How Does an Auto Focus Camera Lens Actually Work?

Many modern cameras, including smartphones, include an auto focus feature. This means you can blur background features and increase sharpness around the subject. You’ve used the auto focus feature countless times without even realizing it. Here, we zero in on how an auto focus camera lens works and what makes it unique to today’s photography.

What Is Auto Focus?

Auto focus is a specifically designed algorithm that reduces the pressure when there is a desire for a perfectly in-focus photo or subject. The unique software enables the camera to do all the work adjusting to the surroundings accordingly.

So, what does this mean? The camera can focus on a subject and blur the background through an automatic sensor. There are two different types of auto focus a photographer can use: active and passive.

Active Auto Focus

Active auto focus uses the relay of a beam of light, typically red, to tell the device the distance between the camera and the object. Once the camera receives this information, it can adjust the focus ring and lens per the needs of the image. Active auto focus is often best for lowly lit scenarios where passive auto focus feature would have trouble automatically adjusting. Active auto focus also works to shoot a nearby subject.

Passive Auto Focus

Passive auto focus is one of the most typical forms of focus, common to smart devices and DSLR cameras. This algorithm’s design helps detect where to line up the focus ring by pulling a set of like images from the mirrors. You’ll consistently achieve a clear photograph with passive auto focus.

Auto Focus Compared to Manual

Let’s compare auto focus to manual to understand why one may suit you more than the other. Traditionally, a more seasoned photographer will find that auto focus can benefit their work and serve them well. Many landscape, portrait, and blog photographers will use auto focus for its ability to provide crystal clear images.

In contrast, manual focus forces the photographer to play a guessing game with pertinent factors such as distance, focal length, and lens type. If the subject moves slightly, you may have to reset the settings to refocus the shot. Still, many filmmakers prefer the manual focus feature because of its performance in lowly lit scenarios.

After understanding how an auto focus camera lens works, it’s clear how beneficial it can be to your kit. Complete your custom camera kit with a quality Samyang auto focus lens and watch your work soar to new heights.