After posting this photo of Mystic Seaport employee, Sam, to the group I was asked by another member regarding the settings used to get this particular look. I thought I'd share and elaborate on my response.
However, with that being said the numbers do give clues to other aspects of the image. This shot was taken at 1/80th of a second at f/8 and an ISO of 1600 with a focal length of 24mm and the camera on a tripod set on aperture priority. First we see that the image is shot in a location with a shadowed background. A low ISO would mean having to shoot with a long exposure. That wouldn't do in capturing a person since movement is a concern. Remember that the shutter speed needs to be at or higher than your focal length to avoid blur. My camera was on a tripod only because I was shooting for HDR at this location, not because I wanted this portrait. The portrait was just an opportunity that presented itself while I was there.
The next item of interest is the aperture. At f/8 it lets you know that I was looking to capture a certain amount of detail in the background. This is an environmental portrait so placing the subject in his environment was key to describing his occupation. I could have gone with other aperture settings but I felt this to be the best. Anything above f/8 would have brought out more detail that, in my opinion, would not have added anything to the portrait. A larger opening would have given me a shallower focal length but I wasn't interested in a blurry background for the reason I stated earlier.
Although I talk about settings in this post first they actually came last in the process of this capture. I was with a group of people listening to Sam (the cooper) talk about the art of coopering and was totally fascinated by the conversation. As I was listening I saw how the light coming in through the door fell stronger on Sam than on the background. The light in his workshop was gorgeous, giving the various barrels, casks and pails a warm glow. That was in sharp contrast to Sam's blue work outfit. This is when the thought of getting his portrait came to me.
At this time it was simply a matter of waiting for my opportunity to have Sam pose. I actually had to interrupt a visitor and ask for a few minutes time to take the portrait. Once Sam gave me the go ahead I placed his tools in his hands, asked him to stand where I wanted him to and fired away.
This whole shot was done in two exposures, a preliminary setup shot and the final portrait. I thought about doing another shot of him without smiling but dismissed it as I didn't want to hog his time. The last part was a formality of sharing information for me to send him a copy and I was done. I got a great capture and he gets a great portrait.
* Pat Cook's group, Beyond the Photo with HDR, has dissolved and is no longer available.