I have to admit, I was not present for class during week three. Despite this unfortunate circumstance, I asked my peers what was learnt during that class. The focus of that day was ‘controlling depth of field’. Using my current knowledge through life experience, the first two weeks of classes and experimentation I shall explore the topic of ‘depth of field’ in this blog post.

What have I learnt in class that is related to ‘depth of field’?

1. The longer the focal length; the higher the potential for shallow depth of field
2. The wider the aperture; the shallower the depth of field
3. The closer the subject is to the camera: the shallower the depth of field
4. The bigger the camera the sensor; the higher the potential for shallow depth of field

Using my camera equipment, I decided to conduct an experiment that proves three out of the four points. I only have one camera, so that prevents me from proving the point about camera sensor size having an influence on depth of field. I conducted this experiment using a sauce bottle on a dinner table with a camera and tripod set up.

Point 1:

To demonstrate the first point, which refers to focal length, I took two photos with two different focal lengths (85mm and 28mm) using the same aperture and an almost similar field of view.

Shot taken on the 85mm

Shot taken on the 28mm

Point 2:

As you can see, the objects in the background of the 28mm shot are much more distinguishable compared to the shot using the 85mm.

For the second point, which refers to the aperture, I took three shots with different aperture settings with a fixed distance between the camera and the object.

Shot at f/2

Shot at f/4

Shot at f/8

Judging from the three photos, the the sauce bottle becomes less separated from the background. The objects in the background become more defined as close down the aperture because the depth of field becomes greater (less shallow).

Point 3:

Using the 85mm focal length, again, I took two shots the sauce bottle at two different positions. One shot had the sauce bottle close to the camera, whilst the other had the bottle further the way. The aperture, position and focal length of the camera were the same in both shots.

Shot with the object close to the camera

Shot with the object further away from the camera

The depth of field is significantly a lot more shallow in the first shot in comparison to second.

Conclusion:

In manipulating the distance of subject, changing the aperture and focal length we can change the depth of field. Knowledge of these three things will allow us to control the depth of field in the shot in order to achieve a particular look.