Minox guide — part 1 Product booklet

I



             AN EXTREMEMINIATURE

         The Minox camera is probably the most originai and unusual
      camera ever designed. At  first sight  it seems so small and in ap'
       pearance so unlike a camera that one is hardly inclined to take  it
        seriously. One has to examine the results to be convinced that  it is
       not a good looking toy, but an efficient precision camera in its own
         right.
                                               'Walter
          As long ago as 1934 its designer,       Zupp, set himself the
       task of producing an instrument so small and light that  it could be
       a constant companion like a pocket lighter or fountain pen. IIe
      envisageda camera that would be easy to handle and could produce
        resultsequal to its bigger conventionalcounterparts.
             In 1936 the result of his work, the Minox, was produced by a
       large electro-technicalmanufacturer in  Riga, Latvia, and up  to
      1939 over 17,000were sold.
           Since 1945 the Minox has been produced in Wetzlar in West'
       ern Germany.


      The Cqmerq
          The Minox  is a sub-miniature camera measuring 37/s X I%
      X % inches (9.8 X 2.8 x 1.6 cm.) and weighs 3la  ounces (92
      grams).
          The lens is a 4-component5/B inch (15 rnm.) Complan anas'
       tigmat  I  3.5 with a focusing range from B inches (20 cm.)  to
         infinity.
          The built-in shutter has speeds of. L/2, L/5,  I/rc,    If 20, I/50,
       L/I00,I/200,I/500  and 1/1000 second,as well as B and T settings
      and has a built-in flash contact.

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The negativesizeis B X 11 mm. (5/16X7/16   in.). The carnera
 takes daylight loading cassettes holding 50 exposures (36 expo.
 sures in the case of certain films including color). The film trans.
 port is coupled with the shutter tensioning mechanism.
    The optical direct vision  finder features a suspended frame
 system,and incorporates automatic parallax compensation.
    Two filters, a green and grey (fOX neutral density) are built
into the Minox B; the  III S has green and orange filters built  in.
A depth of field indicator is engraved on the camera body next to
the distancescaleon the focusing knob.
    The Minox B has a  built-in exposure meter coupled to the
shutter speed setting controll the III S does not have this feature.

The lens Feqtures
    The aperture of   I  3.5 was chosen because at  tbis opening
the maximum image quality is obtained and an adjustable aperture
could be dispensed with. The adjustable aperture normally has
the functions of increasing the depth of field and removing residual
faults in  the lens. In  the Minox  depth  of  field extends already i
from 6 feet ro infinity.

    The curvature of  field has been turned to advantage in the
mechanical construction of the camera. The film does not  lie  flat
but in a slight bowl shape where  it  is held by a  slightly bowl
shaped pressure plate. This  is machined to the same high degree
of accuracy as the lens. While the film  is being advanced, the film
transport system lifts the pressure plate clear of the film, so that
the film does not touch anything during transport. When the cam-
era is ready for the next exposure, the pressure plate again holds
the film firmly against the curved film track.
    This measure permits  big enlargements of Minox  negatives
without stopping down, particularly as the Minox  enlarger (page
78) also has a curved film track in the negative carrier. With an
ordinary enlarger which holds the Minox negative flat enlargements
of more than 12 diameters should not, however, be attempted.

ilI   nllilOX  l.Ett  Al|D  tDlDll
    -\5rs\-';{l$





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onorligmcl which hnr born duignrd   to givo  itr maximum drinition   in thr cuwod
iln  plono.





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oppcorr proiccrcd iilo  thc vicw. Thr fromc pcrmitr  ot  lht  romc timc obrrvotlon
of rhc rurroundingr.  For cxtr.m.   clorc-upr  ot  lO  to 8 inchcr rhc  lirnirr  of  fhr
rubico  ficld covcrcd on thc ftlm lio c fromc width wirhin thc whitr  linr.





  Thc  findcr    ir  sutomolic.
olly  corrccted for  porollox
by mconr of o coupling to
tho  dirtoncr   rotfing  hnob,
ond  pivolr  lolcrolly  in  thr
dirrclion  of  rhc  lenr whrn
odiurting thc dirtonco from
inffniry lowcrdr    t  inchrr.

                                                   ,
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The Minox lens is recessed into the camera body so that the
         part of thg body shell in front  of  it acts as an efficibnt lens hood.
      Two filters are fitted to a sliding rod and built  in front  of the lens
       and can be brought into action at will. An  ultra-violet filter in the
         front  protects the camera lens and  filters from  dust and atmos-
        pheric influences. Both the lens and this protective glass are coated.

           The viewfinder shows the  subject within  a  clearly defined
        white frame which appears projected into  the view. The frame                                                                                                  -'--=
        permits observation of the surroundings at the same time, thus
        enabling the photographer to watch the view immediately outside
         the actual picture area. The finder  is coupled with  the distance
         setting, thus yielding a parallax-free image;  the  field shown  is
         correct at  all exc€pt the closest settings. Spectacle wearers will,
         find that they can see the bright image easily and clearly. The illus-
         trations on p. 7 show framing for  all distancesfrom  Inf. to B in,

        the Mechqnicql Feqtures
                All scales of the Minox are grouped side by side on the top
          of the camera and are easily operated with the tip of a finger, even
         with cold fingers or when wearing gloves.

           The shutter of the Minox  operates in  front  of the lens and
       opens fully at every speed. The shutter blades are only about L/750
        inch thick. All speedsfrom L/2 to 1/1000 second as well as B and T
        are set by a single knob.

            Closing and opening the camera automatically winds the film,
        tensions the shutter and advances the film counter. This prevents
        double exposures.
           The carrying chain supplied with the camera is provided with
         suitably spaced beads for the accurate measurement of the more
           critical closedistances (8 inches to 2 feet)

       The Minox Modeb
          The original Minox was introduced in 1936. Basically, it was
         of the same design as the present model, but  it had a steel body,

                                                                I

h.

direct vision finder, and only one built-in  filter. The multi-sprocket
film  transport was replaced by a three-sprocket wheel in  1938.
    The completely redesigned post-war Minox, made of  special
light-weight alloys,"was put on the market in 1949. It had an im.
proved lens and shutter mechanism, better viewfinder, two built-in
filters, and a measuring chain.
     In 1951, the optical system of the Minox was brought to  its
present perfection in a new model which also has further  refine-
ments of the shutter, the extremely brilliant new viewfinder with
parallax correction, and automatic filter return.
    The Minox   III  S, with  internal flash-synchronization,was
introduced in 1954.
     In 1957 a "Private Eye" model of the standard Minox  with
body finished in black was announced.

    Many Minox  users prefer  this unobtrusive finish  for  candid
work.

     In l95B the current standard model, the Minox  B, appeared
with a photo-electric exposure meter built  into the camera body,    'coupled
and          to the shutter speed setting. The orange filter  of the
III S was replaced by a IOX neutral density filter. The exposure
meter of the Minox B  automatically compensates for  this  filter
when it  is put into place. It  is available in both chrome and black
models.





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HANDTINGTHE MINOX

             Let us take it for granted that we have a Minox camera and a
       Minox film in front of us. Our first task is to load the camera. This
        should be done in subdued light;  even the shadow of one's own
       body will do.

       Loading the Stqndqrd Model
              1. Set film counter to red dot.
              2. Pull out camera.
              3. Slide open back cover.
              4. Push back camera 1/B inch.
              5. Drop cassetteinto film chambers.
              6. Close back cover.
              7. Push in and pull out camera twice.

         1. Before inserting the film, the film counter has to be set to the
            red dot, which is situated between 50 and 0. To do thiso repeat-
             edly open and close the camera with a pull-push movement (a
            "pumping"  action), until the red dot comes to lie opposite the
             black indicator mark in the film counter window.
       2 and 3. Pull out the camera shell and turn  it upside down. Depress
             the crescentshaped lock with the finger-nail of your left thumb,
             while pulling open the back cover slide with the right hand,
                until both film chambers are uncovered.
         4. Now push back the camera body by about l/B  inch. The lock will
               just start to disappear but the film chambers must be still fully
            uncovered.This action will open the film gate.
         5. Place the Minox  film  in  its  cassette over the  film  chambers
             with the film towards the back <if the. camera and the hollow
              part over the transport spindle. It  will then drop into the cam-
            era easily.
                           toIt

lOADINO





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coYcr.
  Ccalct row: 4. Purh bock corncts l  in. S. Drop corcttc  into fthn chombor. 6. Clorc
back covor.
  Sorton;  7. Purh in cnd  pull oul cotn.to  tvicr.
                                        tl
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6. Fully push back the back cover.
7. Open and close the camera (pull out the body and push  it back
    again into  its shell twice). This will wind  ofi the first fogged
    and trimmed piece of film and advance the film counter to 0.
     In the rare event of the film take-up core resting on the teeth
of the transport spindleo the back of the camera will not close. In
this case open the camera again fully, and push back until the film
gate opens. The cassetteis now re-inserted; then proceed as under
6 and 7 above.
   When unwrapping the  film  cassette from   its  packing, care
should be taken not to bend the bridge connecting the two parts of
the cassette,otherwise it might causeloading or transport difficulties,
    For 36 exposure rolls loading is the same as for steps I through
7 describedabove.

looding the Minox B
        l. With camera closed set the A.S.A. index by turning the
        shutter speed dial until the A,S.A. index for the film in use
          is opposite the film speed pointer  (solid triangle A  ).
     2. Open the camera back.
     3. Turn the shutter speeddial to 100 (red dot).
   Now proceed with loading in the same manner as for the stand
and Minox (seep. 10).                                                                                                                                  .f
                                                                                                  II
Holding the Minox                                                                       a4
    The beginner with the Minox  is likely  to lose more pictures
becauseof incorrect holding of the ca.merathan through any other
single cause! Time and again, when examining Minox  negativer
one can observe that part or even the whole image has been ob
scured by a finger placed in front of the lens, or the brim of a hal
covering part of the camera front.
    The first and foremost rulq in holding the Minox  is therefore'
keep the front of the camera clear.

                            l2

:

                                                                                                                                                    j
    For horizontal photographs hold the camera with both hands.
The thumbs of both the right and the left hand support the camera 'rom
     underneath, the index finger of the right hand is placed over
the release button, while the remaining fingers of the right hand
and the left index finger hold the top of the camera. If they are al.
lowed to wander away frorn the top there is a very good chance.thar
orrc of thein may obstruct the lens. The other fingers of the left
hand are folded,in towards the palm of the hand.
    For  vertical photographs use the same hand positiono only
with the camera turned upright.
     Practice hplding the camera in  front  of a mirror,  which  will
soon reveal if and when the lens is obstructed.
        tt  is obvious that the camera should be held as steady as pos.
sible, as the slightest shake, even if not seen in the original negative,
will become visible on enlarging.
   A  particularly  steady hold  of the camera is necessary when
working with speedsof I/20 second and longer.
    To reduc"lth"  risk of shake it  is advisable to steady the Minox
against your face and to stand with your legs apart. The shutter re.
lease of the camera is exceptionally smooth, so that only a gentle
squeezeof the ielease button  is required. The grip on t-he camera
should remain steady; but not cramped.
    For slow exposures with the cameia held in the hand rest the
elbows, or at least lean the body, against some support in order to
avoid shake. Ir,i this way I/LO second and, with a very steady hand,
even L/5 second can be exposed without noticeable camera shakp.
    Use of a tripod  is necessary when taking time exposures, and
is also recommendedfor speedsfrom L/L0 to I/2  second.
   A special tripod adapter and pocket tripod have been designed
for the Minox (pages 65 and 66).
    'When
         making time exposures and also when working with slow
speedsoI L/fi  second and slower, a tripod, and cable releaseshould
he used. This is part of the Minox table tripod and screws into the
cable release holding arm of the Minox tripod adaptor (page 65):

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}IOIDING THE MINOX

                                                  lclt:  F.ot hodrontol
                                pictunt   thr  thumbr
                                 of  borh hondr  rup.
                                  poil thc cnrncrs from
                             undcrncolh,  lhc   in-
                           dcx fingcr of rhc right
                         hond  ir  plocod ovcr        Srcody thc  ilinox
                                 lhc  rclcosc,   llrc  rc-       ogoinst  your   focl,
                           moining  fingcrr  ora
                              foldcd in towsrdr tho
                            polm. lhe  fingcrr  of
                                                  fir     lcfi  hond  hold                                                          tuch   both   clbcwr                                thc  lop  of  lhc com-                                                               wcll  into  your  ridc,                                oro.



   tighr:  Fo:  vcrticol
photogropht     rcloin
tho ronr  hond Pori'
lion nr for horirontol
on.3  but  wirh   rhc                               ond rtond with youl
cotncrq  lurncd  uP-                                          fecr  rlighrly  oport
rlghr.  lclow:  Whrn
holding  rho   llinor
lokr  corc not to ob.
rcuro thc lcnr with c
fngcr  or thc brim  of
thr  hcr.




                                 Bclowr  Whcncvcr   po:riblc   aupport  yout  body
                               ogoinst romething rolid ruch ol o fcncc, woll,  lrcr
                           o? prop your clbowr  ogoinst your  knccr,  porticu'
                                       lorly wirh dow  rprcdr. Usc o coblc rclrs:c  for  tinr
                              cxpoturc3 from g rripod.
  K*^4            ff
                         t4

Shooting with  the Minox
      Practice the steps described here, first without  film  in the cam'
 era, so that in time they will become practically automatic.
     Load camera with film.
      1. 'Pull camera open.
      2. Set distance.
 .     3. Set exposure time.
      4. Determine picture in viewfinder.
    .   5. Release.
      6. Close camera.
     The loading of the camera is described on page 10.
-  1.  To  pull the camera open, hold  it with the thumb  of your  left
     hand on the speed setting knob and the middle  finger under.
      neath. The thumb and index finger of the right hand holds the
     movable outer  shell similarly.  Pull  the  shell away from  the
     main body as far as it will go.
  2.  The distance is set on the knob in the center of the camera top.
      Place one finger on the milled center of the knob and turn   it,
       to set the distance required opposite the index mark. This is a
      black spot in the center of a short line (on the opposide side to
      the film counter). The distance scale carries the fol.Iowing set'
       tings: €   (infinity\,  6,3,  2 and LL/2 Ieet, 1 foot, 10 and 8
      inches. Minox cameras calibrated in meters carry settings of
      e  , 2,1, 0.6, 0.4, 0.3, 0.24, and 0.2 meters.
           . Between the settings for  infinity  and for 6 feet (2 meteis on
      metric cameras) is a red dot which represents a distance set'
       ting  of. L2 feet (4 meters) intended for zone focusing or snap'
      shot setting (see page 28).
        While the distance is normally estimated, for short distances
     between B inches and 2 feet the Minox measuring chain can be
      used. This carries beads at distances which corresPond exactly
       to those engraved on the distance scale of the camera. With the
      chain locked in the camera and stretched tight'  accurate meas'

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urements at B and 10 inches, and LL/2 and 2 feet can be made.
     This last distance is represented by the full Iength of the chain.
     on cameras with a metric scale the correrporrdirrg figures are
     0.2,0.24,0.3, 0.4, and 0.6 meters.
 3.  The shutter controls the length of time during which the light
     ispermitted to act on the film (see page 33). The shutter sp""d
      dial is situated on top of the camera above the viewfirrd"r.  It
       is most conveniently set by placing the thumb on the knurled
     surface of the knob and turning the camera until the required
     exposure time is opposite the black dot on the rim of the knob.
    The engraved figures 2, S,  I0,  20, 50, 100, 2A0,,500, 1000
 stand for fractions of a second,and therefore mean L/2, r/s,  L/r},
 L/20, L/50, r/r00,  r/200, L/500 and l/1000 secondrespectively.In-
 termediatespeedsmay be set, for instance: L/7s second is obtained
 by setting the shutter speedknob so that the black index mark is half.
way between 50 and I00.

                                                        sHooilNG





  lop  rcw:  l.  Pull corn.ro oprn. 2. Sot dirtoncr. 3. Sot rxpoturc  limc.
  Eollom row;  f. Dotrrminc picfurc in vicurfindor. 5. loloor   gontly. 6. Glol  coiro?e
ond oprn cgoin  lo bo rcody for thr  nrxt  oxporur..

                                                                        I A

For longer exposure times than l/2  second, the B setting on the
knob is used. In this position the shutter remains open as long as
 the release button is depressedand closeb L/2  second after you let
 it go. For long time exposures of several seconds, the T setting is
employed. Hereo pressing the release button and letting  ,it go opens
the shutter;  to close the shutter again the reldase has to be pressed
a second time. These long exposure times are best made with the
camera on a tripod and with the aid of a cable release (see page l3).

4.  The viewfinder is a direct vision optical suspendedframe finder.
        It shows a white outline framing  of the subject area covered.
     This white frame is fully  visible even if you wear glasses.The
     finder  is automatically corrected for  parallax by means of a
     coupling to the distance setting knob, and pivois  laterally'"in
     the direction of the lens when adjusting the distance from   il
      finity towards B inches.

      The picture area remains eorrect for distaneesfrom oo down
     to  I  foot. For extreme close-ups at r0 to B inches, the subject
      field covered on the film  lies a frame-width  within  the white
    frame.

D.  The release is efiected by gently pressing the release button on
     top of the camera. speeds from T/20 to r/1000 second are in.
    stantaneous and can be taken hand held. However it  is advis-
    able to take great care to release particularly gently and hold
    the camera really steady when using speeds slower than r/100
    second.

6.  To close the camera, push the shell fully back into the camera
    body. If the camera is in the pulled-out position and you are
    not certain whether the frame behind the lens has been ex-
    posed, look  into the lens window.  If  a small white circle  is
     visible there, this indicates that the shutter is set and the cam.
    era ready for exposure. If no circle is visible, close and open
    the camera to advance the film  for the next picture.  (Earlier
    cameras have a black circle.)

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Shooring Action
    Fast action aubjects such as sports call for high shutter speeds,
otherwise the  picture may be  blurred.  Under  unfavorable  light
conditions-when  slower speeds are called for-fast   motion can be
arrestedby applying some professional tricks.
        It is easier to stop motion of a subject moving straight towards
the camera or at an acute angle than  it  is to stop a moving subject
taken at right angles to the camera.
     In many sports and other  activities the movements include a
"dead point" with the subject stationary for an instant just before
reversing its direction of motion. Watch out for  this:  for example,
a swing at its highest point before it swings back, or a tennis player
during serving when the ball is at the peak of the toss. Even I/20
second will stop such a movement, if the shutter is released at the
right moment!
     For  sharp  pictures  of  fast movement of  races-car'   speed'
boat, skiing-use   this  trick: keep the car, boat, etc., in the view'
finder, follow  its movement, releasing the shutter while moving the
camera when the subject is nicely in the center of the finder. The
background  will  be blurred--enhancing  the impression  of  fast
m.ovement-but the subject will stay sharp even with exposures of
 L/50 second. Needlessto sayo some practice is required to get good
 results every time.

Sequence Shors
     Action sequencesof shots in rapid guccession are quite easy to
 take while holding  the camera at eye-level. After  each shot close
 and open the camera with the right hand and then release with the
 left index finger. In  this way up to 2 exposures a second can be
made to show changing expressions on a child's face, arrest the
 various stagesof objects in motion, etc.

 Unloqding the Minox
    As already mentioned, the Minox takes 50 exposures on a film,
 or 36 exposures per cassettedepending on film type. The film counter

automatically indicates the number of exposures. After having taken
all exposures, the Minox cassette is removed from the camera and
replaced by a new film. Both these operations should be carried out
in subdued light.

        I. Watch the film counterl No. 50 or No. 36 in some cases is
        the last exposure.
     2. Close and open camera twice.
     3. Pull out camera again.
     4. Slide open back cover.
     5. Push back camera 1/B inch.
     6. Remove cassette.
     7. Reload or close camera.

 I.  Do not advance the film beyond the red dot (or No. 38 for 36
    exposure film),  as the film might be pulled entirely into the
    take-up chamber of the cassette.This could result in fogging
     the film end by  light  entering through the light  trap  of'the
     cassette.
2. See under loading, No. 7, page L2.
3. Seeunder loading, No. 2, page 10.
4. See under loading, No. 3, page 10.
5. See under loading, No. 4, page I0.
6.  Turn  over the opened camera. The cassette will  drop out on
     slight tapping. Alternatively the cassette may be lifted out of
     the camera by its bridge.
7.  Reload the camera as instructed under loading, page 10. After
    a S0-exposurefilm the film counter should at this stage of the
    proceedingspoint automatically at the red dot.

Chonging Pcilly Exposed Films

     Occasionally you may want to change a partly exposed film,
 for example when you would like to take some color shots while
 you have a black-and-white film  in the camera. Or in poor light a
 fast film may be required, while a slow one is in use.

    To change partly exposedfilms proceed as follows.

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UNTOADINO





  7op row:  l. Wotch thc film counlcr, No.50  is thc  lorl cxposurHt   36 In fhc
Gotc of ccrloin filmr. 2. Open ond clolc cqmero lwice. 3. Pull out csmcro ggoin.
  Ccnier row:  4. Slidc opcn bock covrr.  5. Purh bqck comcrq  I   in.  6. Tip ouf
cotSctfc.
   lottcm:  7. Cloro clm.lc   ot  t lood.
                                            tn

1. Close and open camera once after the last exposure taken
       on the film to be removed.
     2. Removethe cassetteas when unloading.
     3. Note number now shown on film counter.
     4. Insert a fresh film into camera.
2.  Seeunloading, Nos. 3, 4,5, and,6, on page 18.
3.  Make a note of the number on the cassette for future reference.
4.  See loading, Nos.  I  to 7 on page 10 (including resetting the
     film counter to the red dot).
    The camera is now ready to be used with the new film  in  it.
   To reload the partly exposedfilm:
     1. Set film counter.
     2. Load cassetteand advancefilm.
l.  Set the  film  counter three numbers below  tlre number noted
    on the cassette as exposed. If,  for example, the cassettehad
    been removed at No. 30, set the counter to 27.
2.  Insert the cassette as instructed under loading Nos. 2  to  6,
    Then close and open the camera three times to take up the
     film slack
    The camera is now ready for the next exposure.
    Occasionally the question arises of cutting off exposed poxtions
of the film. In our considered opinion this is, for  all practical pur.
poses,not adaisable.

    The reason for  this  is the appreciable risk  of finger-marking
and otherwise damaging the exposed part  of the film, even when
handling it with the greatest care. l,eaving an end sufficiently long
to handle the film  in processing, in addition to the leader required
for the remaining  film, accounts for  the loss of about 6 picture
frames. On top of all that, the very intricate work required in open.
ing the take-up chamber of the cassettein complete darkness, dis.
engaging the film from  the center spool, reattaching the remain.
ing film correctly to the center spool, closing the cassettechamber
and re-sealing it, should provide a sufficient deterrent to the most
economically minded-even  against attempting  it  just once.

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.            MINOX FIIMS
    The Minox  takes a 9.5 mm. wide unperforated film  up  to
75 cm. (29Y2 inches) long, in a special double cassette.One com'
partment acts as the feed cassette,the other as a take-up cassette.
The two sectionsare joined by a bridge.
     This Minox  cassette can be loaded into and unloaded from
the camera in subdued daylight. The cassette is not designed for
reloading. The  film  is supplied in  light-metal, tape-sealed boxes
about half the size of a match box, containing two cassettesof
negative film  (ot  one  of  color  film),   individually  packed and
labelled.
   A range of black-and-white and color films are available in
Minox cassettes.
    The normal black-and-white films are panchromatic emulsions
which are sensitire to practically  all the colors of  the spectrum
from violet to red. They produce a fairly  true rendering in black'
and-white of the tone values of the subject. Some particularly  fast
panchromatic films are oversensitive to red and  will  render this
color too light.
    The orthochromatic document film  is a slow'speed emulsion,
not sensitive to red, of high  brilliance and contrast, and of par'
ticularly  fine grain. This  is intended for copying black-and'white
line subjects, books, drawings, ledgers, etc., but  is unsuitable for
anything containing half-tones.

Film Speed
    The overall sensitivity of films to light  is expressed in various
scales, such as Exposure Index numbers (also referred to as ASA
or BS Index), Weston, Scheiner, DIN  degrees, etc. Scientists and
manufacturers all agree that none of the methods employed to de-
termine the speed of films is entirely satisfactory, and continue to
give preference to one or the other of them.

                      22

The films supplied in Minox cassettesare labelled with  their
speedexpressedin A.S.A. Exposure Indexes.
        It has to be borne in mind that, although speed is a very ob.
 vious asset,it is also a quality which has to be paid for by possible
 disadvantagesof the material in other respects. To call the fastest
 film the best would be just as foolish as to select a racing car for
 daily driving.

 Grqin
     Silver grains themselves form the picture in the emulsion. To
 the naked eye they form a compact, dark mass, but under the mag.
nifying glass or microscope the separate clumps of grains are vis.
 ible. obviouslyo if the grain of our film  is coarse, it  will soon be.
come visible on moderate enlarging. The  finer  the structure of
grain, the more enlarging  it  will  allow without showing any un.
pleasant granular effect in the print.  In view of the high degrees
of enlargement required  of Minox  negatives to  yield reasonably
large prints, fine grain  is therefore important. As a rule, the grain
size is more or less in direct relation to the speed of the film. The
faster the film, the coarser the grain and vice versa.
        It may be pointed out at the same time that the grain can, to a
certain extent, be influenced by  development (hence fine grain
development), correct exposure (overexposure increases grain),
choice of paper, when making enlargements, and processing and
enlarging technique in general.

Grqdqtion
    Each film has  its characteristic way of reproducing various
degrees of brightness of the subject. If a film yields an image con-
sisting of only a few sharp steps of gray between black-and-white.
we speak of a high contrast or hard negative material. If   it  is able
to reproduce many delicate shades of gray between black-and-whitc,
it is known as a low contrast, or soft film. Generally speaking, ,ow
speed films of fine grain possessa higher contrast than fast films,
which are softer.
               n                        www.orphancameras.com

Lqtitudc

     Latitude  is the ability  of the film  to yield usable negatives,
even with a certain amount of under- or (more often)  over'expo'
sure. Films praised for particularly wide latitude may facilitate ex-
posure, but are likely to have less revolving porver, causing loss of
definition which in big enlargements is just as unpleasant as grain'
                                                                                                                     :iness.
                                                                                                                                                                                                    I
    Negative materials have a number  of  additional properties          1
which help towards good  results. There  is a  special protective
coating-a  hardened gelatin layer on top  of the actual sensitive
layer which protects against scratches. The base is colored, as a
rule gray, in order to avoid reflection of the light coming through
the emulsion and thus causing halation.

The Minox Film to Cho6se
    As the Minox  negative' is extremely small  it  is best to use
slow speed films  of  fine  grain and high  resolution. Remember
 also that the Minox camera always works at the fixed aperture
 of  I 3.5, so that with a fast film  in  brilliant  light you might need
 to use the 10X neutral density filter  to cut the light entering the
camera sufficiently to use the shutter.
      Finally a slower speed film has a greater acutance as com'
pared with a faster one, which  wilt  almost regularly  result in a
sharper appearanceof the picture.
     Slow speedfilm,2s  A.S.A., is to be recommendedas a general
 purpose film  in the Minox  under good light  conditions.  It com'
 bines fine grain and good gradation with a speed which even on a
cloudy day permits instantaneousshots.                                                        :
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     II
    Medium speed film,s0  A.S.A., is a material for any type of                               I
                                                                                                                                                                                                                                                                                                                                                                                                       Iphotograph and most  light  conditions.  It  is the fastest material                                         Ii
advised for  obtaining really sharp enlargements to postcard size                                                4without too disturbing grain.

                                                                                                                                                                                                                                                                                                                                                                                                       !
     Fast films, Plus-X (ASA 200) and Tri-X  (ASA  400),  are                    J
                    24