Understanding aperture is one of the fundamental keys to really learning about your camera and getting the most out of your pictures. It can sometimes be a little confusing to grasp though. The aperture or f/stop you select will determine how much of your picture will be in focus.
Depending on the lens you have, apertures can typically go from 1.2 to 22. These numbers refer to how open or closed your lens is. The tricky part (for me at least) was remembering that they correspond in the opposite way that you would think.
A very open lens, which will let in the greatest amount of light and provide you with the shallowest depth of field or give you the blurry background (the plain english translation) is the lowest f/stop or aperture your lens has. For those with the 50mm, this would typically be 1.8 or 1.4. If you have the lens that came with your camera, this is probably 5.6 but you’ll have to check to be sure.
In this picture taken at with an aperture of 1.2, you can see that the focal plane is very small, with a focus just on the cluster of leaves here, and rendering everything else blurry, or creating a “bokeh” background. Bokeh is a photography term derived from the Japanese language that literally means watercolor, and is an accurate representation of what the background of a picture with a very wide aperture looks like.
The smaller your aperture, the more of your picture that will be in focus, but less light will be allowed in through the small opening. A closed aperture would be considered f/22, or the highest your lens goes. Using an aperture or f/stop this high would result in a very deep focus, and almost no background blur to your photos.
Here is the same image as above, but taken at f/16. You can now see all of the surrounding details.
In order to understand how to adjust the aperture, and what it does to your pictures, this week we would like you to explore Aperture Priority mode on your cameras. Canon users, this is the AV mode. On Nikons, it is the A on your dial… but you guys already knew that, because you read your manuals last week, right? ;) Using this mode will allow you to focus on just the aperture, and let the camera choose your shutter speed. You will have to select your ISO, but we’ve given some suggestions below.
Okay, so once you’ve set your camera to Aperture Priority mode, we’d like you to find some kind of stationary object, if you can go outside that would be great, but bundle up, we aren’t responsible for frost bite! If you take your pictures outdoors, first try an ISO of around 200 and review your image to see how that looks. If it’s too dark, bump it up to 400. If you have to take your pictures inside, you’ll probably need to bump that ISO way up to 1250 or even 1600. They won’t be the most beautiful pictures you’ll ever take, and they may look quite grainy, but they will allow you to focus on just the aperture, which is the important part.
Here’s the official homework:
1. Set your f/stop to the lowest possible setting your lens allows and adjust ISO as mentioned above. Double check your manual if you’re not sure how to make these changes. Compose your image and focus on just one thing, and take the picture.
2. Move your aperture setting up to around 1/8 and recompose your image focusing on the same spot. Click away!
3. Finally, close your lens down to the smallest aperture (probably 1/22) and recompose again with the same focal point. Take that picture.
Now upload those three images onto your computer and check out how the different apertures gave you three totally different pictures!
Here is a quick example for you using the little Mexican figurines we have saved from our honeymoon.
This first shot is at f/1.4. Notice how only the man in the front is truly in focus, and everything else is quite blurred.
Now, the shot taken at f/8. You can now see the other characters quite clearly, including that chip on the guy’s foot to the right. Hmm.. I’ll have to ask my husband about that. Though the figurines are more in focus, notice that the background is still a bit blurry.
This last shot was taken at f/22. You can now see that the focus is deep and wide, with the entire image in focus right down to my ugly blinds and the stack of magazines back there on the table.
Now that you’ve seen an example, go try it out. We can’t wait to see the results!
As a final wrap up, your key words from this lesson are aperture - which describes the size of the opening of your lens and determines how much light is let in as well as the amount of your picture that will be in focus. f-stop is the corresponding number typically ranging from 1.2 to 22 on your lens that will allow you to choose a very WIDE aperture (a low number) or a very CLOSED aperture (a high number). A shallow depth of field is seen when you’ve used a very wide aperture, and a small portion of your picture is in focus, with the rest very blurred, or containing a lot of bokeh. A deep depth of field is the result of a very closed aperture and most if not all of your picture is in focus with very little blur.