There's a method to the
all seen photographs of exotic peppers... the ones
you've always wanted to taste or grow for yourself,
but chances are you've never seen an x-ray or CT or
MRI scan of one. What I strive to do is to bring out
the the previously unsuspected beauty found in the
seemingly ordinary pepper pod.
be an extreme closeup photograph of a seed attached
to the wall of a pod, or a CT scan demonstrating the
delicate vascular bundles within the walls of the
pepper which once brought it water and nutrients.
Sometimes the technology that goes into creating the
image is as interesting as the images themselves.
For those of you who are unfamiliar with the methods
I choose to use I include a brief explanation of
each of the techniques I've used thus far. While I
do not currently have images to show from every
method (I've still got some surprises in the works)
I describe four of them here.
I'm sure you
are familiar with how a camera works... A
lens focuses the light reflected from an
object onto the film or digital sensor and
am image is created. The more light that is
reflected from the object's surface, the
brighter it appears in the final image.
radiography, a bean of radiation is passed
through the object being examined and the
rays that are not stopped by the object
create the image on the film or digital
detector. The more dense parts of the object
stop more x-rays from passing through and so
create a shadow.
difference between photography and
radiography is that rather than seeing
things as they appear to the eye (like a
photograph) an x-ray shows the structure
inside the object. If an object contains
items that are more dense than the majority
of the subject (like metal, or in our case,
seeds) they show up more brightly on the
A CT scan is
based upon x-ray technology so it too shows
the densities within the pod, revealing the
inner, hidden structures.
itself consists of taking a number of x-rays
from many different angles and then, using a
computer, plotting the various densities to
determine the 3-dimensional placement of the
internal structures. After the scan is
completed, the accumulated data can be
reformatted to create images of thin slices
of the object being examined.
It's as if
you took a pepper pod and sliced it into
thin (1 millimeter or less) slices, starting
at one end and going all the way to the
other, and then taking an x-ray of each
individual slice, often just a millimeter in
thickness. By doing a computer
reconstruction it's possible to slice that
pepper at any angle you want, put it back
together again, and start slicing all over
again in a different direction.
An MRI scan
does not use radiation like the radiograph
or CT scan. It uses an extremely high
powered magnet. The magnetic field aligns
all the protons within the hydrogen
atoms in the object (it works best with
subjects that contain lots of water) and
then sends a radio-wave pulse through the
object. This scrambles the proton alignment.
then computes the time it takes for the
magnet to realign the atoms again. Using
this measurement it is possible to determine
the chemical makeup of the subject.
in the CT scanner, all the information
obtained can be used to recreate slices of
the pepper in any direction . The difference
between the results of the MRI and that of
the CT scan is that the MRI can be used to
look at the function of the subject, not
just the structure. Using an entire plant,
the MRI scan can look at plant metabolism
and actually measure the amounts of
nutrients being metabolized during growth
and fruit maturation.
(Click on image for larger view)