Focus Stacking
Interest in ‘focus stacking’ is increasing rapidly. In this short article I
would like to suggest some reasons why this might be. For those of
you unfamiliar with focus stacking, let’s make clear what it is.
Just as exposure bracketing and HDR (High Dynamic Range),
techniques (where a number of photos are taken at different
exposures and then seamlessly combined into a final photograph)
are popular so focus stacking takes a series of photos of an object
each taken at slightly different focus points and combines these
photos seamlessly into a final photo that represents the object with
everything in focus, as if it naturally had greater depth of field
(DOF).
Focus Stacking is essentially ‘focus bracketing’ and the result is a
photo where everything (or more than you might expect) appears to
be in focus as opposed to the traditional photograph where there is
only a single point of focus and anything not at the point is to some
degree out of focus, however slightly. The resulting stacked photo
(from combining the images at different focal distances) can be
remarkable and advances in software like Zerene Stacker, Helicon
Focus, Adobe’s Photoshop CS4 are perfecting this technique.
Two Types of Focus Stacking
There are two general types of focus stacking being used today
with perhaps the most common idea of this technique including a
camera mounted on a focusing rail (or a lens with bellows attached)
and the photographer taking many dozens (sometimes up to 150-
200) photographs, each photo just a few millimeters apart from one
another. This first technique is used mostly for scientific, product
photography, and by a few naturalists who carefully create deep
stacks, usually in a studio, like the one a few pages down, which is
very interesting.
And while this more elaborate form of focus stacking is wonderful in
its own way it requires more specialized equipment and does not
readily lend itself to being used outside in the fields and woods or at
least is more difficult to take outside. There are many tutorials on
the web for this more technical type or style of focus stacking
available so I refer you to Google to find those. For myself, I am not
much interested in that method because I don’t want to haul all that