This exercise involves finding a subject in front of a background with depth and taking two shots from a close viewpoint and using the same focal length. The first photograph should focus on the near object, and the second should be focused to infinity.
This is my first image, focused on the grass in the foreground:
My second photograph is focused on the boats in the distance:
This exercise shows that the depth of field is narrower when the subject is close to the camera. The further away from the subject, the deeper the depth of field.
In this case, I prefer the first image although the depth of field is so narrow as to almost totally obscure the background. The eyes are drawn to the grasses since they form the clearest part of the image and it is actually quite hard to tell what is in the distance. However, there is a sense of the background being a deliberate composition because it looks quite pretty. I think I like this image because the colours work nicely, (blue and yellow are opposites on the colour wheel and therefore harmonious) and the out-of-focus masts seem to add an abstract effect that is quite appealing. However, for this shot to be more successful, I think the grasses would need to be more interesting as a subject.
It is clear in the second image that the boats are the subject. The eye is initially drawn to the yellow boat and then to the others, and on to the masts. I am not sure that the grass adds anything at all to this image, though it perhaps helps to add a feeling of depth. The grass is so blurred that it probably confuses the viewer who may be unable to tell what it is. Had the grasses been more substantial, or I had used flowers instead that were more obvious, this may have added something to the image.