In photography and video, a lens’s aperture is a set of blades that open and close to control the amount of light passing through the lens. It is part of the Three Elements of Exposure.

The way that the number is represented is called an F-stop, and it’s labeled as “f/” followed by a number like 1, 1.4 ,2, 2.8 , 4 , 5.6 , 8 , 11 ,16 , 22. These are all full stops, but you may also see numbers like 1.2, 1.8, 3.2, 4.5 , ect. These examples instead follow a 1/3 stop.

This article has a great chart of the different measured stops

Similarly you may find T stops on cinema lenses, which are measured more extensively for motion picture. More on T stops here.

Summary

Aperture has a large play in the DOF (Depth of Field). Depending on your subject, you may want to open or close your aperture in order to create a greater depth of field. For example, if you are shooting landscape photography, then you may want a greater depth. And with portraits, you might want isolate your subject from other details in the frame. If you are just starting out, a great option to learn DOF is a 50 1.8 (Nifty-50). These are typically inexpensive, and you’ll be able to see the specific changes in DOF (more specifically on the shallow end).

The following image was taken several years ago with my old Canon 60D and Canon 50mm F/1.8. this camera and lens can likely be found together used for sub $200

This page contains Amazon affiliate links. If you choose to purchase one of these products, we will be compensated and at no cost to you. This helps us to continue writing quality content for readers like