Re: [photo-3d] vivitar3700 (improved)

["David W. Kesner" <drdave@xxxxxxxxxx>]

Boris Starosta writes:

> 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.

The white line on the slider is the ASA indicator. The white 
dot is most likely a compensation indicator. It seems to be 
just a hair under a full stop different.

Have you tried the flash in full manual mode to see what the 
actual GN is? Manufacturer's way over rate flashes. Perhaps 
the line is for full manual and the dot is for the three auto 
thyristor settings. (Just guessing here).

> To the leftmost part of the slider is a little yellow triangle.

I don't know about this thing. It may have to do with the 
dedicated modules.
 
> The lower part of the flash is the thyristor control.

Actually it is a dedicated module for a Nikon camera hence the 
designation DM/N2 (Dedicate Module Nikon 2). There are 
different modules for different makes of cameras as well as 
different models. I know there is also a DM/N for other Nikons.

> 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.

This is used to feed information to the camera. The FG is a 
model of Nikon and when set to this allows the camera to feed 
information to the flash. This module was made for the Nikon 
FG in full TTL mode, but probably also works for other Nikons 
in a dedicated mode.

The difference between TTL and dedicated is that in TTL the 
camera reads the flash through the lens and shuts it off when 
it has enough light. Dedicated flashes just exchange 
information such as being able to see the flash settings in 
the camera's viewfinder.

The main thing you need to be aware of is that some 
dedicated/TTL modules can short if used on the wrong camera. 
For example using a Nikon module on a Pentax camera. This can 
possible fry the module, the flash, or the camera.

Hope this helps.

That's all for now,

David W. Kesner
Boise, Idaho, USA
drdave@xxxxxxxxxx