Use Of Differential Focus To Get Best Creative Macro Pictures

Utilizing Selective Or Differential Focus

Selective Or Differential focus  is a technique used in photography  through which special lenses are used to create focus layers utilizing depth of field information.It can pop out a subject from the rest or can isolate different portions of the same subject which attract a viewers eye to it, and it also creates a three dimensional look to the images with isolated interesting points.

To achieve that effect you must be aware of the concept of depth of field in photography. Differential focus can be achieved by focusing subject of interest in the image by controlling the depth of field. That object may be a nearer one or faraway. That effect is mostly achieved in sports and portrait photography to pop up the main subject and make the composition more simple by reducing the clutter. For this purpose mostly tele photo lenses at wide aperture are used.  Here in this short article I will try to tell how this effect works in macro photography. Macro pictures with limited zones of sharp focus and most diffused details are appreciated by those who love fine art macro photography. Differential focus can be achieved by using some Photoshop  plugins but not an alternative to the genius work with an appropriate lens. For this shot I used as an example here, Canon 60mm EFS lens is used at 2.8 aperture. Macro lenses have a shallow depth of field as an inherent property. Lenses with longer focal length like Canon 100 mm f /2 macro or Sigma 150 mm f/2.8 are more suitable to get extreme creative results.

When shooting insects, always try to keep the eyes of the subject in sharp focus and let the other scene get natural gradient in focus. Anthers of the flowers are another part in popular macro subject which is appropriate for differential focus. Here in this example I was lucky enough to have both, eye of the butterfly and anthers of the flower in the same plane which helped to keep  both in focus. Antennae and bristles of the butterfly are impossible to keep in focus when you are using shallow depth of field . So never mind and let the elements blur naturally and gradually. If you are able to create a soft illusive effect in the overall image then it would be a great macro work. Here  are the key points repeated again to keep in mind while shooting macro subjects:

* Use a macro lens with wide aperture

* Use these lenses at maximum aperture like f/2.8 or lower if your lens allow.

* Keep the eyes of the subjects in focus and forget about the rest

* If you are shooting a tree branch in spring then keep most prominent bud in focus.

* While using differential focus for flowers either focus on stamens and anthers in the middle of the flower or the outer most petal   and let the other flower blur naturally and gradually.