FOCUS STACKING FOR MACRO PHOTOGRAPHY: A BEGINNER'S GUIDE

Depth of field, or DOF for short, is one of the most difficult aspects of macro photography.

- SANCHIT MISHRA

Not only does the sharpness zone decrease as we move closer to our targets, but additional issues like as low light and diffraction softening make using small apertures difficult. It is already hard to capture the entire picture in focus at a magnification ratio of 1:1 unless you are shooting your stamp collection, and it only gets worse as we increase the magnification ratio.

The DOF-Problem and its solution

As previously stated, this is due to the nature of optics: the closer a subject is to the lens, the shorter the depth of field will be. This may be mitigated by using a small aperture, which cancels out a substantial section of the light cone in order to reduce sharpness fall-off.

However, this only works to a limited extent. When the aperture opening becomes too small, light waves bend and soften the picture. This is referred to as diffraction. Fortunately, there is a method known as 'Focus Stacking' that allows us to go around this limitation by mixing many photos.

Focus stacking

Focus stacking is a method that involves taking many images of the same subject at slightly varied focussing distances and "stacking" them. When we combine these photographs in postproduction, we get one overall crisp image with the entire frame in focus. This strategy is popular among landscape photographers for getting both the foreground and distant background in focus, but it's especially effective for macro photography.

The fundamental concept is to set up your camera on a tripod, frame the scene, and then take a series of photographs with the focus moving slightly between shots.

There are a variety of methods for executing a focus stack, so let's have a look!