When I first started writing this I thought that technically it is very easy to control the depth of field of a photograph – just adjust the aperture and the depth of field will change. However, what I thought was the case turned out to be only part of the story! DoF is controlled by the length of the lens, and then the aperture may be adjusted within the limitations of a lens. So the longer the lens the deeper the DoF, and the shorter the lens, the shallower the DoF. Now I understand why my 100mm macro lens will only create images with a very shallow depth of field, nothing to do with the aperture, it is the length of the lens.
So, the question is when and why should the different depths of field be used when creating an image, and how does this affect the way an image is perceived.
Wim Wenders said “the most political decision you make is where you direct people’s eyes”. (Quoted in the OCA EYV course text).
As the dept of field affects the areas of the image which are in focus it can be used to direct people’s eyes. A deep depth of field will bring the whole image into focus leaving the eye to move around the image without any specific direction. A shallow depth of field will result in one small area of the image in focus and the background blurred. The eye will naturally be drawn to the small area and ignore the rest.
Ansell Adams created images which were sharp and wholly in focus, a move away from the Pictorialism (contrived images) toward Modernism. He wanted the whole image to be sharp and real – as it really is, not contrived. The benefits of looking at an image with great depth of field and focus is that it viewer can explore the image in their own way. There is no prescribed direction.
Fay Godwin set out to create a series of images which highlighted the amount of open space which was inaccessible to the ordinary person. She wanted the whole image to be in focus to give the feeling of space, and created them using a deep depth of field.
Alternatively, the use of shallow depth of field will draw the eye to the area in focus. In his series Panem et Circenses, Gianluca Cosci created a set of images with a shallow depth of field. He used this technique to make sense of the urban space around London, drawing the eye to the minutia, leaving the background blurred. Below is an extract of an interview with Kevin Byrne in April 2016.
“After moving to London from Bologna I had a kind of cultural shock especially regarding the city and its role as world capital. We could say that I was totally overwhelmed and quite intimidated by it. Everything exuded confidence, authority and superiority: economically, culturally and politically. Even the sheer size of everything was something quite difficult to deal with. I was fascinated and repulsed in equal measure by corporate places like the City of London or Canary Wharf with their obscene wealth and tangible power. The cultural institutions in the capital were no less confident in their self-awareness of prestige and influence on the world’s stage and the majority of people in that environment seemed to reflect all of this. My work during that moment was largely based on that feeling of being an outsider, an alien who observes things from a distance, unseen.”
Kim Kirkpatrick, on the other hand, was more focussed on the beauty around him, rather than a political statement. He created images with a shallow depth of field to highlight the beauty and colour which often goes unnoticed. In his early work he focussed on industrial waste sites, and the small things we don’t see.
The subject, as it always has been, is color and our daily environment – the results of constant searching for unnoticed elements of beauty and hidden, subtle significance in our surroundings. (Extract from http://www.kimkirkpatrick.com/)
Images using a macro lens are created with a shallow depth of field. The eye is drawn into the item being magnified, and the background blurred and to retain the detail of the background would detract from the subject. I have included 2 images I took with my 100mm macro lens, both showing that the background would not have enhanced the subject.