Handbook of High Speed Photography - IET Labs, Inc.

Type 1540 STROBOLUME*
ELECTRONIC STROBOSCOPE
brilliant white light
0 to 25,000 flashes per minute
wide-beam flood area for photographs
With the aid of a stroboscope you can examine the
motion of machines, objects in flight or exploding, fluid
spray patterns, and many other events as though they were
motionless. With a calibrated stroboscope, you can meas
ure the rate of repeating motion to a 1% accuracy up to
Vt million rpm.
With the new bright-light 1540 Strobolume, you can do
all of the above under more difficult lighting conditions
and even take color photographs of the strobe-stopped
events. The 1540 is the first stroboscope to generate so
much light, yet be fully versatile for general-purpose uses.
Three control units are available; with the right one for
the job, the 1540 can be flashed continuouslyor synchro
nized with the motion or camera for single flashes or
bursts. Thus, it will "hold" a repeating motion in one
chosen position, freeze a once-only event on film, or ex
pose a motion to multiple-flash analysis.
Every flash, a pulse of white light lasting less than
15 microseconds, illuminates a 7 by 13-foot area at a 10-
foot distance with enough light for still, movie, or, for elec
tronic recording, TVpictures.
The flash can be triggered from a photoelectric pickoff.
the opening or closing of a switch contact or camera
shutter, or an electrical pulse or sine-wave signal. The
flash can occur at the instant of Ihe triggering event or
be delayed by any desired time from 100 microseconds
to 1 second to catch a subsequent event.
All three control units accept external signals for trig
geringthe flash. In addition, the 1540-P4 Oscillator/Delay
contains a circuit that will either oscillate to produce con
tinuous flashing at rates from one-every-twe-seconds to
over25,000 per minute or willdelay external input trigger
signals from 100 microseconds to 1 second. The Oscilla
tor/Delay is well suited to photography; with it the flash
of the 1540 can be synchronized with the motion and a
camera, occurring only when the shutter is open and the
moving object is in the desired position. The 1540P1
Strobolume Oscillator provides accurate continuous Hash
ing of the Strobolume for 1% speed measurements from
110 to 25,000 rpm. The 1540-P3 Strobolume Control Unit,
simplest of Ihe three conlrol units, flashes the 1540 only
in response to external signals.
DESCRIPTION
The working part of the 1540 Strobolume is the lamp
head to which one of three control units attaches, either
directly or by extension cable for remote operation. The
combination is small, easily handled, and tripod mountable.
It is connected lo the larger power supply/carrying
case by a twelve-foot cable.
In use, the lamp is aimed at the object to be studied at
a distance determined by the area to be illuminated and
Ihe amount of light needed. The camera (any ordinary
type with "X" flash synchronization) and photoelectric
pickoff are connected to the control unit and the controls
set until Ihe motion appears stopped al the right point.
Set the Strobolume for single flash, operate the shutter,
and you have a picture. When not in use. all parls of the
Strobolume are stored and carried in a compact Flip-Tilt
case that protects the equipment from dust and damage.
1540 Slrobolume shorni with lamp head and all three
able control units.
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