Alan quoted Chuck thus:
> The T-32's guide number is for 24mm coverage.
Then went on to say:
Interesting, as the quoted specs for the T-32 do not seem to follow.
They show having to use the zoom adapter with the T-32 set at 50mm
coverage to achieve a 36m/118ft guide number. The Sunpak 433 is GN
120(ft) 35mm coverage with no adapter required, and it goes up if the
fresnel zoom is used.
I have not tested them side by side like you have, and the T-32 does
sound like it's wide coverage is quite good. But the published specs
show the sunpak to have the edge. (Maybe the 383 is weaker than the
433/444?)
The T-32 clearly is a more elegant package! I also suspect it's a bit
sturdier. The Vivitars and Sunpaks are clunky and less balanced in
comparison.
------------------------------------
I don't know anything about T-32 zoom adapters. I've never seen one or
the instruction sheet for same. As to coverage angle I was quoting the
eSIF and the T-32 instruction sheet which gives the coverage angle as 53
degrees vertical and 74 degrees horizontal. That yields 90 degrees on
the diagonal which is actually a bit more than the 84 degrees specified
for the Zuiko 24's. I don't know what the specification might be for
light falloff at the edge of the field. I can only tell you that I have
tested it at the edge of the field for a 28mm lens and find the falloff
to be 1/2 stop. Given the falloff, I'm sure the T-32 spec is optimistic
and assume the others are as well.
If I left the impression that I have tested Vivitar and Sunpak flashes
against the T-32 let me correct that. I have not. I have a Vivitar
283, a Sunpak 522 and a Sunpak 422 (which is unfortunately dead at the
moment). I have never tested the light output from either of them. The
only evaluative tests I have performed have been to measure the Alien
Bees B800, the T-32 and an unknow Lumedyne head driven by a Lumedyne
50/100/200 watt second power pack as I related in my earlier post.
Perhaps I'll test the others now that a question has arisen as to the
veracity of the coverage angles and guide numbers.
One final point. Since the start of this thread was the use of T-32's
as studio flash I will point out that the compact size of a T-32 makes
mounting it on a light stand with umbrella easier than a large bodied,
tilt flash such as the Vivitars and Sunpaks. When mounted standing on
their feet, these larger bodied flashes will not have the head near the
center of the umbrella. Two of them will also make a rather awkward
structure. Two T-32's mount nicely together and stay near the axis of
the umbrella.
Ooops. One extra small point in favor of T-32's. If used with an
external power pack such as the Quantum or SP-Systems pack I mentioned
before, the power pack will power the control electronics as well as the
flash tube. This means you don't need AA batteries installed in the
flash. Other flashes may require separate batteries.
Chuck Norcutt
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