LEUDI II Exposure Meter User manual

Instructions for Using

                             METERTHE             EXPOSURE    LDI]I}I
            MODEL  II
                Made in U.S.A.
 On the meter will be found four rows of figures: To thc
left, Sfops and Filter Factors: in fhe center, Exposure Times
in fractions o{ seconds, seconds and minutes; to the right,
two rows of numerals I to 8 and fi'e fields, whlch represenl
different light conditions and whrch a'e divided into four sec-
tions each,- corresponding lo the film speeds of 12, 24. 50
and 100 Wesfon (20o, 23o, 26o, and 29o Scheiner, respecf'
ively). The light condiiions represented by the five frelds
are as follows:

           YELLOW-WHITE-BLUE-Sunlil dirlcnf landrcapc., 3now rnd
               3CC tCOnCt.
          YELLOW-WH|TE-Outdoon in runrhinc.

          WHITF-shadow or no runrhinc.
           WHITE-BLUE-lnlcrion with lighr wallr or  brighr adificicl
                       lieht.
           BLUE-lnterion with darl we lls ot  with  fow artificicl
                      illuminciion.   ffiwHffiN
  To measure wiih the LEUDI, esfablish first the light condi-
tions with regard io the five fields, as -indicated above. Thenhold the meler at reading distance from the eyes, pointing
to the subiect to be pholographed, preferably its halftones,
and look through +he lateral opening of the meter, where o
row of blue figures will appear (the figures apPear upright if
the little red or white dot on the meter is held to ihe left
                                             ^l

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       side). Note the dimmest number thot con be seen, evcn if
        indiitinctly. Sef this number on that section of the field that
       corresponds to ihe speed rating of the film you are using.
      The meter is now set, and combinations of correct stops ond
       exposure times are automatically lined up for direct reoding.
          In case of doubt which one of two numbers io use, selecf
       the dimmer one.
            lf stop and exposure iime indicated by the mefer do not
       exactly coincide with the figures on the camera scales, the
       nearest figures should be used. Always favor the longer
        exposure.
            lf a filter is used, adittst the meler in the following way:
       Find the correct exposure without filter, as indicaied above.
      Note where "No Filt." on the movable scale siands. Then
         shift the movable scale so that fhe factor of your filter will
       stand where "No Filt." stood be{ore.
        EXAIv4PLE l.  The subiecf to be faken is in sunshine. The      number seen ihrough fhe meter is "4". The film used has a
       speed of 50 Weston (260 Sch.l. Se+ number "4" on secfion
       "50" (26) of fhe yellow-whife field. Resulf: Exposure l/+.5                                                                -                                                                                         f                      f        /500, or l/8      )/ 100, or                                               /ll     l/50 seconci, etc.                    -                 -               lf a filter with a 2x factor is used, bring "2x" on the movable
       scale fo where "No Fil+." stood before. Result: +/4.5
        l/250, or {/8     l/50, or f/ll     l/25 second, efc.                     -       EXAMPLE 2. On a dull, gray day a street scene is to be
      phofographed. A wall of a house has halftones. The meter
       gives "5" as the dimmest number siill discernible. Film used
         is rafed at 24 W.esfol (23o Sch.f Set 5 on Secfion "24" l13l       of the white field. Resuh: f/4.s      l/t}, or 116.3      its,       or  f /8    l/2 second, etc.       -                 -              -       EXAMPLE 3. A dark room as ba.ckground. Reading ihe
      mefer gives figure 5. The film used ii Super XX, rat6d al
       100 Weston (29o Sch.). Set 6 on section "100" (29) of the
       blue field. Resuh:  f /4.5    5 seconds,f /6.3    l0 seconds, etc                             -                 -         Film Speeds other than 12, 24, 50 or 100 Weston. The
      LEUDI may readily be adiusted io film spocdr other fhon 12,


\r

24, 50 or l0O Weston (20o,23o,26o or 29o Scheiner, respect'
ivelv). Thus, to adiust for a speed of 6 Weston, which is hal{
as {ist as 12 Weston, set the meter first for 12 Wesfon; then
                                                                theshift the scole downward by.Forone step corresponding tosize of c section of a field.      instance: lf "4" be the expo-
sure numeral in sunshine, for 12 Weston the exposure would
correspond +o {/a.5    l/100 second: to obtain the.exPosure                    -             5 Wesion, move the scale downwardfor a' film speed of
                                                                       Similarly-,by one step, which gives I/!.5             | /10 second, etc.                              - speed twice as fast as 100if' the negative material of a
Wesfon b; used, move the scale upward by one sfep from
"100." With exposure numeral "4" in sunshine, for insfance,
this would give an exposure of f 116    l/100 second, etc.                                  -
  Motion Piclure Cameras. The LEUDI can be used with
motion picfure cameras having a frequency of 32, 16 or 8
fromes per second. The lens aperlure required is read direcl
from the meter, and is that which sfands opposite fhe fre-
quency number. The values are for a shutter of l80o opening.
  EXAMPLE. 4  Sunshine: film used rated of 50 Weston (260
Sch.) dimmest exposure numeral 3; camera used has frequency
                                                                                                                                                                                                                                                                                                                                            i32. Sei figure 3 on section "50" 126l of the yellow-white                                            I!
field. Resuli: Required aperture +/22.                                                         l&.
  The two blue fields should also be used in twilight and in
very dark woods and foresis. Just. before sunset fhe observed
fiqure should be set between the Whife and White-Blue  fields.
  For Orfhochromatic maferial the exposure time given by
the mefer should be doubled when working with artificial light.
Panchromatic maierial needs no such increase.
  When a double extension camera is used for very near
obiects to take full sized piciures, for insfance, four fimes ihe
normal exposure is required.
    lf insfantaneous exposures give over- or unCerexposure,
while time exposures are correci, then the shutter is at fault
and should be adiusied for speeds.
  Speed Raiings. The ratings'of film speeds are comparative
volues. lf fhe rating of the film fo be used is not known to