BEWI Super meter User manual

Cover with                                   DIN/ASA setting knob       dome-shoped diffusoro
         Diol-pointer setting ring          DIN/ASA film speeds

       Aperture figures                   Diol pointer                   ooo
        Shutter speeds                       lndicotor pointer       @@oo
       Cine running speeds                Botlery lesting mork       @
        Light volues                         Eyelet for cord       @@o

Setting the film speed
A knurled knob (71 is locoted in the centre of the plexigloss disc
over the scoles. By pressing onto it with the thumb, turn the film
speed disc until the required DIN or ASA figure (8) in the cut-owoy
portion shown is opposite the orrow.
DIN :  block bockground with white figures,
ASA :  blue bockground with white figures.
As to the film speeds which correspond to the dots between the film
speed figures, pleose refer to the toble on the lost poge of  this
booklet.
Determining ond setting lhe vclues for exposure
Open the protective cover (l) in front of the photo-resistor (CdS cell).
This initioles the light-meosuring oction. Whe.n the indicotor pointer

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(10) hos reoched o position corresponding to the intensity of light,
turn the lorge smoke-grey ring (2) with the thumb (one hond is oll
thot is needed) until the red diol pointer (9) is exoctly obove the
indicotor pointer (10). This completes the light meosuremetrt.
The volues for the exposure ore set opposite eoch other. The result
is reloined ond con be checked loter.
The upper scole (3) gives opertures of f/'l lo I/45. The lines between
these give the intermediote operture volues (holf-stops). These corre-
spond with the old operture scole ond indicote the following opertures:
f/1 .2  I/1.6 f/2.2    f /3.2 tt4.5 t/6.3 ilg     f 112.5 f/l8       f /24   f /36
The figures below the operture scole indicote the shutter speeds (4)
                                                1/rooo second.from                  nort to
                               -.,
                                                                            7

The figures 1000 to 2 ore froctions of o second; the figures l" to 30"
 (two. short strokes) represent seconds; the figures I' to 30' (one short
 stroke) represent minutes; ond I h is I houi.
The lines odiocent to the figures indicote the following older shuiler
speeds:
                         1/goo 1/roo l/so rlzs 1/ro sec.
The figure scole (5) denoted clNE indicores the running speed for
cine comeros in fromes per second. The mork between l6 ond 32
corresponds with 24  f . p. s.
There olso oppeors in the cut-owoy section (6) obove the knurled
knob in the cenfre o light volue figure; this corresponds with the
volues found on mony shutters in oddition to lhe speeds ond oper-                                                                                                                    Ilures. The dots between the light volue figures indicote intermediote
vo  I ues.
Try reoding the meter os follows, ignoring the position of the indico-
tor pointer (10):

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 set lhe film speed ot l8 DlN. Turn lhe rorge knurled setting ring (2)
 to the left os for os it will go. The figure -3 then oppeors in the
   f ight volue window (6). This figure corresponds with the meter
 reoding when the light is very weok. speeds ond opertures ore ro
 be found poired from 8 seconds ot fll ro I hour ot f/22.
 ln oddition, r/rooo second is to be found below tt45. These volues
connof, of course, be employed  in moking on exposure of minimum
 lisht.
 lf the setting ring (2) is turned to the right os for os it will go, the
light volue l6 will oppeor in the window. This votue represents
extremely bright light. Hence only the shorlesl exposure times given
(t/rooo to tln  second) con be used for the exposure. The speeds
4' to I hour connot be employed in this exlreme cose.

The meter is reod in the some woy when higher or lower film speeds
ore used. When, hoving meosured the light, you ore deciding which
combinotion of shutter speed ond operlure lo use, it is importont to
beor in mind thot smo ll  discreponcies between the octuo I  shutter
speed, operlure or film speed ond those given on the comero or
with ihe film moy give rise to incorrect exposure. Test exposures
should therefore be mode to ensure thot the BEWI SUPER, your
comero ond the film you normolly employ oll combine to produce
the best results. You will soon discover whot corrections ore
necessory if you moke one exposure with the settings os given by
the BEWI SUPER, one exposure with the operture one stop smoller
ond one exposure with the operture one stop wider. In some coses
the film speed setting os determined by o test exposure moy be
different from thot given on the film corton, ond here it  is the
former speed thot should be set on the meter.
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Upper port                          Lornp for reoding the meler
                                (The illustrotion represents the
                                reoding lomp with its vorious
Keyplote                              components.)
Upper contoct             A smo ll pocket lomp is pro-
                               vided with the BEWI SUPER.
Rubber ring                              Th is is very usefu I in setling
                         ond reoding the volues when
Peririx boltery 246                  the light is very weok. The
                             lomp is switched on by lightly
Lower contoct                           pressing the keyplote covering
                          the bottery comportment.  lt
                              gives o continuous light ofLower porl
                 www.butkus.us                                                                                                            1'.|

ubout 5 minutes, ond ofter one or two hours the bottery is ogoin
oble fo give light for o short period. A doy loter it ogoin hos the
originol power.
The Pertrix Steel Cell No.246 os ovoiloble commerciolly is used os
the source of current. This is copoble of olmost complete regenero-
tion ond hos o life of o yeor ond more in normol use. The boitery
ond bulb ore locoted between the two holves of the cosing ond if
the lotter is opened by meons of o knife they ore occessible for
renewo l.
Reflected lighf medsuremenl
meons meosuring the light which is reflecfed from the subiect to be
photogrophed ond which comes within the ongle of occeptonce of
ihe meter, which in the cose of the BEWI SUPER is obout 35o. The
meosurement is mode  f rom the position of the comero, with the
meter pointing towords the subiect.

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 Th9 intensity of the light dEpends on the noturol brightness ond
 colours of the subiect t9 be photogrophed. The exposure meter gives
 on overoge volue for the light ond dork ports of the picture.
When there ore greot controsls between righf ond dork, it  is the
 light from the importonf ports of the pictureJhot should be meosured:
 these ore, in the cose of block-ond-white photogrophs, the dork ports
ond in the cose of colour photogrophs, the light ports.
Incidenl lighf meqsuremenl
To meosure the incident light, toke the dome-shoped diffusor lying
in the protective cover ond fit  it in front of the photoresisfor.-The
on_gle of occeptonce, which hos fo be restricted when meosuring
reflected light, is thus no longer limited.
It is now the entire surrounding brightness thot is meosured ond the
result given by the meter is determined solely by the intensity of
the light ot the meosuring point. Thus ii  is not ihe light reflected

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by the subiect, but the incident light, i. e. the totol brightness of
illuminotion, thot is meosured. Incident light con be meosured from
the subiect to be photogrophed, with the meter pointed in the direc-
iion of the comero, or when this is not possible, from the comero
position with the meter pointed towords the open.
Core should, however, be token thot lhe source of light itself is not
directly meosured. Whether incident light or reflected light meosure-
ment is the more suitoble depends on the circumstonces. Incident light
meosurement is principolly employed in photogrophing inoccessible
subiects ond works of ort, ond in mocro-photogrophy;  it  is olso
                                                                                                                     isused where fhere is o high degree of controst in the sublect, os
                                                                      othe cose with, for exomple, people on o beoch or houses in
snowy londscope. Alwoys moke sure thot the some strength of
illuminotion reqches the BEWI SUPER os folls upon the subiect.

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Technicol detqils
The photo-resistor (CdS cell) hos the property of oliering its con-
ductivity in occordonce with the light reoching it. Depending on the
brightness of light present, the photo-resistor regulotes the current
flowing from the bottery to the meosuring mechonism, ond thus
determines the deflection of the pointer. The photo-resistor responds
to even the feeblest light; this property mokes possible the ochieve-
ment of exoct results even when the lighf is minimol.
The photo-resistor will olwoys function correctly if you moke sure
thot the protective cover is open only during the octuol meosuring
time. lf you close the protecfive cover ogoin immediotely ofter toking
lhe meosurement, you will olso prolong the life of the bottery. To
protect the insirument generolly ond to ensure thot the photo-resistor
is kept completely dork, wo recommend the BEWI cose with zip
fosten ing.

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The                              '                      Mollory PX 13 botterY
is used to provide the current. This is of the mercury type.
As occording lo detoils supplied by the monufocturer, the perfor-
                                                                extrememonce of the minioture bottery fluctuotes considerobly of
temperotures, we recommend you to protect the BEWI SUPER from
such speciolly high or low temperotures. During the winter, for
insionce, corry your BEWI SUPER in o pocket in close proximity of
your body ond only expose it to the cold during the comporotively
                                                         SUPERshort meosuring process. Similorly, do not leove your BEWI
                                                         meosurement.in the hot sond in the middoy sun before moking o
lf you comply with these instructions, you ore bound to get correct
results, even in porticulorly unfovouroble conditions.
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                       t"n"":|"!::Attention pleose !             !;T;:#:::"rt, 'J,',oJll3*,   ,
Bottery lesfing
When testing the bottery performonce, keep the
protective cover (1) closed. No ligt't m-ust be ollo-
wed to reoch the photo-resisior. Firmly press in
the cover of the bottery comportment until o closed
circuit is obtoined. The indicotor pointer (10) thus
must be deflected ot leost to the lower edge of thebottery testing mork (ll).  lt moy olsc be beyond
it. lf the indicotor pointer is not deflected os for os
the mork, the bottery must be chonged. In norrnol
condiiions the boltery hos o life of obout two yeors.
                                '13Alwoys use o Mollory PX    bottery os mentioned, since the BEWI
SUPER is colibroted for use with this bottery.