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Nikon 4500 macros


#1

I could really use some help taking macros of my work with a nikon
4500. I have read the manual several times and asked on a few photo
forums, and have still not gotten the desired results. The center
of my piece seems to be in focus while the edges are not. I am
using a cloud dome, and setting the camera in close up mode. I set
the camera on delayed shutter release so I don’t have to touch the
shutter. I also set up the piece close enough to the camera so it
fills up the frame to avoid later cropping, and am making sure that
the camera is within it’s focus range. I seem to only be able to
take macros in close up mode, and have not figured out how to
manually focus or adjust the f-stop in this mode. I have seen other
very sharp macros taken with this camera, so I know I must be doing
something wrong. I also have questions as to what I should be
setting my picture size at within the fine pic setting and how I
should be saving, for any possible future publication. I have been
saving as an uncompressed tiff and as a photoshop PSD file. Any
help offline or on would be greatly appreciated. Sorry if this is
long, but I thought I should describe my set-up a little for
clarity.

Jessica Daman


#2

Jessica - You need to set your camera to give the aperture setting
priority for the exposure. Then change the aperture setting to the
largest number. This will close the lens down as far as possible
and give you greater depth of field. Steve Brixner


#3

Jessica,

 The center of my piece seems to be in focus while the edges are
not. 

What this indicates to me is that the depth of field is too shallow.
Use the setting that lets you lock the aperture setting (f-stop) and
set it to 19 or so. I’m betting that if you look at your camera in
your current setup, you’ll see that it’s at f-3.5 to f-6.

The smaller the aperture, the greater the depth of field. It’s
possible to shoot images that look almost flat, because every detail
is sharp, so I don’t like to run the f-stop much higher than 19, and
for some shots I back it off even further.

The f-stop is a number that describes the opening behind the lens.
It’s actually the denominator of the opening, in inches, i.e., f-2 is
1/2 inch, f-5 is 1/5 inch, etc.

Loren
http://www.golden-knots.com/


#4

Loren; Your post to Jessica puts me in mind of to things. What you
stated about using smaller f-stops (larger numbered ones) is
correct. The smaller the aperture (larger the f-stop number) the
greater the depth of field. When I made my original post, I assumed
that Jessica had read the instruction manual and knew about the
relationship between f-stop and depth of field.

But having read some recent instructions that basically said buy
(and install) batteries, open lens cover, point at object to
photograph, push button - I could have been wrong. I am properly
mortified at my own ignorance, please forgive me Jessica.

Anyhow , Jessica, make sure that you have your camera adjusted to
obtain the greatest depth of field.

If, you have plenty of depth here are a couple of other hints.
Adjust the f-stop so that what you want in focus is covered and no
more. A good camera will have a depth-of -field preview button on
it. This does two things. One, it allows you to shoot at the fastest
speed, which minimizes things getting blurred because of camera
movement. Second thing: lens usually image their sharpest (have
their best resolution) a couple stops down from the smallest aperture
(largest number).

Loren.

I am sorry to inform you, but you are incorrect in stating that the
f-stop is the diameter of the lens aperture in inches with f2
equaling 1/2", f5 equaling 1/5", etc.

Logically, most, if not all lens (excluding view cameras and older
film cameras) are measured in millimeters. 50 mm, 100 mm, etc. Why
would they, in essence, measure their length in millimeters and their
width in inches?

Here is the correct

The f number is the reciprocal of the ratio of the lens length to
the aperture diameter. For instance: if the lens is a 100 millimeter
lens and the diameter of the aperture is 50 mm the diameter is 1/2
the length. This gives an f-stop of 2. With the same 100 mm lens,
if you adjust the aperture to 25 mm, it is 1/4th the lens length.
This works out to a f-stop of 4.

In case you are wondering why the numbers are so odd, (1.2, 1.4, 2,
4, 5.6, 8, 11, 16, etc.), here is why.

The lens aperture is set up to give you exposure changes of twice as
much or half as much with each full change between the listed
numbers. The odd series results because these numbers, to give that
result, have to vary with the square of the aperture.

Hope this helps. Any questions, please ask. I obtain so much
from all you people I love it when I can chime in on
something I know about.

Sincerely,
Eric


#5

Eric, Thank you for the clarification on the proper meaning of
f-stop. I suppose that I must have misunderstood it when it was
explained to me, way back when, and it never occurred to me to worry
about it. I looked through a lens that was set to f-2 and the hole
looked like it was about a half an inch in diameter, so I thought I
had it figured. It was probably a 60mm lens. Dang. :wink:

Loren
http://www.golden-knots.com/