Focal length is a vital tool in the armory of a portrait photographer. In formal portraiture, it can be the difference between flattering the subject and taking a shot that is distinctly un-flattering and never being asked back. This exercise required me to take a series of portraits. I needed to take them at different focal lengths, using the same subject, pose and framing. I took five frames at different focal lengths, taking care to frame each one as closely as possible to the last. As the focal length shortened so I walked towards the subject to retain the framing. The aim was to see what difference the focal length made to the final image and the way I approached taking each photograph.
In the images below I have kept the aperture and shutter speed as similar as possible in the images so that the viewer only need worry about is the focal length as we approach the subject. I have not edited the images so what the viewer sees is what was ‘in the camera’. The focal lengths given are full frame equivalents.
This was taken with my telephoto lens at maximum focal length (315mm). Focused on the eyes, the background is out of focus and foreshortened, centering the attention on the subject’s face. The light is soft and forgiving and the image is a pleasing likeness of the subject and well proportioned. I have shot on ISO 400 to prevent camera shake with the long lens. Therefore I have used this ISO throughout for continuity in the shots.
At a nominally shortened focal length, the overall appearance of the photograph is very similar to the last. The main difference is that of framing. In order to maintain the framing I have had to crouch slightly lower. This has the effect of bringing the background up behind the subject’s head.
This is the focal length favoured by many portrait photographers. The background is still out of focus creating a good ‘bokeh’. The eye-line is natural as are the facial features. It is a very forgiving focal length and gives good flexibility and control over image taking.
This focal length is another favoured by portrait photographers, often those working in the street photography genre. The background is now appearing at a natural distance away from the subject and has dropped significantly in the frame to retain composition continuity. In comparison to the first image in the series the subject’s features are becoming more pronounced, a little less forgiving and starker. This is why a street photographer will often choose this lens as it offers some realism within the frame whilst still being a long enough focal length not to distort the subject. It also means the photographer needs to be close in to the subject (I was about 3 feet away here) meaning the subject will more often than not (in a street scenario) be well aware that they are being photographed.
At a relatively wide angle (I have halved the focal length of the last image), I now appear to be shooting almost up, into the subject’s face to retain the composition of the frame. I can now fully see the underside of the shelter, which was only just coming in to frame in the previous image. The background as a whole is much less controllable and cluttered as a result. The features of the subjects face have now become markedly exaggerated. The appearance is starting to become that of looking in to a fish bowl and not very natural, especially in comparison to the previous image. The face appears wider and the shoulders slightly narrower by comparison. This gives the impression that the subject is leaning slightly in to the camera (which she is not), with the chin apparently leading.
As expected, the longer focal lengths give the most attractive results, flattening out the features and background to give a good likeness of the subject. I found this acceptable all the way up to the 52mm focal length (although the appearance is significantly different from the previous image at 82mm), but soon after this the wider angles start to change the way the subject and the environment looks quite radically.