Here are a couple of images from a recent commission for Forwarder Magazine. The article featured Phil Denton, the managing director of Ital Logistics in north Manchester. My job on occasions like this is to create a variety of interesting portraits utilising whatever is on site. Generally, I take portable studio flash as well as a couple of speed lights in order to allow me to be able to control light, yet work quickly.
Portrait photography relies on controlled use of light to ensure an image really hits the mark. I this instance, I really wanted the backlit Ital Logistics panel to register an accurate exposure, but obviously I needed to keep the shutter speed at a realistically high level to avoid any possible blur. (Naturally, I was shooting from a tripod.) To work out the exposure, I start with the known values. I need to shoot at a shutter speed above 1/60th in order to be absolutely sure that no unwanted movement takes place. Ideally, I would like to shoot at f8, as this allows the lens to perform at or near it's optimum, and portraits always look good at f8. So, by altering the third and final control over exposure - the ISO - I can select the right sensitivity which will allow the sensor to record the exposure I need.
In this case the ISO was 800, which provokes no noise or other problems at all for my Canon EOS 5d Mark 111. This exposure records the back panel perfectly, now it is simply a matter of ensuring the light from the flash is also registering at f8 in order to marry the ambient and flash exposures. Simples.