The Holy Trinity of Depth of Field

THE HOLY TRINITY OF DEPTH OF FIELD

Depth-of-field is an expanding and contracting field depending upon 3 equally important factors you can control. Don’t think ‘better‘ or ‘worse‘ think ‘more‘ or ‘less‘ and you use your judgment, taste and style applied according to what the image or subject needs or even wants to determine how much is best.

These 3 factors are interrelated to create depth-of-field:

1) Aperture:
– Smaller aperture/smaller opening (towards f16) gives more depth of field
– Larger aperture/bigger opening (towards f2.8) gives less depth of field

2) Focal Length of Lens
– Shorter lens/wide angle/zooming out gives more depth of field

– Longer lens/telephoto/zooming in gives less depth of field

3) Distance to Subject
– Closer to subject gives less depth of field

– Farther from subject gives more depth of field 

 

Distribution of focus:
1/3 in front of focus point, 2/3 behind

In general practice, focus on the closest object you want in focus and choose an aperture to expand focus to the furthest object you want in focus.

For critical focus, focus 1/3 into the area you want in focus and use aperture to get the depth of field you want.

Also:
– The smaller the film format or the smaller digital sensor (like in point and shoots) the greater the depth-of-field.

– The larger the film format or the larger the digital sensor the less the depth-of-field.

 

©Douglas Beasley 2014