On Sun, 9 Jun 2002, Richard Martin wrote:
> In my understanding there are two basic ways to deal with a
> fill-flash situation. One, set your camera exposure for the
> ambient light, taking care to choose a shutter speed that will
> sync with the flash, then adjust the output of the flash to get
> the fill you want. Two, again set the camera exposure for the
> ambient light, then adjust the flash-to-subject distance.
Hi, Richard ---
[The method I outlined is simply a refined, easy-to-use
version of the latter, that is all]
> I
> don't see that the shutter speed has any relationship to what
> the flash is doing or has anything to do with ratios.
You are overlooking the fact that, although it has nothing to do
directly with the flash exposure, it can alter the ambient exposure
outright, and/or *allow* a different aperture (by changing shutter
speeds, and thus retaining the ambient exp, while changing aperture &
the effective flash exp). Either of these changes the
lighting ratio, assuming flash output is unchanged.
The little table I put up there is directly out of a Kodak Photoguide,
BTW. It's been in use for decades.
Although it may seem counterintuitive to you, the method outlined
is a calculation-free fast (once you have the table taped onto your
283) way of getting perfect fill ratios.
> A slow sync speed CAN present a problem when there is
> movement in your subject. Then you can get "ghosting", where the
> flash part of the photo is sharp but the ambient light part is
> blurred. Perhaps this is what you are referring to.
No, that is not -in the slightest- what I am referring to. What I
was referring to was the answer to your original question in a proven,
time-tested way. A way that is eminently useful with any flash unit
for which you have ascertained the true BCPS output.
--- Luis
