MINEX Meter User manual

2. Wind windittg key A as with an ordinary
watch. If only used as a stop watch, this will
very seldom be necessary
    Keep small tinted disc on face of Nfeter  3.ovef sensitive paper until ready to expose.
  4. To bring a fresh piece of sensitive paperinto position between the two tints on exposure
                                            onedial, hold the outsicle rim of the watch in
hand ancl the milled edge ring of the Meter in                       :
the other. By turning either, fresh sensitive
paper is brought into view as required.' l\feter
                                                                  isihoutd be held in deep shadow whilst this
being                                                                       1    -Wh"ttdone           desired to make a test expostlre, ur-   5.

cover the sensitive paper, and at the moment of
    commencing to expose, press knob A. This will
     start the watch. When the sensitive paper has
    reached its necessary tint, again press A andt    the watch will stop. 'fhe length of time the
    paper has taken to discolour can then be read
     off the watch face. The large hand denotes
     seconds, and the small hand minutes. To set
I   watch again, press knob A, when minute and
    second hands will return to original positions.
)   Hold meter in darkest portion of view to be
     taken or in shadow of the body.
1    The F values printed on the dial represent,
      first, the speed valueswww.butkus.usof various plates, and,

secondly, the size of Iris or stop of the Lens.
   I'he inner circle of figures represent, in the
first p1ace, the actinic value of light, and, in
the second place, the required exposure.
  The disc of sensitized paper is for testing the
actinic light value. It is placed inside the dial
so that a sma1l portion of the sensitive surface
is seen through the sma1l aperture in  disc.
The number of seconds or minutes this paper
takes to tint to the darker colour is called the
actinic light value. [n testing the light it  is
advisable to hold the Nleter in the darker
shadows cf the subject to be photographed,
                                                                                                                     Iletting the same light fall upon it as wil
                                              t)

rllumine the view, and if this is not convenient
      it may be held in the shadow of the body.
    To ascertain the required exposure for any
    given subject, hold the Nleter as above described,
    keeping the thumb or coloured disc over the
    sensitized paper until ready to test the light.
    'Ihen uncover the sensitrve paper, and at the
    same instant press knob A, which will start the
    second hand. When the sensitive paPer has
    changed colour to match the darker tint, again
f   press knob A, and this second pressure will
    stop the watch. If the watch is now turned
    over, the number of seconds or minutes the
                                      will be founCi   paper has taken to changewww.butkus.uscolour
I

registered on the dial, and this time is the light
value. If knob A is again pressed, the watch
registers itself to correct position for the next
test. 'Ihe N{eter glass dial is now revolved by
lightly placing two finger-tips upon it until the
actinic light value number is brought opposite
to the speed value of the plate or film, which                                                                                                                       ;will be found upon the speed card supplied
with the \Ieter.                                                                                        I't  Opposite each F value on the outer ring will
be found the required exposure. For example,
the speed value of ordinary Kodak Films and
nearly all "Special Rapid" Plates is F78, there-
fore if the sensitive paper takes four seconds to
                           8

change to darker tint, the dial is revolved until
                                                thel-28 cornes opposite 4, and if the stop inlens to be used is F8 the required exposure
under normal conditions will be  r f zr part of a
secorrd, as these figures are opposite each other.
If stop t6 is to be used the expostlre will
be r/5th, and if stop F3z then it will be 3l+,
and so on.
      EXCEPTIONAL SLIBJEgTS.
  For panoramic views or open landscape with
no dark objects in the foreground, instead
of setting the actinic ligh! value against the
actual plate speed number, set it two speeds
                                               platehi$her than this, www.butkus.usand calculate as if the

speed were thrs higher figure. 'I.hus, with plate
                                           with :Y::dplate speedfOSl setF78,actinomet6rset it to Frrr.time to F6a,-or
   For sea and shy, set the actinometer six speeds
 hi$her than the actual plate speed used, and calculate as if the.plate-ipeed #"r" this higher figure.        Thus,                      plaie                 *1ir,                                    rf!,                                                                  it                                        ."t                                ,s.peed to   Frz8, or                  plate speed                *ill                           F9o,                                    set                                           F256.                                                    it to If prefer,red, the-expo.rrr" for sea and sky may
be found uy- .?l.uiating as i;;  ;;   or.ii""iy
dxposure, and dividing by from g to ro.  For    +
                                   portraitr, dark:-::Ls.rk objecrs, su.li ,i  ,r"a,rurnrture, &c., ..ji^*.?te exposdre as two figuresbelow normal- If the                     the                          ".iini"  ".r""'-ih                          IO

standard tint gives 4 seconds and speed valueuf plate is F78, use two figures below this-that
is. F56, or if speed plate is Frrr treat it as FZS.
   It wiil be seen from the foregoing clescription
that the simplicity of the instrument is not
attained by ignoring any of the factors of ex-
posure, but by the scales being so designed that
each of them represents in itself two of those
factors.                         0,rK6,,tJ  Thus, the scale of diaphragms represents :-
I'irstly, the scale of diaphragms; secondly, the    -..
speed of plate; while the time scale represents
the actinometer tirne and also the exposure in
set'onds or minutes.                          www.butkus.us
                                               II

The scales are also so divided and arranged
that, when they are set correctly for one dia-
phragm, they are simultaneously set correctly
for every diaphragm, from the largest to the
smallest.
  There are two densities of tints; the darker
one is for general use and the lighter one is to
be used where the light is very weak, such as
interiors, as it takes just one-fourth the time to
reach this tint, and therefore if this time is
multiplied by four we have the correct actinic
tint value, without waiting for the senSitized
paper to change to the darker tint.
                           T2

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_l                                Ioi            t*.,.
   I        s im pt e m e t h o d      l      lnl       r ro r in t e rio rs.
      tTse a plate or fi1m of."?'Xt64 and put the stop of lens
     at Fjz, then place Meter in the darkest portiont   cf picture 'where detail ls requireci, and when
  i    Daper has changed to lighter tint exposure will
     b: complete. If any other speed of plate is used,
 {    saine metho:l can be employed by using a stop
 I    indicated by counting four spaces belolv speeci
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