I will start by saying that I am not a very technical person & I tend to the more artistic side of things. But I know the basics of the technicalities, so that I can create my photographs in the way that I want - well, most of the time! Therefore my explanations may not be the best technically, but hopefully you’ll be able to learn something anyway!
Aperture is the opening in your camera lens which light travels through. Aperture determines 2 things - your depth of field & how much light you are letting into your camera. Depth of field is how much of your photograph is in focus.
When I was first learning about using my camera in manual, I found aperture a difficult concept to grasp in relation to the size of the opening vs the f-stop number. The larger the aperture (the opening), the smaller the number (the f-stop). I began to to think of it in this way: With a smaller number (f1.8 for example), there is less in focus. With a larger number (f16 for example), there is more in focus.
Here is an example of what 4 different aperture settings look like at the same distance from the subject:
At f1.4, the background is a beautiful bokeh. My daughter’s face is in focus, but we can see her ears & barrette are dropping out of focus. At this distance there is an extremely shallow depth of field with about 2” in focus. At f4, the background is still very soft, but has a little more definition than in the first image. My daughter’s ear is in focus, & then it begins to drop off with her braid, so in this case there is maybe 4” or so in focus. In the 3rd image, at f9, the subject is completely in focus & while the background is soft, you can see details. In the last image at f16, the depth of field is much greater, & even the stump in the far background is nearly in focus.
You will also notice the shutter speed changed drastically in these 4 images. Because the aperture was so large in the first image, it lets in a lot of light, so I needed a very fast shutter speed to ensure the image wasn’t overexposed. As the aperture becomes smaller, there is less light coming in, so I decreased (slowed) my shutter speed to allow more light in that way. In the last image at f16 which is a very small aperture, I didn’t want to decrease my shutter speed any lower, so I had to increase my ISO to allow enough light in, for the image to be properly exposed. The depth of field is also determined by how far you are from your subject.
In the 2 photos above, I used the same aperture of f1.4. In the first image I was very close to the subject, so there is very little in focus. In the second image, I was several feet from the subject so she is completely in focus, most of the log she is sitting on is in focus, & the background is much clearer than in the first image.
As a newborn photographer, it is important to be very familiar with aperture & what effect it is going to give your photographs. I want a shallow depth of field, so the background is blurred & the baby stands out against it. These images are shot in studio with lights & I have the same aperture of f2.2 for both.
For the first image, I am inches away from the baby. In the second photograph, my camera is about 2 feet from the baby. I am close enough that I can reach out & touch the baby. I am very close in both cases, but you can see the difference in the effect on the same background. In the first case, it appears to be a completely solid color, but in the second you are can see a little of the texture & mottled colors of the blanket.
For groups of people, the general rule of thumb, is your aperture should be greater than the number of people in the photograph. If you have 3 people in your photo, your aperture should be at least f4. If you’re very close to the subjects, such as a head & shoulder shot, you may have to have a smaller aperture than that, perhaps f5.6. If you are further away & taking full length shots, you may be able to open up more. It took me quite a while to get a good feel of what my aperture should be when I was shooting a photograph with multiple people, so I still tend to err on the side of caution, & use a smaller aperture (a larger number).
In studio, I usually shoot at f4 where the family is very close to each other, such as the first image below. With the large family group, I felt comfortable at shooting at f11. I had the camera on a tripod, several meters (yards, for my American friends!) from the group & also had everybody lined up on a similar plane - they are only 3 people deep at the most.
If you are struggling with what aperture you should use & how much is going to be in focus, you may find this depth of field calculator helpful. http://www.dofmaster.com/dofjs.html There are also apps available for smart phones if you do a google search. If you’ve made it this far, thanks for reading....I hope you’ve found this helpful!
WEEK 2 CHALLENGE: Okay, so this week you should be continuing your practice in all manual mode, don't go back now, you are doing great! This week we want you to continue working on proper exposure, but add in using your aperture to create the look you want for your photograph. Please experiment with both a more open aperture (blurrier background) and a more closed down aperture (background more in focus). Go like the Kensie M Photography Facebook Page and post your favorites from the week there! We can't wait to see what you are working on. And remember we love questions, so feel free to post them in the comments section!
Lynnea is the owner of New Beginnings Photography, in Edmonton, AB. She is a family & child photographer, but specializes in maternity & newborn. Since she was a child, she loved photography & a camera was never far from her. Throughout her adult life she has taken photography courses & workshops, ﬁrst for general interest & then as she began to consider photography a business rather than just a hobby. Lynnea is a mom of 2 girls - 6 & 4 years old. When her daughters were babies, she became passionate about maternity & newborn photography & built her 3 year old business on those genres. You can check out her website here for more information and be sure and go like her on Facebook!