Hi Leon,
The beam splitter is not to divide the flash beam,
but to allow the flash to enter the normal light
path from the microscope's Halogen or HBO50 light
source. I often turn down the internal light, or
shut it off, before using the flash. But this is
not necessary at high magnification when the light
is not very bright and the flash is the main
contributor to the exposure. The beam splitter is
a piece of glass. I have considered a 50% surface
coated (interference) filter, but they are damned
expensive. The flashes usually have enough punch
to make plain glass usable. If TTL works with the
extension cord I won't have a thing to worry about.
Don W
Leon Altoff wrote:
Hi Don,
If you are going to use a beam splitter to send light out the objective
to light the subject then I would consider getting hold of an AF360FGZ
and modifying it to work. The tube in the 360 is slightly shorter from
memory - it's been a while since I had mine apart that far. I spliced a
second head at the end of about a foot of cable onto one of my 360's to
make a lightweight twin headed macro flash. The second head can be
unplugged and the flash then works as a normal flash.
I would consider using the wireless trigger on the flash as it's one
less cable floating around. Otherwise you will need to use a 5P cable.
Leon
http://www.bluering.org.au
http://www.bluering.org.au/leon
Don Williams wrote:
Hi Leon,
The flash, which is made from a Polaroid unit and a single straight
flash tube about 50mm long, works very well as a flash. But the tube,
which lies across the beam, causes diffraction in the images. In other
words it doesn't work very well in the microscope. I intend to use a
beam splitter and direct light from a standard flash into the path. I
may even be able to use TTL if I can find a connector that will
satisfy the camera. So the problem now becomes -- "How can I trigger
the Vivitar on the table about 24" away from the camera and what
extension lead do I need?" The camera is on the top of a monocular
mount behind the binocular and using one flash to trigger another
would be very dangerous and unstable. I can imagine the camera up on
top of this 'Xmas Tree' with a flash in the shoe. Something would give
very soon. It would get in the way of my head in any case.
Don
Leon Altoff wrote:
Don,
The flash on the microscope may have too high a voltage for the ist
D. Once it flashes it may be locking up the camera. Try measuring
the voltage or disconnecting the flash flash after each exposure.
You may not want to keep doing this too often in case it permanently
damages the camera.
A solution to this could be using a slave unit on the microscope and
triggering it with the Vivitar flash.
Leon
http://www.bluering.org.au
http://www.bluering.org.au/leon
Don Williams wrote:
Hi all,
I'm still waiting for the replacement camera and am using the one
with the faulty internal flash. It works with an external flash
Vivitar 730 AFPK perfectly ... but.
On the microscope, which has a simple flash device with no
synchronization, or TTL, or anything at all automatic ... the flash
will flash once and then not again. Its not a question of charge the
flash is made to strobe and will go on flashing with a film camera
until the cows come home at 1/2 second intervals.
What am I doing wrong? I haven't spent much time learning -- I've
been using the camera and it works fine with ordinary lighting on
the scopes. In green, M, or any other setting I might like to use.
All I want is for the flash to flash each time the shutter is
opened. The exposure is controlled by other means and the camera is
not expected to think about this.
Don
--
Dr E D F Williams
__________________________________
http://www.kolumbus.fi/mimosa/index.htm
http://personal.inet.fi/cool/don.williams
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