Find a subject in front of a background with depth. Take a very close viewpoint and zoom in; you’ll need to be aware of the minimum focusing distance of your lens. Focus on the subject and take a single shot. Then, without changing the focal length or framing, set your focus to infinity and take a second shot. As you review the two shots, how does the point of focus structure the composition? With a shallow depth of field the point of focus naturally draws the eye, which goes first of all to the part of the image that’s sharp.
Achieving deep depth of field might appear easy compared to the difficulties of managing shallow depth of field. We’re surrounded by images made with devices rather than cameras, whose short focal lengths and small sensors make it hard to achieve anything other than deep depth of field. The trick is to include close foreground elements in focus for an effective deep depth of field image. Foreground detail also helps to balance the frame, which can easily appear empty in wide shots, especially in the lower half. When successful, a close viewpoint together with the dynamic perspective of a wide-angle lens gives the viewer the feeling that they’re almost inside the scene.
Again without moving the camera, select a very small aperture (perhaps one stop above the minimum to avoid diffraction) and find a point of focus that will give you acceptable sharpness throughout the entire field, from foreground to infinity. Take a third shot and add it to the first two to make a set.
The exercise is also a way of thinking about attentional focus. According to some of the most recent thinking in neuroscience, the left hemisphere of the brain attends more to detail while the right hemisphere attends more globally. It’s rather like a woodpecker pecking an insect out of the tree while at the same time keeping an eye out for predators. In photography, you could say that having a good grasp of detail allows you to master the technical aspects while seeing the connections between things makes meaning.
Understanding depth of field
An important concept in photography, depth of field(DoF) is simply the distance around the focus point that is sharp, in front or behind it. The depth of field can be controlled by:
Aperture – Aperture is the opening in your lens that controls the light coming on to the sensor. A wider aperture, say f2.8, will allow more light to come into the camera and will give you a shallower depth of field. A narrower aperture, say f/16, will allow less light to come into the camera and result in a larger depth of field.
Camera-Subject Distance – The closer you are to your subject, the shallower depth of field will be achieved, and the farther you are from it, a larger depth of field. of the lens. This is also true to some extent with the focal length of your lens. The more zoomed-in you are to your subject the shallower the depth of field will be as compared to when you zoom out or get a wider field of view, the longer will be the depth of field.
Focal-length of the lens – The capability of a lens to magnify the image of a distant subject is referred to as focal length. It can get technical but simply put, the longer you set your focal length the shallower the depth of field and smaller your focal length, the larger the depth of field.
Finding the “woodpecker” location was a little tough as all the large open ares in my house either have cemented walls or balconies with a glass in front. The only open one is in my studio on the 19th floor with almost my size tiny balconies. That meant that I had to use a smaller lens. All the images are made on the Canon 1DX Mark III and Canon EF24-70mm f/2.8. The camera was set up on a tripod. In the first set, I have cropped the top and bottom to focus just on the opening. The second set has the uncropped images. So here are the results.
The First Set
In the first image, the focus is just on the opening and the background is completely blurred out. In the second image, the focus is on the scene outside and the opening is blurred out. In the third image, this is the best depth of field I could achieve as the closest point of focus in too close. If I move a little back, it gets better but then the area in focus becomes too large and busy. Still, it gives a reasonable or acceptable depth of field and gives you the basic idea of how aperture works in creating a point of focus and how you can control the aperture to create varying depth of field in your images.
The Second Set
1. In the first scenario, what happens is that when the point of focus is close to the camera and you choose a wide aperture, like f2.8, it allows the maximum light into the camera, and results in a shallow depth of field, allowing the closest point to the camera to be in focus while blurring the background completely.
2. In the second scenario, the point of focus has now been changed from the closest point to infinity, keeping the aperture still at f/2.8, it results in greater depth of field but blurring out the nearest point completely out of focus.
3. In the final scenario, what has been achieved is a reasonable depth of field (not an extremely sharp focus at the closest point, yet reasonably acceptable), keeping both the background and the foreground in focus. The closest point here cannot be in complete focus as its too close a distance but if this distance is a little far, acceptable depth of field can be achieved.
Disclaimer: The closest point of focus (the first images in both the sets) is not the moon’s surface but the pigeon infested buildings and since I feed them, the railings are buried under pigeon-shit despite them being cleaned everyday. The textures are just created by the accumulated and stubborn shit that has over the years refused to be cleaned and have now become a permanent fixture. Feel free to get inspired for your next texture based exercise. 🙂
To achieve wider depth of field
- Narrow the aperture (larger f-stop like f16)
- Increase the distance from the subject
- Shorten focal length
To achieve shallow depth of field
- Widen the aperture (smaller f-stop like f2.8)
- Get closer to the subject
- Lengthen focal length
Berkenfield, D., Black, D., Corrado, M. and Silverman, L. (2020) Focal Length | Understanding Camera Zoom & Lens Focal Length | Nikon. At: https://www.nikonusa.com/en/learn-and-explore/a/tips-and-techniques/understanding-focal-length.html (Accessed 16/05/2020).
Burns, L. (2020) The Secret Setting: Aperture Priority Mode – Learn Photography | The Wandering Lens – Travel Photography Guides. At: https://www.thewanderinglens.com/learn-photography-aperture-priority/> (Accessed 15/05/2020).
De Leon, K. (2020) Why Aperture Priority Is The Most Preferred Shooting Mode By Photographers | Light Stalking. At: https://www.lightstalking.com/aperture-priority-most-preferred-shooting-mode-by-photographers/ (Accessed 16/052020).
Gray, E., (2020). Understanding Depth Of Field – A Beginner’s Guide | Photography Life. At: https://photographylife.com/what-is-depth-of-field (Accessed 17/052020).
Imaging.nikon.com. (2020) Nikon | Imaging Products | DSLR Camera Basics | Focal Length And Angle Of View. At: https://imaging.nikon.com/lineup/dslr/basics/19/01.htm (Accessed 17/052020).
Wunderlich, B. (2014) Understanding Depth Of Field For Beginners | Digital Photography School. At: https://digital-photography-school.com/understanding-depth-field-beginners/ (Accessed 15/05/2020).