In article <>,
Rita Ä Berkowitz <ritaberk2O04 @aol.com> wrote:
[ ... ]
>Anyway, I had a chance to try this setup outside today. I'm finding it
>really difficult to manage proper lighting, keeping the camera steady, and
>staying focused on a moving insect. I got a shot of an inchworm; well this
>guy was not much bigger than a half an inch and about 1mm in diameter. As
>you can see some of the lighting issues I had since I had the camera in one
>hand and the SB800 in the other.
It might help somewhat to set up a bracket to hold the SB-800 in
a fixed relationship to the camera and lens.
>http://www.geocities.com/ritaberk2003/eBay/Inch_b.jpg
>
>Do you know of a way I can keep the same magnification factor and increase
>the subject/lens distance to several inches? I have to come up with a
>better lighting technique that is easier to use. Thanks.
What I would suggest will take some searching, but will handle
the lighting and the closeup all at once -- since IIRC you are using a
Nikon D70.
Look for an old Medical Nikkor. It is a 200mm f/5.6 lens, with
a set of screw-in diopter lenses and a built-in ring flash. It is too
old to work as an automatic exposure setup -- but it is designed to
handle that part for you. You set the ASA (ISO) on one ring, and the
reproduction ratio desired (determined by the selection of diopter
lenses), and this sets your aperture correctly.
You are fairly far away at the maximum ratio, and a lot more
distant at the lesser ones.
The only problem is that at a minimum ISO of 200, it is too
bright for the highest reproduction ratios. The solutions are:
1) The special cord which connects the power supply to the flash
head which includes a resistance and reduces the brightness
of the flash. (I wish that I could find the information, so I
could make my own.)
2) Add a 2X ND filter between the lens and the stack of diopters.
Oh yes -- outdoors, you will need a *long* extension cord, or to
find the battery pack alternative to the AC powered supply, or to build
an inverter power supply to run from batteries which are more readily
available. With this, you could add a switchable resistor or switchable
capacitors so you can reduce the flash power without a special cord.
Aside from the built-in ring flash, there are also four small
incandescent bulbs turned on by a pushbutton on the housing for a
focusing light.
O.K. Here is a list of the reproduction ratios, with the
focusing distance from the front of the lens:
================================================== ====================
1/15 Master lens only 10' 11.99" 3350 mm
1/8 1/8x + master 5' 10.08" 1780 mm
1/6 1/6x + master 4' 4.64" 1337 mm
1/4 1/4x + master 2' 11.04" 890 mm
1/3 1/4x + 1/6x + master 2' 10." 635 mm
1/2 1/2x + master 1' 5.32" 440 mm
2/3 1/2x + 1/4x + master 1' 0.72" 232 mm
1x 1x + master 8.66" 220 mm
1.5x 1X + 1/2X + master 5.98" 152 mm
2x 2x + master 4.17" 106 mm
3x 2x + 1x + master 2.76" 70 mm
================================================== ====================
At 200 ASA (ISO) you are blocked from using 1:1 1.5:1 2:1 and
3:1 ratios, unless you can reduce the flash output.
The maximum distance will require an ASA (ISO) of 500 or
greater.
The standard battery power pack requires a 240V battery, and
four D cells to power the focusing lights.
There is another feature which will be useless with the D70.
That of imprinting the reproduction ratio (or a frame number) onto the
bottom-right corner of the image -- because this is in part of the area
not covered by the 1.5 crop factor of the D70's sensor. It can be
turned off, so there is no scattered light from it.
I have measured and verified that the flash sync voltage is
within the safe range listed for the D70 -- and the manual says that the
camera may be used with this lens -- with an AS-15 flash adaptor to
provide a PC connector.
If you want to see an example shot with this lens, the following
is one of a spider, which had taken up residence between the storm
window and the main window of our bathroom last summer, and who lasted
well into the fall.
This was taken through the bathroom window, and through some of
the webs woven by this spider. And it was handheld. It was at the
2/3:1 ratio -- the closest that I could get without a ND filter or the
modified power pack cord.
http://www2.d-and-d.com/misc/EXAMPLE/spider.jpg
Enjoy,
DoN.
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