[photo-3d] vivitar3700

[boris@xxxxxxxxxxxx]

Hello:

I am using a new (old) flash with my twin rig.  Had to say that to stay
within the charter of this group!

It's a vivitar "auto thyristor" 3700.  I've pretty much figured out how it
works, but a few details have me stumped.  Though these may be
inconsequential, I thought I would ask the flash congnoscenti on the list.

I uploaded a scan to illustrate my questions (this scan is a negative of
the black body of the flash):
http://starosta.com/vivitar3700.jpg

The top part of the flash does not control anything, instead serves as a
calculator for setting the lens aperture.  In the image, the calc. is set
to 50ASA (white dot ASA indicator), and shows three f-stop settings for the
three auto power modes (red, blue, orange): f1.4, f2.8, f5.6.  Plus this
shows the useful ranges of these power modes.  These are in fact correct,
as I have tested the flash with a meter.

Here's a question on this top part calculator: the button with which one
sets the ASA on the calculator is itself marked prominently with a vert.
white line.  What if anything does this indicate?  If you go by the button,
instead of the white dot, everything is off by one stop.

To the leftmost part of the slider is a little yellow triangle.  WHen the
slider is all the way to the right, this triangle points to 100ASA.  What
does this indicate?  I can't help but think of bounce flash, but the bounce
is automatically metered in the three auto power modes.

The lower part of the flash is the thyristor control.  One slider sets the
flash to one of three auto power settings, and manual.  But above this is a
slider that indicates ASA, plus a setting "FG."  This slider does not seem
to affect flash power at all.  I cannot figure the purpose of this slider.
ANyone?

reply privately or on tech-3d?

Boris


- Not content with ignorance of the past,
- humanity seeks the counsel of oracles.
-
-                                     J.P.V.D.Balsdon, _Romans & Aliens_

Boris Starosta, manager               boris@xxxxxxxxxxxx
Dynamic Symmetry, LLC                 http://www.starosta.com
usa - 804 979 3930                    http://www.starosta.com/3dshowcase