Brief: Flash isn’t just useful to illuminate a dark scene, but to bring out a foreground subject with a flash that is balanced with ambient light – be that sunlight or artificial light. You can see many examples of fill-flash in Martin Parr’s photographs at www.martinparr.com You can use an on-camera flash or an external flash for this exercise. Take a subject – a person for example – and frame them against the sky. Make sure the sky is either a cloudy sky or the most intensely blue portion of the sky – on the opposite side from the sun. Put your camera into Manual mode and activate the flash. Flash units usually give you different strengths of flash output: minimum, medium and maximum, for example. You may want to experiment with these later, but for now use medium. Take a photograph of the subject and review it. Is the person’s face too bright and over-exposed? Is the background sky too dark? Now balance these two elements. At slower shutter speeds the background will become lighter. At fast shutter speeds, the background will be progressively underexposed (darker). To change the illumination on the subject use a combination of flash output and aperture (f-stop) to darken (close aperture) or lighten (open aperture) the foreground subject. The balance is achieved because the flash will illuminate the f/g subject by the same amount whatever the shutter speed. But the shutter speed will change the b/g.When you have a balance you like between the subject and the background, take a short series of pictures varying your position from close to distant. You’ll need to make adjustments to the aperture or flash output strength when you change the distance between you and the subject due to light fall-off.
This has not been easy for me to do for a couple of reasons. I don’t have any one to model for me, and I have not used flash before. It took several times of reading the brief, and my camera manual to understand how to use the flash. This is something that I will continue to practice.
The instructions in the brief are quite clear now that I have gone out to practice, but whilst doing so I found it tricky. I do find it awkward to ask people to model for me becuase of the anxiety that I experience, and I am not good at talking with people once I have asked them. Because of this I don’t think that I put people at ease. Maybe I am being a little hard on myself, there were some people who were easier to ask than others, and easier to talk to as well. In fact, those that agreed to have their portrait made are interested in my studies and become quite engaged. It wasn’t easy to remember whether I wanted to change the shutter speed or aperture or both, and whether I wanted to lighten or darken the background or the person. But its practice.
This gent was wonderful, relaxed, easy to talk with. I took a set of photos and we chatted for a while, he laughed, and this brought out the cheeky side to his character, so I re-shot him. He is my pick of the bunch.
This first series was practicing with changing the shutter speed to allow more background light in. I didn’t adjust the aperture because I wanted to see how shutter speed affects flash photography. The aperture was f7.1 for each photo, shutter speeds were 1/250, 1/125 and 1/80. These don’t work as photos, but if I had stepped down the aperture to f11 or slightly beyond then they would have been more correctly exposed.
The following were all 1/80 sec, and I changed the aperture so that it affected the amount of flash allowed through to the subject. By reducing the aperture size the background lighting is also reduced. The apertures were f11, f16 and f22.
This is the better photo. Better exposure, and more relaxed following the laughter. ISO 100, f22, 1/80.
For the next series, the first three photos were all f6.3, and the shutter speeds were 1/25, 1/60 and 1/160.
In the following the shutter speed was 1/160, and the aperture was f9 and then f13. I prefer her smile on the first photo (below) when compared with the above, although the exposure for her face is better in the third photo above. I think the first photo below would look good if I had shot it at f9 with a shutter speed of 1/100. All of the photos on this blog have been through Lightroom for camera and lens calibration and then exported to reduce size, with no further changes. I needed to explore and understand the effects of the technique rather than develop the photo.
One of the great benefits of fill flash is that you can reduce shadows and improve exposure, to gain a more balanced skin tone,when a person is lit from the side. For this set I adjusted the aperture and shutter speed to try to create balanced lighting. However, I didn’t account for the fact that a waiter was serving to the left of and behind me and this created different shadows in each photo. If I concentrate on the face then I am aware that although one side is more brightly lit, the shadow is reduced on the opposite side of his face when I have the exposure right. I am ignoring the middle photo with regard to balanced lighting on the face, as the shadow eliminates the side lighting. Data is:- f9 1/50, F9 1/100 and f13 1/100. The f13 in the third photo is better for the face, but the shutter speed could do with being a bit slower to lighten the background. The background is very distracting, however, he was sitting down having coffee with his wife, and I am very grateful that he allowed me to interrupt.
Having a subject back-lit can make it easy to create good subject exposure because the flash is the primary light source. That said, sun spot/flare and over exposed background then rear their ugly heads. For the next set I adjusted aperture and shutter speed to try to gain the correct exposure. f11 1/250, f9 1/160, f7.1 1/160 (photo three would work better with a darker background i.e. f7.1 1/250).
From reviewing these photos, it is noticable that the background lighting is gradually increased or reduced with changes to the shutter speed. With the altered aperture the increase or reduction is more significant. I need to practice this exercise frequently until I become accustomed to changing both aperture and shutter speed so that I can alter the foreground and background lighting in a manner that is appropriate for the scene I want to shoot and the effects I want to create.