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50
Ways To Lose Your
Data
Before
I answer your questions,
I want to touch on
a topic I’ve
mentioned before—but
one whose importance
I can’t stress
enough: backup! Image
file sizes are getting
bigger, storage mediums
are carrying more
data, and all of
this leads to the
potential of catastrophic
failures.
A good friend of
mine recently had
the hard drive on
his laptop fail.
No amount of cajoling
could revive it.
This was his main
image-editing computer.
Although he had been
following my advice
of regular backups,
there’s one
thing that was still
missing: he assumed
his backup process
was working prop-erly.
He didn’t test
to make sure that
if something went
wrong with his online
data, he could readily
access his offline
backup.
It turns out that
his regular backup
routine was only
backing up some of
his files. He ended
up having to contract
with a data recovery
company to restore
his files. In this
case, it was to the
tune of more than
$1,000, and even
then, several critical
files were gone.
For some people,
there’s the
thought that “It
won’t happen
to me!”, but
in reality, I think
it’s a matter
of when it will happen,
not if it will happen.
I’ve mentioned
a little envisioning
exercise before:
next time you sit
down at your computer,
close your eyes,
wait a few seconds,
then open them and
imagine that your
hard drive has been
completely wiped
out. What would you
do? What did you
lose? How important
is that data?
Then, check to see
if your backup is
working properly.
Try to recall important
files, open them
up in your image
editor and verify
that they haven’t
been corrupted. Bottom
line: if you value
your images, you
should evaluate your
backup system.
Stuck
On Auto
I’ve
been enjoying my new
digital camera. I’ve
learned about histograms,
flash and focus, and
even a bit about composition,
but I struggle with
shooting modes. When
it comes down to taking
pictures, I fall into
automatic mode all
of the time. There
are two settings that
I’m trying to
learn: aperture priority
and shutter priority.
When should I be using
them?
It’s
great that you’re
reading the manual
and trying, and the
fact that you understand
histograms will help
you even more (the
histogram sometimes
can be more difficult
for people to understand
than aperture priority).
First, let’s
review the basics
so we can understand
what these settings
do. You control the
amount of light reaching
the image sensor
through two basic
adjustments: aperture
and shutter speed.
Aperture controls
a diaphragm in the
lens that’s
similar to the iris
in your eye. By opening
and closing this
diaphragm, you restrict
the amount of light
hitting the image
sensor. The bigger
the opening, the
more light is let
in. Aperture is measured
in ƒ-stops,
which represent a
fraction, so the
larger the ƒ-stop
number, the smaller
the opening.
The shutter is a
mechanism for controlling
how long the light
passing through the
aperture is allowed
to land on the image
sensor. The longer
the shutter is open,
the more light that
lands on the sensor.
Shutter timing is
shutter speed and
is measured in fractions
of a second (or seconds
for long exposures).
These two settings
are calibrated in
cameras to allow
you to easily control
your exposure. For
example, if you want
to increase your
shutter speed by
one step, you’d
need to decrease
your ƒ-stop
by one step.
When you’re
using aperture or
shutter priority,
you’re using
your camera’s
auto exposure mode;
however, you’re
telling the camera
that you want to
pick one of the exposure
settings and let
the camera, in combination
with the light meter,
choose the setting
for the other parameter.
For example, you
might set the camera
to shutter priority
(Tv or S) and choose
a shutter speed of
1⁄125 sec.
In this case, the
camera will always
take the picture
at 1⁄125 sec.,
but the aperture
will vary, depending
on how the light
meter reads the scene.
Conversely, if you
choose aperture priority
(Av or A) and set
the camera at ƒ/8,
the camera will adjust
the shutter speed
to the proper setting
as guided by the
meter.
Why pick one over
the other? Because
aperture and shutter
speed don’t
control just exposure;
they also control
the look of the image.
If you choose a fast
shutter speed like
1⁄500 sec.,
you’ll stop
action in your scene.
So if you’re
shooting sporting
events, you might
want to set your
camera to shutter
priority, use a fast
shutter speed and
freeze all of the
motion in your photos.
Or you might want
the action blurred,
so you’d force
the camera to stay
at 1⁄60 sec.
(or longer). If you
choose this mode
when shooting water
scenes and set the
speed to a 1⁄2
sec. or longer, you’ll
get that “smooth,
blurred water” look.
Choose aperture priority
when you want to
affect depth of field.
Depth of field is
the range of distance
from foreground to
background where
the image is in focus.
If you set the aperture
to a small opening,
like ƒ/4, the
range of objects
that appear to be
in focus will be
shallow, with the
subject and little
else in focus. If
you close down the
iris to ƒ/11,
the range of sharpness
will increase to
include much more
than your subject.
Aperture priority,
then, helps to control
the depth of field.
If you’re shooting
someone outside with
a busy background,
you might want to
have a shallow depth
of field so that
the background goes
out of focus and
becomes less distracting.
Conversely, you might
be taking nature
photographs where
you want both foreground
objects and the mountains
in the background
to be in focus. In
that case, you’d
want a large depth
of field. Since you
probably wouldn’t
be too concerned
about shutter speed,
the Av setting would
work well.
In short, aperture
and shutter priority
really allow you
to take more control
of your camera’s
auto-exposure capability.
From Film To
Video
Years
ago, I converted
old 8mm movies to
8mm videotape by
projecting to a converter
box and taping with
a video camera. I’d
like to convert the
film again with better
quality by scanning
the film digitally.
Does anyone make
a scanner that converts
8mm movie film to
a digital video file?
|
Joe Cuomo
Monkton, Maryland
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There
isn’t
an 8mm scanner available,
unfortunately—or
at least one that
would be available
on a retail basis.
If you think about
the differences in
size between a 35mm
negative and an 8mm
motion picture frame,
you can see that
8mm is just a fraction
of the still image
size. Size difference
aside, think of how
long it takes to
scan one 35mm transparency.
Now imagine scanning
multiple frames—maybe
as many as 18 frames
per second—and
you can see how the
requirements of an
8mm scanner would
be a tall order.
Now, one could argue
that with 8mm, you
wouldn’t need
the resolution requirements
of a 35mm scanner.
Since you’d
probably output to
traditional video
devices, their pixel
count is 720 x 486
for NTSC (the North
American television
standard) or 720
x 576 for PAL. (If
you’re used
to thinking in terms
of dpi or ppi, think “less
than 100 ppi.”)
There’s one
more piece to the
equation, however:
each frame that was
placed in the scanner
would have to match
the exact position
of the previous frame.
If any frames aren’t
positioned properly,
there would be a
very distracting “film
weave” as each
frame of film jumps
around when displayed
in sequence. This
isn’t a feature
of current transparency
scanners.
If you have the money,
there are professional
film scanners called
telecines that are
used for motion-picture
transfers. They’re
expensive (well over
$100,000), however,
and many don’t
have an 8mm “gate” for
transferring that
size film.
Another option is
to call a film transfer
company to see if
its telecine has
an 8mm gate. In my
experience, the charge
for transfer would
be several hundred
dollars per hour.
There are many small
labs that advertise
the transfer of film
to video, however.
Check out what’s
available in your
area and give one
a test to see what
they can do.
If you have any questions, please send them to HelpLine, PCPhoto
Magazine, 12121 Wilshire Blvd., Ste. 1200, Los Angeles, CA 90025 or
[email protected].Visit
our Website at www.pcphotomag.com
for past HelpLine columns.
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