Charles,
I made a bunch of calculations that support your math but you assume that
1/60th @ f8 is the correct exposure for EI 100 film. This exposure
corresponds to "Heavy overcast, no shadows" conditions. So we can fill
shadows using the T32 at full manual power at normal distances only when
there are NO SHADOWS!!
I haven't made test photos but my math indicates less desirable distances in
a Slight Overcast condition. In this light, the main exposure is 1/60th at
f/16 (EI 100). Using a unadorned T32 at full manual power the correct
distance is 6.5 feet (by my math) using a lens as wide as 28mm. I figure it
makes more sense to put a T32 Zoom Adapter on it, set at 50mm and shoot from
7.4 feet.
In full sun, using EI 100 film, you need a lens that stops down to f/22
because you're limited to that slooooow 1/60th sync speed, using maybe the
50/3.5 macro or a short tele. Forgetting for a minute that lenses aren't
critically sharp at f/22, the correct flash distance (filling in the shadows
which you'll certianly have in full sun) is 4.7 feet. [Full manual, GN104
in feet, distance = 104/22 = 4.7 feet]
Most interesting to me though, is this scenario, assuming you have both a
100mm lens and the Zoom Adapter. Using EI 100 film, Full Sun (distinct
shadows), 1/60th at f/22:
-Shooting Distance / Zoom Adapter setting in mm-
5.9 feet / Zoom Adapter @ 100mm
5.7 feet / Zoom Adapter @ 75mm
5.4 feet / Zoom Adapter @ 50mm
4.7 feet / no Zoom Adapter
I look forward to making test exposures to confirm these calculations and to
judge the results.
Jim L'Hommedieu
ps. Using a polarizer to reduce the f stop of the main exposure doesn't
really "buy" you anything cause it also reduces the flash exposure by a like
amount, making the working distance even shorter (worse). We need more
flash output so cutting to the 1/2 manual setting makes things worse too.
By my numbers, we need big, handle mount, wedding flash units to do fill
outdoors beyond 8 feet.
-----
"Charles Loeven" said,
>>>>>
The T-32 does not really have a auto fill function.
You will have to use the standard mathematical system for fill.
On full manual, iso 100, GN = 104.
Find a f stop to give you 1/60 or slower.
divide the f stop into the GN and that is how far away the flash should be.
You can reduce the f stop with a polarizer filter or a ND filter if need be.
Or, if the flash is on camera check the distance to subject and divide that
into the GN. That is your f stop. You can reduce the ratio by setting the
manual setting to 52 instead of 104.
Make your calculations and adjustments depending on film speed.
Example: iso 100 = GN 104.
At f 8 divide 8 into 104 and get 13. 13 feet is where the flash should be.
A zoom helps with composition here.
Or: At 13 feet GN of 104, divide 13 into 104 and get f 8.
I hope this helps and I hope I am right.
Charlie
>>>>>
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