Let’s take it back to the basics today. How does Aperture work?
Aperture controls how much light is let into your lens and the depth of focus of a lens.
The aperture is designed after your eye. Yes… your eye! Let’s focus on your eyes for a moment. What happens to your iris when the light is low or dark? The iris opens up bigger. And when it is bright… the iris goes smaller. The smaller the hole, (or aperture), the less light is let through.
The aperture in a lens works the same way.
A few terms:
depth of focus: the distance in front and behind your picture’s main subject that is also kept sharply focused. It’s also sometimes called depth of field.
stop down: close down the aperture to a smaller diameter. (letting less light in the lens and making more of the image in focus)
open up: increase the aperture to a larger diameter. (letting more light in the lens and making less of the image in focus)
The aperture on a lens is calculated on a scale of f-stops. (these are fractions of the focal length of the lens.) Because f-stops are fractions, the larger the f-stop number, the smaller the aperture, and vice versa.
For example, if you “stop down” from f5.6 to f8 (this is one stop), you will decrease the amount of light entering through the lens by HALF. And if you open up 1 stop from f5.6 to f4, you double the volume of light entering through the lens. I know it’s a little confusing, but if you think of them as fractions, then it makes better sense.
So next time you go to take a picture of someone or something… stop and think about your aperture. Do you want to have the whole landscape in focus?
Like this: I used and aperture of F11
or do you want just a small amount in focus?
Like this: I used and aperture of F2.8
It’s totally up to you! That’s what is so neat about photography. You are the artist. You create the picture!
Come back next Tuesday for more tips and tricks! 🙂