Project 10

Focal Lengths and different viewpoints 

This project examines the difference made by taking the same shot, but with different focal lengths, and the effect it has on perspective.

I started by finding a suitable subject that I could photograph using the same viewpoint, but where I could move forward to the subject as I altered the focal length of the camera. (Moving forward was necessary to continue to fill the frame with the subject as the focal length changed.)

Notice on this first shot, at focal length 300mm, the relationship between the barn, the wall in front, and in particular, the distance there seems to between each and the barn.

What has happened is that the zoom lens has “squeezed” the distance so that both the tree and the front wall appear quite close to the barn.

As I moved in to the subject and changed the focal length to 210mm, the barn remain the same size, but the tree has got smaller, and the wall slightly bigger. 

Moving in closer still, using a focal length of 85mm, the barn is still the same size, but the tree has got much smaller, and the wall slightly bigger. The reason that the tree and wall are not changing size at the same rate is because the actual distance between them and the barn is not the same amount. The tree is actually further from the barn, and therefore the perspective changes at a different rate.

The final shot, at 40mm, still shows the barn at the same size, but now notice the wall. The front edge of the wall looks much close to the camera than the barn. The tree is now not visible, because as I got closer, the tree gradually receded behind the barn.