Honeywell modeling slave 51-A / 52-A User manual

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Description

IIONEYVyELL MODELING
SLAVE STROBONAR CI{ARACTERISTICS

       Light Output         51-A Measured 480 BCPS
                                          at 40 watt seconds
                                      stored energy
                               52-A Measured 960 BCPS
                                        at 80 watt seconds
                                      stored energy
       Reflector Coverage  UO;iTrOle for standard
       Efiective Exposure  51-A 1/500 second
     Time               52-A L/250 second
       Color Temperature Approximately noon day-
          of Light                    light, ideal for daylight
                                      color films
    AC Power Source     110-130 volts, 50-60 cycles
                                  per second
     Height                   4r/2 inches
                                                s/a inches    Width                     6
    Length              8 inches
      Length Including
                                                   r/6 inches     Handle               9
       Total Weight         51-A 38 ounces
                             52-A 49 ounces

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                                                       Description

 I{ONEn,T/ELL MODELING SLAVE STROBONARS
  Models 51-A and 52-A
  Honeywell Modeling Slave Strobonars are going to give you better pic-
  tures! With their modeling lights you can actually see where shadows
  will fall and where the highlights will be. Proper exposure and light-
  ing contrast are easy; you can see your subject as it will be in the
  finished picture   and still obtain that crisp-quality sharpness of  Strobonar lighting.-
      Moderately priced, the Modeling Slave Strobonar opens to almost
  anyone the type of lighting that until now could be afforded only by
. the best of professional studios.
      Designed primarily for multiple lighting, one Modeling Slave
  Strobonar is connected to the camera and the others will flash in
  perfect synchronization without any connecting cords (the AC cord
  must be plugged in, of course).
     The Modeling Slave is ideal for color pictures. Its efficient light
  source provides illumination which closely matches daylight color film
  without need for separate filters. This smooth, evenly distributed light
  covers the full picture area for all nclrmal lenses.
     The Modeling Slave is operated by ordinary household alternat-
  ing current. Operation is simple. Plugging in the power cord of the
  Model 51-A turns on both the power and the modeling lamp. The 52-A,
  however, has a power switch and modeling light switch.
    Aim the collapsible periscope toward the master Strobonar. The
  convenient carrying handle doubles as an adjustable mounting bracket
  for easy positioning of the light.
     The Modeling Slave Strobonar is made of the finest components
    developed specially for photographic use. With the normal care  -usually given all good photo equipment, the Modeling Slave will give
 you many years of service.
 Two models of the Modeling Slave Strobonar are available to meet
  the needs of every photographer   the standard Model 51-A and the
 Model 52-A which gives twice as-much light. For added convenience
  in operation, the Model 52-A also has two ON-OFF switches on the
  rear case for the power and modeling lamp. The operation of the two
 models is the same except as noted in the instructions which follow.

Ll       Operation{il
i{
Hil   HOW TO PUT TIrE MODELING SLAVE!
    STROBONAR INTO OPEIIATION
        operation of the Modeling Slave Strobonar is simple and easy. A few
       minutes spent with this booklet and your new Slave will assure you of
        confidence and better pictures. An outline of the operating procedure
          is provided as a convenient check list. Use the outline only after you
       read and understand the operating instructions which follow.
     CAMIERA.FLASI:I SYNCITRONTZATION
      The Modeling Slave is designed for taking pictures with cameras hav-
       ing built-in flash contacts. If your camera has a between-the-lens
        shutter with X-contacts (zero delay), the Modeling Slave will syn-
        chronize with it at all shutter speeds up to the limits stated on page
       10. If your camera has a focal-plane shutter with X-synchronization,
            it will synchronize only at slower speeds   up to L/25 or 1/60 second.                                               -        (See your camera instruction manual.) Most                                               cameras without built-in
       X-synchronization (zero delay) can be easily adapted for the Model-
       ing Slave by a competent repairman. If you wish to check the syn-
        chronization yourself, see instructions on page 28.
    MOUNTING TIIE MODELING SLAVE
    STROBONAR
     The Modeling Slave's carrying handle also serves as an adjustable
      mounting bracket complete with mounting threads to accommodate
        all standard tripods or light stand adapters. Just thread your tripod
      or light stand adapter (an optional accessory, catalog No. 964)
      mounting screw into the bracket, and then adjust the Modeling Slave
       position to light your subject as you choose. The friction-type bracket
       holds any position selected without the use of additional locking screws
      or clamps. Just push the slave up or down through any angle. The
      modeling light shows you the exact area the light will cover.
      4

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                                                    Ope rat io n

OPERATION OUTLINE

  1. Plug AC cord into wall outlet (this turns on power and mod-
      eling lamp in 51-A )
 2. Turn on power (Model 52-A only)
 3. Form capacitor (see page 7)
 4. Mount Slave on tripod or light stand
 5. Turn on modeling lamp (Model 52-A only) and position Slave
 6. Pull out phototube periscope and aim toward master light for
     Slave operation, or, connect shutter cord to Slave unit and
    camera for use as master light
 7. Determine exposure
 8. Set lens aperture and shutter speed
 9. Shoot picture
10. Wait 10 seconds before shooting next picture

OPERATION IN GENERAL
The Modeling Slave is operated by household current and is ideally
suited for all your indoor photography. The Slave is designed to oper-
ate from a 117-volt source of 60-cycle alternating current, standard in
most U.S. localities, or from 117-volt, 5O-cycle current available in

Operation

 many European countries. Just plug the line cord into the wall outlet,
 and the unit is ready to go. The Model b2-A has two switches on the
 rear of the case   one for power and one for the modeling lamp. Each                - switch has a red                dot to indicate the "ON" position. Although the mod-
 eling lamp has a long life of several hundred hours of continuous oper-
 ation, you may prolong its useful life by turning it off during extended
 delays between pictures and at the end of the shooting session. The
 Modeling Slave Strobonar is fast in operation, being able to flash for a
 short sequence of pictures at 7 to lO-second intervals. Operation is
 efficient and economical, the only upkeep being the occasional replace-
 ment of the modeling lamp.

OPERATION AS A SLAVE UNIT
Any number of Modeling Slave Strobonars can be fired remotely from
a single master Modeling Slave Strobonar or other electronic flash
 unit. The extremely sensitive phototube triggers the unit in perfect
synchronization with the master unit, or the unit at the camera. The
Modeling Slave does not require extension or connecting cords, mak-
ing it an ideal flash unit for multiple-light arrangements. The Model-
ing slaves may be used at distances which depend upon the light
output of the master unit. using a Futuramic rr Model 6b-A, for
example, the Modeling Slave may be used as much as 85 feet away.
The directional periscope, when aimed with its arrow pointing toward
the master unit, narrows the angle of sensitivity to prevent the Slave
from being triggered by other flash units operating in the area. A
special feature of the Modeling Slave, the collapsible periscope, pulls
out easily for slave operation, and tucks away flush with the case
when not in use. The sensitive phototube remains safely and securely
mounted inside the case. used as a main light, a fill-in light, or a
bounce light, the Modeling Slave Strobonar is a versatile tool for the
most exacting photographer.

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                                                      Operation

OPERATION AS MASTER UNIT
Because the Modeling Slave Strobonar is so convenient to use with
its built-in modeling light, you'll want to use one for the master unit
as well as for the extension Slaves. As a master unit, the Slave is
triggered by the camera's flash contacts. Just connect the shutter
cord from the camera's X-contacts to the two-way receptacle of the
Slave. An exclusive Honeywell feature, this receptacle permits the
cord to be placed on either side of the unit, whichever is more con-
venient for you. The phototube periscope on the master unit can be
either extended or collapsed.
FOR,MINGI (IMPORTANT)
When the Modeling Slave has been out of use for even a few days,
plug the unit into a wall outlet (and turn on the power for the Model
52-A) to form the capacitor. After about five minutes, flash the Slave
nine or ten times before making pictures. This can be done either
with the camera flash contacts or the Honeywell manual tripping cord
53-1, a very useful item of optional equipment. If a week or more has
elapsed since the Slave was last used, form for 15 minutes. Flashing
the unit several times will bring it up to peak efficiency and give you
a consistent light output. Several Modeling Slaves can be flashed at
one time by raising the periscopes and triggering with the master unit
as described on page 6. The Modeling Slave Strobonars thrive on fre-
quent use   use them often!          -
MODELING LAMP-rts  use
Photographers skilled in the use of controlled lighting emphasize the
importance of being able to see the effect of the lighting setup before
the picture is made. The Modeling Slave Strobonar is so successfully
engineered that the modeling light coverage is virtually identical with
the coverage of the electronic flash. When your Modeling Slaves are all
of one Model    either the 51-A or the 52-A   you will want to use the             -                            -

'g

 Operation

 standard 2l-watt modeling lamp. rf, however, you are using both the
 Model 51-A and the 52-A, you may want to substitute the special
 l5-watt lamp in the Model 51-A. The smaller lamp has only half the
 light output of the 2l-watt lamp and will keep the intensity of the
 modeling lights in the same ratio as the intensity of the flash. This
 setup will give you an accurate preview of the lighting before you
 shoot the picture.
    The modeling lamp will give you several hundred hours of serv-
 ice. Like any incandescent lamp, it will lose some of its intensity as
 it begins to blacken with age. Aging of the modeling lamp in no way
 affects the output of the electronic flash, which remains constant. If
you are using an exposure meter to determine exposure from the mod-
 eling light setup, you will eventually need to compensate by stopping
down r/z to 1 f/stop from the indicated exposure. This method of
determining exposure is described on page 12.

MODELING LAMP- Replacenent
Replacing the modeling lamp is simple. Just be sure to discharge the
unit and wait for the lens and modeling lamp to cool.
              vyAn,NTNG
    Before attempting to replace the modeling lamp, discharge
     the stored energy by fi.rst disconnecting the AC line cord and
     then flashing the slave unit. Hold the lamp to be removed or
     inserted by the glass bulb and do not touch the inner lamp
     socket with fingers.
When the lens is cool enough to handle, remove it by turning a quarter
turn. Push the modeling lamp straight in and turn it counterclockwise
to release  it.
     Insert the new modeling lamp in the bayonet socket; push straight
in; and turn it clockwise about r/a turn. Align the two small lips of the
Slave lens with the notches in each side of the lens opening. Turn the
lens la turn.

Exposure

DETERMINING TEIE E>rPOslURE
Determining the exposure for even the most complex lighting setup is
not as difficult a problem as it might appear to the beginner in multiple
lighting. The suggestions presented in this booklet will assist you in
experimenting with lighting arrangements and in finding the proper
exposure. With a little experience, you will acquire your own ideas on
lighting, and your own method for determining the exposure. The two
methods of determining exposure described below involve the use of
guide numbers, or the use of exposure meters to determine exposures
from the modeling lights. You will readily see how convenient both
methods become when all of the units in your multiple lighting system
are Modeling Slave Strobonars.

GUIDE NUMBER METI{OD
The proper exposure for pictures taken with electronic flash is easily
determined because of the fixed amount of light packaged in each
flash. No light is lost or wasted as the shutter opens and closes. The
amount of light reflected from the subject depends only on the dis-
tance from the flash to the subject and does not vary with the shutter
speed. With the 51-A and between-the-lens shutters, all speeds through
1/500 sec. may be used; with the 52-A, speeds through I/250 see. See
page 4 for focal plane shutter limits. With a fixed amount of light, it
is possible to determine the proper aperture (f/stop) if the distance
from the lamp to subject is known. Likewise, with a fixed amount of
light, it is possible to determine the proper lamp-to-subject distance if
the aperture is known. Thus it is possible to calculate a guide number
which will give an indication of the proper exposure. For any given
film, the guide number is the product of the f/stop and the lamp-to-
subject distance. Either factor can then be determined by dividing
the other factor into the guide number. Most guide numbers are in-
tended to give the proper exposure in a medium size room of average
light colored walls and ceiling. When shooting pictures in a very large
room or hall, the lens should be opened up one-half to one f/stop more
than is indicated by the guide number.

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                                                     Expos u re

    fn almost every lighting arrangement, there is one main light or
key light. Any number of additional lights may be used to achieve the
desired lighting effect. The general rule is to determine the exposure
for the key light only and completely disregard the other lights. There-
fore, for a single-light setup or for the key light of a multiple-light
setup, the lens setting is determined by dividing the Guide Number
by the distance in feet from the light to the subject.
Exarnple: Using the Model 51-A as a single light or as the key light,
you find the guide number for the film you are using is 110 (listed in
the table of Guide Numbers). The lamp-to-subject distance is 10 feet.
The distance divided into the guide number of 110 is 11, or f/ 11-, the
proper lens opening to set on your camera.

      SUGGESTEID GUIDE NUMBERS
                 (Black  and White  Ftlms)
                         Guide Numbers                             Guide Numbers
                   5r-A    52-A                       st-A     52-A
Fine Grqin lhin Emulsion Films               High Speed Films
                                            AnscoSuperHypon...........-190  270  Adox KB-14              .... 55       80                                                       llford HP-3       .--.17O 2&  Adox KB-17              -..- 75      ll0       Kodok Tri-X ......-...............170 240
  Agfo lsopon FF-.....-........... 50      70        Perutz Peromnio 25---....-....190 270
  Agfo lsopon F.................... 75      ll0      Polqroid Films
   llford Pon F....-................-.. 60       85                                        Type 32 & 41----------.....-......120 l7O
  Kodok Pqnotomic-X.......--... 60      85       Type 42,52, & 53-........... 85     120
  Peruiz Pergrono  .-.....-.....--- 55       80       Type 38 & 48........... -......-- 15      60
                                             Color Films (Daylight Type)
                                          Agfochrome CTlS  ....---..-.. 60       85
Medium Speed Fine Groin Filmr                Anscochrome D/50 .-.-..---. 60       85
                                           Anscochrome D/100 -....... 85      r20  Adox KB-21           ....120     170       Anscochrome D/2OO --..---.115      165
  Agfo lsopon  tSS..............-.120      170        Ektochrome X ..-.....--....-..-.- 65      95
  Ansco All Weother Pqn.--.-. 95      r30         Professionol Ektochrome.... 60       85
        f lford FP-3                  ---- 95      r30       High Speed Ektochrome...-ll0       150                                           Kodochrome X .....-..------.--. 65       95  Kodok Plus-X Pon....-...-.-...1 l0      150                                           Kodochrome  ll   ------.----.....-. 42       60
  Kodok Verichrome  Pon-.....1 l0      r50         Kodocolor X (Use 85 filter)55       80
  Perutz Peromnio 2l ----.--.----l2O      170         Perutz Peruchrome .--..---..-. 50       70

                                                                  11

Expos u re

EXPOSUBE METEN METI{OD
A convenient way to figure exposure for the Modeling slaves is to
determine the ratio of the incandescent modeling lamp to the electronic
flash, resulting in a factor to set in your exposure meter. Here's how
it works:
                                                                (If you're using    1. Set up your lights, using one or more slaves.
       bothS|-A,sand52-A's,use15-wattmodelinglampsinthe
         51-A's).
    2. Using the guide number for the key light, determine the proper
         f/stop for the film you're using. Let's assume this is f/8'
    3. Take the Picture.
    4. without disturbing the lights, take a reading of the subject,
       withyourexposuremeter,bythelightoftheincandescent
       modelinglamps.Besureyourmeterissetfortheproperrat-
       ingofthefilmyouareusing.Notetheshutterspeedopposite
         L/8. Let's assume this is l'l10 second'*
               @ t/lo second'     5. Record the data: f/8
    6. without disturbing the lights, bracket your original exposure
               one at f/5.6, and another at f./l].. Record the shutter
       -rnake        speedsindicatedbyyourmeterforthesef/stops.(Yourmeter
        willshow|/25sec.forf/5.6and1/5sec.forf/|L).
     7. Develop the film, and choose the best negative. Let's assume
             it's the exposure made at f'/ 5'6'
     g. Go back and check the shutter speed your exposure meter
        showedf'orf/5.6.You'llfindittobe|/25sec.
     9. This is your meter factor for future pictures. In other words,
        allyou'llhavetodothenexttimeissetupyourlights,make
  *The shulter speeds shown in lhis exqmple ore for meler foclorr only, ond ore nol lhe speeds
    ot which you will toke your pictures'

  T2

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                                                     Exposure

       an exposure meter reading of the subject lighted by the incan-
        descent modeling lights, and use the f/stop opposite l/25 sec.
         for proper exposure.
I{ONEYVyELL pEtrrAx a|Pt ExposuRE MEITER
The Honeywell Pentax 3/2L Exposure Meter is ideal for accurate ex-
posure determinations in multiple lighting arrangements. No other
meter gives you the extreme selectivity of the 3/21 Meter. Because
 the light-sensitive element coversi an angle of only 3o (within a 21o field
of view), you read the light intensity of the precise area you photo-
graph    peripheral light does not affect your reading. You can take      -the reading directly from the camera, regardless of the camera-to-
subject distance. At close range, the 3/21Meter allows you to meas-
ure the light reflected from several different areas of your subject to
determine the exact lighting effect you desire. This feature is especially
important when you want to maintain a certain ratio between the
brightest and darkest areas of your subject. with the B/2L Meter, the
lighting ratio you desire can be checked with utmost accuracv.





The Honeywell Penlox
3o /21" Exposure Meler

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                                                                  13

Multiple Lighting

MULTIPLE LIGI{TING
Why rnore than one?
 Why use more than one light when a single unit will give enough light
 for a picture? This is a timely question as it expresses a common mis-
 conception about lighting in general. The fact is that good lighting
 involves more than just the amount of light. The bright sunlight is
 often considered the ideal source of light and certainly  it is adequate
 in quantity; but did you ever see a really good portrait made in direct
 sunlight without the use of supplementary flash or reflected light?
 More often than not, the facial shadows are too harsh with the eyes
 (squinting, of course) lost in the shadows from the eyebrows. Visual-
 izing such a 1rcrtrait, you can imagine how it would be improved if
you could direct the light toward the subject as you desire; and if you
 could also control the amount of contrast between the lightest and
 darkest areas of the subject. The use of various multiple lighting
arrangements gives you complete control of these factors, and permits                                                                                                Iyou the maximum freedom of expression in photography.
     Controlling the quantity of light is important because it permits
you to select the other factors of exposure    film speed, camera aper-
 ture, and shutter speed. You are not restricted-    to the use of fast films
which will accommodate low levels of light, and which invariably re-
quire some sacrifice in grain quality and sharpness of detail in black-
and-white pictures, or the loss of rich color saturation in your color
transparencies. Shutter speed is not normally a factor in electronic
flash photography (except with focal plane shutters), but selecting anaperture to give you the desired depth of field can be very important.       I
rt is evident then that controlling the quantity of the light does defi-nitely give you advantages.                                                       I
    As you experiment with multiple lighting, the advantages of con-
trolling the direction and contrast of the lighting will become more
obvious. Additional lights add roundness and dimension to the subject;
separate the subject from the background; add interesting highlights;
permit the overall subtle effect of bounce lighting, and other effects

L4

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                                                     Multiple Lighting

     you will discover. Some ideas and suggestions for multiple-flash work
     have been included to assist .you on your road to better pictures
     through the use of controlled lighting.
   ARRANGING TIIIU LTGIITS
     The ease and convenience of working with Modeling Slave Strobonars
       is evident when arranging a kit of two, three, or four. The modeling
I      lights show you the lighting effect, and the exposure is easily deter-
     mined by either the guide number method or the exposure meter
I    method described on pages 10 through 13.
               rf, however, some of your lighting units have different guide num-
      bers, or have the same guide numbers but no modeling lights, the
     methods for arranging the lights and determining the exposure is a
        Iittle different. You already know that the amount of light varies in-
      versely with the square of the distance measured. This means, for
     example, that when the distance from the lamp to the subject is in-
      creased to two times the original distance, the intensity of the light
       is reduced to one-fourth. A few of these lamp-to-subject distances and
      intensity relationships are as follows:
                              Distonce         Intensity
                          x %        x4
               %2               t%%
               t%%
              2%
              z%%
        The above relationships ape the same as for f/stops, and you may
      find this an easier method of remembering. As an example, at 8 feet
     the intensity of a lamp is twice the intensity measured at 11 feet and
     one-half the intensity measured at 5.6 feet. To use this method, just
     think of the distance in feet as f/stops, and move the lamps by the
    number of feet to the next f/stop to halve or double the light.
        sometimes in a lighting setup it is not desirable to move a Iamp
      farther from the subject in order to reduce the light intensity. When

                                                                       15

Multiple Lighting

this occurs, a single thickness of a white handkerchief placed over the
lens of the lighting unit will reduce the light approximately one-half,
or by one f/stop. Two thicknesses will reduce the light to one-fourth,
or by two f/stops.
    As with the other aspects of multiple lighting, becoming familiar
with your lighting units greatly simplifies the mechanics of setups and
exposures. Having mastered these mechanics' you gain confidence in
the use of controlled lighting as a valuable photographic tool. Since
the use of any photographic tool is as individual as the photographer
himself, detailed instructions for the use of multiple lighting and the
innumerable arrangements possible would require several volumes.
Such an extended study would require time that could better be used
reviewing the examples of controlled lighting which follow and putting
                                                                         sgeyour own ideas into operation. Through the examples you can
what can be done with a single slave unit and with several units.
Regardless of the ecluipment you work with, it's the results that count!
LIGIITS OT' DIFFEIRENT IN:TINSITY
Even if you have several electronic flash units each wit}:, a difrerent
guide number, exposure determination does not have to be difficult
 for you. The procedure is to find a distance for each unit at which all
 the light intensities will be equal. Then move each lighting unit by
 distances in feet equal to differences in f/stops for that unit.
 Example: For a given film, your three lighting units have guide num-
 bers of 80, 80, and 110. Dropping the zeros from these numbers, you
 find that at 8, 8, and 11 feet respectively these lights all have the same
 intensity. To use the 110 Guide Number unit as the key light with
 a four-to-one ratio, move this light nearer the subject by an equivalent
                                                                                           f'ee;t- Any other distance of two f/stops, that is from 11 to 5.6 or 512
 divisor (we used 10 in the example) could have been used for deter-
 mining the one-to-one ratio distances if another set of distances would
 have been easier to use asi a starting point.

 16

Multiple Lighting





       o
18          No. I light (52-A Strobonor) only, triggered&by comero.

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                                          General lnformation



           ,q
               I                        I





                                                                         .*"'q*w.L*



            This is the three light set up os used in the preceding exomples.

GENERAL
PIIOTOGRAPI{IC INF'ORMATION
Taking better pictures with the AC Slave Strobonar
First of all, be sure your lighting units and camera are ready to go.
Be sure the AC cords are plugged in; the power and modeling lights are
                                                                2t

General lnformation

turned on (Modelfz-Aonly); the Slave periscopes are directed toward
the master light unit; the proper shutter speed is set; and the shutter
cord is connected from the master unit to the camera. If your shutter
has adjustable synchronization, make certain it is set at "X" (zero
delay). Then, before taking a picture, consider the elements of any
good picture    composition, lighting, balance of mass and color, depth            -                       dcale, qttd center of interest. Plan your pictureof field, background,
carefully. Consider the lighting effect you desire, and remember that
your picture is made when you press the shutter release.


BOUNCE LIGHTING
To obtain the softer, more subdued lighting sometimes desirable in
portraits, bounce the light from the AC Slave off the wall or ceiling.
The wall or ceiling should be a light, neutral color. Light bounced
from a colored surface will impart an overall color tint to your color
pictures. To determine the exposure for bounce lighting, estimate the
distance from the flash to the ceiling to the subject. Find the f/stop for
this distance using the guide number for your film. Then, open up at
least one full f/stop to compensate for the light absorbed by the ceiling.
   The light is usually aimed at the ceiling in such a way that the
bounce light falls directly on the subject. If the light is aimed at such
an angle that the subject does not receive the main portion of the light,
then allow one more f/stop in exposure.
   When using an exposure meter to determine the proper exposure
for the bounce light of an AC Slave, special consideration is not re-
quired. You simply measure the light falling on the subject from the
modeling light.

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                                         6eneral lnformation

 CIIEIC ISING SYNC IrRONIZATION
 If you are not sure about the shutter speeds at which your camera is
 synchronized for electronic flash, you can make this test yourself.
 Connect your camera to the Modeling Slave with the shutter cord.
 Set the camera at the widest lens opening and point the Modeling
 Slave at a light-colored wall so the reflected flash will be visible
 through the lens. Open the camera back and watch for light coming
 through the lens when you trip the shutter at various speeds. For
 compur-type shutters, synchronization is good when you can see a
 full circle of light, and you are getting the benefit of all the light fronr
 the Modeling Slave. You may use any of the shutter speeds that give
a full circle of light.
    In cameras having focal-plane shutters, the shutter speeds are
usually determined by a moving slit in the shutter curtain, or by
two moving curtains. It is only at slower speeds that these shutters
are ever fully opened, and these speeds are the ones with which elec-
 tronic flash can be used. To check the synchronization, watch first
from one side and then the other to see if each edge of the circle of
 light is visible. You may use any of the shutter speeds at which the
edge of the circle of light is visible from both sides of the camera.





Checking Flosh Synchronizolion
                                                              23

General lnformation

COLOR FILMsi
Because the light from the Modeling Slave Strobonar is approximately
the same value as noon daylight, the Slave is ideally suited for use
with daylight color films without corrective filters.

EIrPOSUBE!
Proper exposure requires that the important shadow areas of the
subject be exposed enough to afford detail in the final print. It also
requires that the highlight areas shall not be "blocked up" by too much
exposure. Check the recommended exposures by making actual tests.
To achieve proper exposure, make your first test exposures using the
technique suggested. The results should be satisfactory, but for the
very best results, make some exposures at a smaller lens aperture and
some at a larger aperture. Then determine the exposure index or
guide number which will give the best exposure with your own
equipment and processing combination.
    Photography of the highest order of technical perfection requires
careful control of all the variables that enter into equipment, supplies,
and techniques. If you do your own processing, it is suggested that
your techniques be standardized and you become familiar with your
supplies and equipment. In this way you will be able to produce pic-
tures of the highest technical quality. If photography is a casual hobby
to you, as to most people, remember that excellent pictures can be
made by reasonably following manufacturers' instructions.





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