Hi Mike,
I hope I can help you with my poor "german" english. The flash synchronisation
time is based on the construction of the shutter of the camera.
For cameras with a curtain or laminate shutter which moves horizontal or
vertical in the back of the body there is a limited shutter speed for flash
synchronisation, e.g 1/50 for Leica M, for Nikon F3: 1/80, for Nikon F4: 1/250,
for Nikon F5: 1/300 (if you want) and so on.
The synchro time depends on the speed of the shutter itself that means the
shortest time that the shutter is totaly open. With faster speeds there is only
a stripe or window to exposure the film which runs from the left to the right or
from top to down. If you use a flash with a faster time than synchro speed
youīll get a dark fraction of your picture where the flash doesnīt reach the
film. In that case you need theoretical a flash light duration for the entire
moving time but the regular flash duration is much faster. (I dontīt want
explain the short-time-synchronsiation of the F5 now!)
If you use a camera with compur or central shutter (in the lense) - I dontīt
know the exact english word- like Rolleiflex 6x6, Mamiya 67 or 7 etc. you donīt
have a window which runs vertical or horizontal. The compur shutter is like a
circle which closes from the border to the center. That means you dontīt have a
moving stripe, you have only a different size of the exposure circle dependig on
the aperture you use. The speed controls the opening time of that exposure
circle and the flash reaches always the whole open circle. Therefore you can use
all available speeds with no limitations of sychronisation for flash usage.
The time setting on the camera depends on the effects of flash you want to get,
eg. for the usage of available light. The flash settings are principle
controlling the flash duration time only, they have nothing to do with the
shutter speed of the camera.
I think itīs better to use the SB-26 with manual mode "M" on a dump camera to
control the exact distance resp the flash duration time.
Regards Ferdinand
> Date: Wed, 07 Apr 1999 13:06:14 -0400
> From: Mike Rohde <[EMAIL PROTECTED]>
> Subject: SB-26 used in "A" on a dumb camera [v04.n340/24]
> Message: 24
>
> I need to use my SB-26 on my MF Bronica. I will be using the strobe in
> "A" mode. So, I set the ISO of the film on the strobe. Select the
> aperture based on the subject to flash distance (being sure that the
> subject lies with in the indicated distance of the LCD on the strobe).
> The question is: What shutter speed is the LCD data based on. The manual
> says "Set the camera to its highest flash sync shutter speed". On a N70
> that would be 1/125th on a N90 it would be 1/250th. On my Bronica it can
> be as fast as 1/500th. Does this scale default to 1/60th (the most
> common flash sync speed). Please advise!
>
>
> Thanks,
> Mike
>
> ------------------------------
