here are some considerations that can help you decide:

Desired depth of field

A smaller aperture (higher f-stop number, such as f/8 or f/11) provides greater depth of field, meaning more of the scene will be in focus.

A larger aperture (lower f-stop number, such as f/2.5 or f/4) reduces depth of field, but allows you to use shorter exposure times or lower ISO in low-light conditions.

Diffraction

Closing the aperture too much can lead to diffraction phenomena, reducing the overall sharpness of the image. On a micro four thirds sensor, it is generally recommended not to stop down the aperture beyond f/11 to avoid diffraction problems.

Light conditions

If you shoot in low light, you may need to use a wider aperture (such as f/2.5 or f/4) to avoid long exposure times or high ISO values that could introduce noise.

Optical quality of the lens

Lenses have an optimal aperture where sharpness is greatest, often located between f/4 and f/8.

Recommendation for the 14mm f/2.5 on Micro Four Thirds

For a balance between depth of field, sharpness and light management, an aperture of f/5.6 or f/8 is usually ideal:

f/5.6: Good compromise between depth of field and sharpness, while still maintaining a decent amount of light.

f/8: Greater depth of field and still a good level of sharpness, suitable for landscapes or scenes where you want to make sure a large part of the image is in focus.

Result

When you set your lens at 1.63 meters with an aperture of f/8, everything from half that distance (about 0.815 meters) up to infinity will be sharp. This setup is ideal for landscapes or other situations where you want a large depth of field.

In micro four thirds I am used to shoot at f4. We have to consider:

Shooting at f/4 for hyperfocal is absolutely doable, especially if you need more light or want a shorter exposure time. However, the depth of field will be shallower than at smaller apertures such as f/8 or f/11. Let's see how to calculate the hyperfocal distance for a 14 mm lens at f/4 on a micro four thirds system:

Take in mind

If you often shoot at f/4 and want to use the hyperfocal technique, that's great. However, be aware that the depth of field will be shallower than at smaller aperture values. To achieve maximum depth of field, you may consider stopping down to f/5.6 or f/8 when light conditions allow.

Conclusion

In a world where we leave everything to technology I still see using optical principles work better than any AF. Of course is always up to you, and depending by the camera. I can see a lot of errors by using the AF in my Olympus cameras. This is because of my way of shooting, but altso because when I turn on the camera the AF is not immediately ready. I tried also to keep the camera on: this works a little bit better and yet I can see the AF sometimes sleeps or not recognizing immediately the scene. When I use MF (Manual focus) I have the camera ready to shoot even from off/on. And the focus is most of the time more accurate. It is the magic of photography that is a science based on optics and where technology sometimes is not working that good.

A last thing: I am seeing camera manufacturers who started to propose cameras counting only with the electronic shutter: that is very bad. Blinded by the pursuit of artificial intelligence, they are forgetting that physics is very important in photography. But they continue to chase computational photography, showing little respect for photography and photographers. We have to fight this.