Understanding Depth of Field and Live View in Canon Rebel T6

Recently, a user posted about an issue with their Canon Rebel T6, where the live view image on their camera's screen shows a wire fence not in focus. However, when they take the picture, the fence ends up being in focus. This discrepancy can be attributed to the differences between live view and the final captured image, primarily due to the concept of depth of field.

Depth of Field in Photography

In photography, depth of field refers to the range of distance within a scene that appears sharply in focus from the front to the back of the image. The aperture setting on your camera's lens plays a critical role in determining the depth of field. The higher the f-number (aperture setting), the greater the depth of field. Conversely, a lower f-number results in a shallower depth of field, making specific parts of the image more or less in focus.

When you use live view on your Canon Rebel T6, the camera's LCD screen shows the frame with the lens aperture set to its widest opening. This means the image will appear bright, even in lower light conditions. However, when you actually take the photograph, the camera stops down to the aperture setting you have chosen. For example, if you are shooting with an aperture of f/2.8 in live view, the final image might be taken at f/11, which would increase the depth of field significantly.

The Role of Aperture and Viewfinder

The importance of the aperture setting becomes evident when considering the final exposure and the depth of field. In manual mode, the photographer sets the camera's functions, including shutter speed, ISO, and aperture, to determine the desired final exposure. The light meter helps the photographer understand the exposure settings necessary based on the ambient light, subject distance, and lens technique. It is crucial to pay close attention to the light meter in the viewfinder to ensure that the final exposure meets the photographer's intentions.

Factors Influencing Depth of Field

Several factors determine the final depth of field of a photograph:

Lens Focal Length: Wide-angle lenses generally have a wider depth of field, while telephoto lenses have a narrower depth of field. Aperture Setting: As mentioned, the higher the f-number, the greater the depth of field. Subject Distance: The closer the subject to the lens, the shallower the depth of field; conversely, the farther the subject, the deeper the depth of field.

The Canon Rebel T6 manual (refer to page 111) provides more detailed guidance on these factors. Understanding these elements is crucial to achieving the desired level of focus in your photographs.

Practical Tips for Shooting in Manual Mode

Shooting in manual mode on the Canon Rebel T6 offers great control and experimentation opportunities. However, it requires careful attention to detail:

Monitor Light Meter: Always check the light meter to ensure the exposure is correct. Test Shots: Take a few test shots to see how the depth of field and focus change with different aperture settings. Practice: Developing your skills in adjusting aperture, shutter speed, and ISO will improve your ability to achieve the desired effect.

By understanding the concept of depth of field and its relationship with live view, photographers can better control their shots and achieve the desired levels of sharpness and focus. Happy shooting, and remember to keep everything in focus!

Earl Langley
Have Camera, Will Travel