Understanding Aperture

love playing with the Aperture and using it creatively in my photography, and by the end of this tutorial I will make sure you have a good Understanding of Aperture.
You will also learn: How to use it to your advantage? When to use which aperture? What does stopping down mean? What does wide open mean? Why are those f/1.2 & f/1.4 lenses so expensive? What exactly is Depth of Field? What is a bokeh, and what causes it?

I decided I’m going to start this Aperture tutorial with an image I just took a few days ago at Soon’s Orchard in Orange County NY. I stopped there to pick-up a few of their absolutely amazing apple cider donuts and some apple cider to wash it down As I was heading back to my truck stuffing my face with a nice warm fresh donut I noticed they had this huge garden of flowers I needed to check out closer. I knew right away that I was going to want to isolate the flowers from the background, and a high focal length lens plus a large aperture are great for these types of compositions. So I inhaled the donut and grabbed my gear. The garden was gorgeous and I took well over 100 shots. I knew these images would work great for an aperture tutorial

In the image below I really wanted to isolate the subject from the background and have that nice buttery bokeh for a backdrop. So I got as close to the butterfly as I could while still being able to focus and took the shot. I was about 2 meters away. I used the Canon 5D Mark II with the Canon EF 100-400mm f/4.5-5.6L IS USM lens @ 400mm, set to f/5.6 @ 1/1600sec, ISO 320. So the combination of the high focal length (400mm), being at the minimum focus distance, and the “wide open” Aperture created this composition.

The Aperture is the mechanism that controls the light flowing though your lens in increments known as f-stops. Basically the light travels through the lens like water through a pipe. The Aperture is the valve the can slow the flow of water, or in our case light down;) Check out the chart below, see what I mean? f/16 is barely letting any water (light) through, and f/2 is pretty much wide open.

Aperture settings are called f-stops and indicate the size of the aperture opening. Each f-stop lets in half as much light as the next larger opening and twice as much light as the next smaller opening. The most common F-stops are shown to the left, but most cameras can be set to 1/2 stops, or even 1/3 stops these days so you have more flexibility and control. Which is nice

Now, on Canon SLR’s there should be a shooting mode labeled Av, on Nikon’s it is just an A. That stands for aperture priority mode, and is by far the most popular shooting mode for the average photog imo. I use Av most of the time unless I’m using studio lights or flash, then I move to manual mode. Av mode is great, because if you adjust the dial on your camera to your preferred aperture, the aperture will remain constant as your camera adjusts the other settings for you (shutterspeed, ISO).