Focus Stacking Detractors
Like many new and unpolished techniques, focus stacking has its
detractors. It just rubs some folks the wrong way. And the learning
curve with stacking focus produces some very bad examples and
that is mostly what we see online. I sure am guilty of posting
stacked photos with tons of artifacts so I understand why they may
not appeal. This technique is still new to the world. On the other
hand, well done stacked photos can be breathtakingly fine.
Focus stacking (like HDR and the various forms of stitching photos)
is still in its infancy and bringing up the rear at least with the
mainstream audience. Give it a few years and focus stacking will
emerge as what it intrinsically is, a brilliant form of impressionistic
photography.
Increments
I use the lens barrel to focus incrementally. You can use a focus rail
to control your increments between layers and there is even an
automated focus rail that can be programmed to exactly measure
and move the camera between shots. That is more than I want to
fiddle with so I am content just moving the lens a bit manually for
each photo. For me one important quality of any lens I use is
having a long focus throw. Those lenses with a very short focus
throw don’t give you enough distance to turn the lens. My favorite
macro lens offers almost 720 degrees of focus throw, more than
enough for me to tweak a turn of just a little bit.
I turn the lens just a tiny bit, especially if I am on an area of the
subject that I want to be especially sharp. I turn the lens and then
press to put the mirror up into lock position. Mirror lockup is
essential for me in focus stacking. Lock the mirror up and wait for
the shock of the mirror slap to die away. Then take the shot.
Doing this ten or twenty times per photo takes coordination and
time. It does not help to lock the mirror up, take the photo, and then
wait. You need to lock the mirror, wait, and then take the photo. I
find that I can turn the lens just enough to build a good stack,
increment by increment.
Tripod
Yes, you need a tripod. There are focus stackers who stack photos
handheld but they are like the showoffs riding their bikes and