There are specific camera settings and equipment factors that influence sharpness of the subject and overall photograph. Get the most value from the camera’s focus functions by understanding and applying these tips:
Depth of Field
Depth of field is how much of a given photograph is in sharp focus, from front to back. Only the subject you are focused on is tack sharp. Other elements in front of and behind the subject will be somewhat sharp. The following factors control depth of field:
- Focal Length – A long lens (such as 300-600 mm) produces shallow depth of field. Telephoto lenses are great for wildlife portraits and showing detail.
Subject Distance – As you get closer to the subject, depth of field decreases down to fractions of an inch.
- Focus Point – Depth of field extends about one-third in front of the point you focus on, and two thirds behind it. Focus on the eye of the tiger and its nose will generally be in focus. When photographing an animal with a long face, such as a zebra or wolf, try to photograph their profile to ensure their eyes and nose are in sharp focus.
- Aperture (f-stop) – Small f/numbers such as f/4, produce limited depth of field. Large f/numbers such as f/22, increase the zone of acceptably sharp focus.
Auto Focus Mode
Cameras offer two types of auto focus modes, by which the camera focuses automatically when the shutter-release button is pressed halfway.
- Single Servo (S) – The auto focus function focuses when the shutter-release button is pressed halfway, locks and remains locked. Use this when the subject is not moving.
- Continuous Servo (C) or AI Servo Mode – The auto focus function focuses continuously while the shutter-release button is pressed halfway. If the subject moves, the camera will engage predictive focus tracking to predict the final distance to subject and adjust focus as necessary. For most wildlife photography, use Continuous Servo (AI Servo) mode.
Auto Focus Area Mode
Focus points are the little empty squares or dots that you see when you look through your viewfinder. The area of the frame that the camera will use for auto focus is shown by the focus points. Modes:
- Single Point or Manual AF Point – The camera uses one focus point that you choose in your viewfinder to acquire focus. Use Single Point Mode for the majority of wildlife photography, because it enables you to select a specific feature such as an animal’s eyes on which to focus.
- Dynamic Area or AF Point Expansion – You choose one focus point. Once focus is acquired, if your subject moves, the camera will utilize the surrounding focus points to track subject movement and keep the focus on your subject. Pan the camera along with the subject to make sure the subject stays close to the initially selected focus point.
Use Dynamic Area (or AF Point Expansion) and/or Predictive (3D) Tracking for wildlife that is running, flying or moving sporadically. To track a small portion of the scene, pick a small number of points (such as 9 points). To track the entire frame, pick the highest number of points available or predictive (3D) tracking to track your subject.