Gossen Luna-Pro sbc flash attachment User manual

The LUNA-flash electronic   f lash at-
tachment  is a true integrating measur-
ing for precise incident readings of
electronic flash output. Becarrse all of
the light from the flash is measured,
accurate readings can be made with
flash durations as long as 1 | 125thsecond o r as sho rt as 1 / 50  , 000th
second. Multiple fiash capability allows
you to accumulate readings when the
light output from a single flash is
insufficient.. The Luna-flash can be
used with or without a sync cord for
conven ience.
                                           compretely famiriar with the general                                                   procedures                                             gperating                                                                   outlined                                                                              in theNote: Before              reading the following                                    de-                                                Luna- Pro                                         or Luna- pro                                                   sbc owner,stailed       instructions,you                     should www.butkus.us                                be         fnanual.

the jacks in the meter and the recess in
                                              the attachrnent  'is opposite the hemi-
                                                 sphere. While holding the LUNA-flash
                                            by its ribbed sides, push the accessory
                                                      straight onto the meter.



                                                                                                                                                                                                                                                                                                                                                                                                            I                                  TAKING A READING
                                 The LU NA-f lash attachment is de-
                                                  signed to remain on and in a ready stateATTACHING THE METER                                                      for as long as the basic meter is on.
Remove the detachable front shield            During that period of time, any flash or
covering the accessory jack  f rom your            flashes that occur will be read. Prior to
Luna-Pio sbc. With the hemispherical          the  f lash being  f ired, the meter will
diffuser in the center of the Luna-Pro           remain in its standby mode and will not
sbc align the LUNA-flash attachment            read any ambient light. Before using,
with the front of the meter so that the          the film speed must be set into the
prongs of the attachment are opposite          computer dial of the meter.

'f;:r..,,,,/ ,i" ;' -'j,  ,., '      .
To take a readlng:                             3. Point the hemishpere (3, Figure 1)
1. Turn the meter on by pressing and         on the LU NA-f lash toward the
   releasing the power switch. The             camera or the particular light to be
  green indicator will come on. (1,             measured and fire the flash. lf de-
   Figu re 1 )                                          pired, the sync cord of the flash
                                            can be plugged into the sync con-
2, Press and release the reset button               nector (4, Figure 1) on the side of
  on the LUNA-flash attachment. (2,www.butkus.usthe LUNA-flash and fired by means
   Figure 1)                                                 of the trip button. (5, Figure 1 )

*lf ffH



4. Rotate the computer dial until the
  meter nulls. Note: the red zero
  mark on the exposu re correction
   dial should remain between the two
   red triangles on the mete,r face when
   nulling. lf the zero mark goes
  beiond either of the red triangles,
  the  f lash intensity is beyond the
   range of the meter. When past the
   right triangle, the light level is too
   low. When past the left triangle, the
   light level is too high.

5. Read the proper  f /stop opposite the
   red flash indicator on the computer
  dial. This indicator is  located
  between the 1 and 2 second expo-
                                                                                                                                                                                                           f                                                       f the one minute time period of  sure marks. Note: the meter will
  shut off after one minute unless              operation is too short, the power switch                                  can be locked on for continuous   locked on. At that time, the green                                                   operation. Always remember to turn   indicator light will go out. Do not                                              the power switch back to the normal   leave the meter on when not in usewww.butkus.us                                                       position after using the locked position,  as rapid battery drain will occur.                                                  otherwise short battery life wif l resu,r.r.,

intensities of the other lights without re-LIGHTING RATIOS                                                            nulling. The reading indicated by the
  f n addition to readings of overall light             meter needle will tell you the relative
                                                                                                                                                                                                                                            ,intensity, your LU NA-f lash can be                                                 strengths of the other lights with
used to determine lighting ratios, that               respect to the main light
is, the relative strength of each light.
Point the meter toward each' light
individually and take ,a reading.                MULTIPLE FLASH
Be sure to shield the meter from the                Occasionally, the light output  f rom one
other lights.The difference in EV values                flash of your equipment may not be
between the readings will give you the              enough to give you the  f / stop required.
f /stop differences of the   f ights.                 By repeatedly  f lashing the light with the
                                                   shutter open, you can increase theAnother very simple way to measure                                                         total light output and work at smallerlight ratios is to take a reading of the                                                     stops. The ambient light must be verymain light and null the meter. Then use
the LU NA-f lash to also read the              low and excess light blocked from the                                                      lens to do this.

null the meter. In this case it wiff be
                                                                     four. You will have to flash four tilnes to   When doing multiple flash work, it is                                                         get the proper exposure at  f 122.    important to remember that for each    f/stop increase in exposure desired,                     flvftfus,us
    you must double the number of  f lashes.                                     CHANGE OF    Therefore, if your desired  f i stop is           SHUTTER SPEED SETTING    more than a few stops away  f rom the
    indicated stop, this method becomes             Most electronic   f lash units have a
     impractical.                                                                                                                                                                                              I        relatively short duration. Therefore,
                                                                                          J        actual film exposure by the flash is not
                                                                        il        affected by changes in camera shutter                                                                                                                                          is   Example: You r indicated   f / stop is             speed as long as synchronization                                                   maintained. However, changes in       t 111. You wish to work at  t 122. Adjust                                                            shutter speeds will alter the effect of    the computer dial of the Luna-Pro sbc
    until the red   f lash index lines up_              ambient light on the overall exposure.
    opposite  t 122 (a change of two www.butkus.us(As the shutter speed changes, the           f / stops). Reset the LU NA-f lash and                  portion of the total exposure caused by
L- count the number of flashes it takes to

the flash remains constant, but the               in ambient exposu re caused by the
portion caused by the ambient light will             change in shutter speed. To determine
vary.) As long as the flash output is                  if compensation is required, two
considerably higher than the ambient,                 parallel measurements must be taken
this effect can be ignored. But when                                          f rom the same position:the level of ambient light exposu re
approaches that of the flash, attention               1. Normal measurement (flash and
must be given to the effect of shutter                ambient light) with the LUNA-flash
speeds. The circuitry of your LUNA-                  attachment
flash is designed to indicate the  f /stop             2.Measurement of the ambient light
which will produce corrgct overall                   only, using the basic Luna-Pro sbc
exposure witn a shutter' speed of                  meter with its hem ispherical diffuser
1 I 100th to 1 | 125th second. lf the                 placed in  f ront of the measu ring cell.
ambient light is extremely bright, and a              Compare the  f / stop indicated by the
different shutter speed is used, the                LUNA-flash with the  f /stop shown
indicated  f / stop may have to be               by the Luna-Pro sbc for a shutter
modified to cornpensate for variations                speed of 1l125th second. Any dif-

SPECIFICATIONS
 llfeasurfng Method
 Incident light measu rement using
 hemispherical diffuser. Single or multi-
ple flash capacity.
Measuring Range:
40 to 10,000 Lux seconds.
Measuring Angfe
1900
Computer Scafes
Uses Luna-Pro sbc scales (see Luna-
Pro sbc instruction book toi Oetails).
Power                             www.butkus.usPowered by Luna-pro sbc meter.