I started
shooting macros 3 years ago with a point and shoot digital.
I am still at it. I remember my disappointment in not being
able to fill the screen with the object I was interested
in. So I tried (and continue to have fun with) diopters.
As soon as I started with the diopters, I noticed that the
DOF issue was becoming more difficult. The more magnification
I used, the less DOF was available. Then I discovered using
a 50mm lens in the reverse position for extreme macros.
I just love the technique, but at this level of magnification,
the DOF is paper-thin.
While
I seem to have the ability to nail the focus on the eyes
of a tiny insect, the results of a single image are often
less than satisfying. For example, with a head on shot of
a fly, you can get the eyes in focus, but then the nose
will be out of focus and vice versa. For side profile portrait
of a damsel, you can get either the eye or the face in focus,
but not both.
I had
read an article by Fred Miranda where he had combined two
exposures of the same scene to gain a better tonal range.
This gave me the idea to combine two images of the same
scene that differ in the plane of focus in an effort to
increase DOF. Each of the images in the gallery that accompanies
this article was created in this manner. Although it is
not easy to do and requires lots of practice, I am pleased
with the technique. If you want more DOF than your camera
gives and your comfortable in the digital darkroom, give
the technique a try.
For
the technique to work, you have to keep it in mind when
shooting. For example, take a shot of a fly with the eyes
in focus and then move the camera back a tad and get the
same shot with the nose in focus. While I use Photoshop
7, any high-end image editor should work. One image serves
as the main image, for example the eyes. Then I carefully
select the nose from another frame (usually the next frame
I shot). If I am lucky, I might even get a third shot with
the portion of the back of the fly behind the eyes in focus.
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When
selecting the more in focus feature of the critter to add
to the main image, I make sure to select more than I need
and then feather the selection before copying it and pasting
it into the main image. It will be a new layer. It is important
that the two frames involved be as identical as possible
except for the plain of focus. This is difficult to do considering
that the majority of my shots are handheld. Sometimes the
feature (e.g., nose) doesn't fit quite right. You need to
reshape it so that it does. This involves subtle adjustments
such as skewing and resizing using the transform tool. (If
the adjustments are not subtle, the two images are too different
for the technique to work well.) After the feature fits
nicely, begin to erase the edges so that they blend in to
the primary image to the point where no one would notice
that two images are involved. This may take some blurring
of the edges as well as use of the patch and cloning tools
in various ways. When you are happy with the blending, flatten
the image and clean up the edges some more. Then begin to
adjust levels, contrast, saturation, sharpness, etc. as
you normally would for a digital negative.
All
text and images copyright Mark Plonsky 2003. All rights
reserved.
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