The above photo is titled “Veteran with a Flag”. It is by Diane Arbus and was shot in New York City in 1971. I chose this photo for my example of short depth of field because of how the man is in much sharper focus than the rest of the photograph. You can see very clearly the details on the man in the front of the photo because of how sharp the focus is on him. The woman behind him is more blurred and the walkway and buildings behind him are even more blurry. The depth of field along with the fact that this photo is in black and white creates a nice contrast between the blurred lightness of the walkway and buildings and the sharp dark aspects of the mans suit. As I analyze the composition of the photo further I see that both the facial expression of the man and the American flag are accentuated by the depth of field and the contrast between the light and dark of the background. Having the face so close to the light part of the background really allows for the audience to focus on it. Furthermore, since the detailed American flag is against a very solid dark part of the photo the audience can also view it very easily. Overall, the depth of field contributes to the composition by sharping the aspects of the photo that the photographer wants the audience to focus on.
The photo above is titled “Chinstrap Penguins Dive off Icebergs Located Between Zavodovski and Viskoi Islands in the South Sandwich Island”. It is by SebastiĆ£o Salgado and was taken in 2009. I chose this photo as an example of long depth of field because of the sharpness of the entire photo. As I analyze this photograph I can see that the camera tries to focus on the entirety of the photo rather than something specific. This photo also is in black and white which allows for a contrast between the lightness of the iceberg and the darkness of the ocean. This creates a very pleasing landscape for this photo. The smoothness of the iceberg also contrasts nicely with the rough water that is right next to it. Furthermore, the penguins are darker and they are on a lighter surface which really draws attention to them and what they are doing. However, even though the photo is focused on the penguins, the depth of field also allows the audience to get a full idea of the scene that is being displayed.
Good observations of focus and light and clear understanding of depth of field in your examples.