Ensure sharp focus
Top techniques for ensuring sharp bird captures
Compositional skills are pointless without a good understanding of focus; a badly focused image will be immediately rejected by picture editors and competition judges. Focus is not just about sharpness and can be used to enhance a subject. Make sure the most important or interesting element is in focus; with animals this will usually be the eyes.
The focal plane is the specific area upon which the lens is actually focused and therefore the distance from the camera at which the sharpest focus is attained. Essentially the focal plane is an imaginary line that runs across your image parallel to the camera’s sensor. Using a wide aperture (low f-number) reduces the depth of the plane and a narrow aperture (high f-number) increases it.
I used this knowledge to capture a kingfisher with a freshly caught fish on a No Fishing sign, ensuring that the bird, its prey, and the sign were in sharp focus. A bird’s feet and eyes often occupy the same focal plane, so by selecting an AF point over part of the sign I was able to set my focus and composition before the bird entered the scene. I selected a reasonably narrow aperture of f6.3 to increase the depth of the focal plane.
For most hide photography I will use a telephoto lens and autofocus in one-shot AF mode. I also typically only select a single autofocus point as I find this leads to more accurate focusing. Modern AF systems are superb but will still struggle in certain situations, like shooting towards the light or when there is a lack of contrast in the scene.
The focal length of the lens you use also affects the depth of field. A 300mm lens at f4.0 will have a much shallower DOF than a 100mm lens with the same aperture; assuming the subject distance is also the same. Using a camera/lens support will add stability, resulting in better focused images.
“Using a camera/lens support will add stability”