| They should not be allowed to call them
"ready lights" lights. Instead, they should call
them "Freddie lights" or "reddish lights"
or they could call them "I’m ready, honey, lights"—then
we’d know that they really mean "I’m getting
ready," "I’ll be ready soon," "I’ll
be ready someday," or "by the time I’m ready,
the party’ll be over." The manufacturer decides
at what point during the charge cycle the ready light is to
come on, and this decision may be affected by marketing considerations.
Most strobe capacitors measure around 350 volts at full charge.
The ready light may be designed to come on at any arbitrarily
set voltage. When strobe comparisons are made, the buyer commonly
watches to see when the ready light comes on, and fires the
strobe, then waits for another ready light. The time between
ready lights is assumed to be the recycle time. In order to
have their strobe compare favorably, manufacturers may lower
the ready light turn-on voltage—sort of a ready light
come-on—come on. We compared over a dozen strobe models
by metering their outputs at three points. We fired and metered
them at the point the ready light came on, at ready plus five
seconds, and at ready plus thirty seconds. We found that the
best performer, relating ready light to peak power, put out
one-quarter stop more at ready plus five seconds than at ready
light, reaching full power within the five second period.
For all practical purposes, this is probably not going to
get much better. The phoniest baloneyest ready light came
on almost two stops short of full power and took the full
thirty seconds to drag itself to the top if its peak.
If you’re looking for consistent recycle times, and
you want them as short as possible for the strobe you don’t
have, don’t use alkaline batteries. They’re slower
than NiCads when fresh, and the alkaline batteries will give
slower recycles and less peak power as their voltage drops
with use. NiCads are faster and will be much more consistent
in both recycle time and peak power as they’re discharged.
Place a freshly charged set of NiCads in your strobe and
shoot a test roll. Since you shoot TTL, set everything up
for TTL and determine the aperture and strobe-to-subject distance
at which the strobe is just putting out full power by finding
the "blink point." Find this point by starting with
the in-air guide number and making successive exposures thirty
seconds apart with one-half f-stop adjustments on the lens
until the ready light starts blinking after the flash goes
off. Open up to the last f-stop that didn’t blink. After
at least a thirty second delay, take a test exposure. This
is your control sample. Make a second exposure as soon as
the light comes on. The next time the light comes on, start
the "Lawrence Welk" count immediately (ah-one ana-two
ana three-ah), and push the shutter release on three. Repeat
on a count of five, then ten, then fifteen, then twenty, then
thirty. Develop the roll and check for the first exposure
that looks like the control. The count you made on this exposure
is the full-power recycle time. There is additional useful
information on the roll. You may find that you can short the
full-power recycle time by half and only lose a quarter of
a stop. You can now decide how much you can cheat when you
need a quickie.
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