The brief:
Find a location with good light for a portrait shot. Place your subject some distance in front of a simple background and select a wide aperture together with a moderately long focal length such as 100mm on a 35mm full-frame camera (about 65mm on a cropped-frame camera). Take a viewpoint about one and a half metres from your subject, allowing you to compose a headshot comfortably within the frame. Focus on the eyes and take the shot.
Wide apertures create shallow depth of field, especially when combined with a long focal length and a close viewpoint. In human vision the eye registers out-of-focus areas as vague or indistinct – we can’t look directly at the blur. But in a photograph, areas of soft focus can form a large part of the image surface so they need to be handled with just as much care as the main subject.
The Shot:
f1.4, 50mm, SS 1/60, ISO 320
I chose this shot as in my opinion it works best at a wide open aperture really blurring the background and helps to emphasise focus on the subject. At this aperture there is even noticeable loss of focus on the extremities of the woollen hat and coat. I confess by accident but i also really like the similarity between the motif on the hat and the blurred shape on the picture in the background, the similarity in colour, size and rough shape work well here.
Experimentation:
I experimented over different apertures using a small statue and with a photograph in the background to provide some interest. My aim being to see if i could subjectively discern between different levels of ‘out of focus’ in the background and it’s effect on the overall picture. Highly subjective I believe, in the images below the one that works best for me is at f8.0, unlike on the shot for this exercise where i think fully open aperture of f1.4 works best.
I noticed during this exercise a clear relationship between the f-stops and shutter speed. With shutter speed doubling on each f-stop reduction in aperture. I have been aware of this however this exercise helped bed in the relationship. I started this experiment in aperture priority mode which meant i paid little attention to shutter speed. This is my standard way of operating so far with my photography so could explain why i don’t really have a good feel for the relationships between f-stop and shutter speed. I had a lot of difficulty using aperture priority mode and achieving good exposure during this experiment however and switched to manual mode for the shots below.
I also noticed evidence of some dust on the camera sensor which becomes more evident as aperture is reduced, some cleaning to do.
f1.4, 50mm, SS 1/125s, ISO 100
f2.0, 50mm, SS 1/60s, ISO 100
f2.8, 50mm, SS 1/30s, ISO 100
f4.0, 50mm, SS 1/15s, ISO 100
f5.6, 50mm, SS 1/6s, ISO 100
f8.0, 50mm, SS 0.3s, ISO 100
f11, 50mm, SS 0.6s, ISO 100
f16, 50mm, SS 1.3s, ISO 100
DKL_OCA_ExpressingYourVision_LearningLog 