Burke & James No 3-A Cub User manual

JYo. 5-A
Cub Csmero





         lManufactured Bg
                     Inc.Burke & James,

www.butkus.us
    JYo. 5-A
Cub Camerg





               Figure 1



   For Taking Pictures
    3% x 5% Inches
                        I

Venmo @mike-butkus-camera  Ph. 2083
PayPal Name  Lynn@butkus.org      www.PayPal.me/lynnbutkus

lnstructions for Operating The
No. 3A Cub Camera
  Do not attempt to load or take any pictures
 with the Cub camera until you have become
 thoroughly familiar with every part of the in-
strument. Take espe,cial care to learn the con-
 struction of the shutter; work it for time and
instantarreous exposure. Read carefully the
following instructions. The most important
thing to be  . remernbered in picture ta-king is
that no white light lincluding g2s, electricor lamp light) should be allowed io strike the
film, even for a fractional part of a second,until it has been developed- and fixed. It  is
therefore best that the loading and unloading
be done in a subdued light, for after the seal
on the film is broken there is a possibility of
the edges becoming fogged if care is not taken
to keep the black paper drawn tightly.
  Before loading the camera, try the shutter tosee that it is working properly.
 The No. 3A Cub takes either the Ansco
Film No. 18A (6 exposure) or 188 (tz ex-
posure) or Eastman Film No. BA F. P. K. or
        make of  film adapted to these:l"Ir.gtltr
           To Load
 To remove the ro11 holder, felease the metal
catches "D" with the thumbs, at the same time
pushing upwarcl with the    f orefingers. (See
fig'ure 1). An empty spool will be found in
position on the winding key side. Place the
full roll between the spbol centers on the op-.
posite sicle; this is best accomplished by plac-
ing the lower flange of the spool againsf the                                        -untilbottom spring, then pushing down                                             the
upper end of the spool engages in the spool

www.butkus.us
    center. Be sure that both ends of the.spool    are engaged by the spool- cetlt-ers so that lt
     revolve-s evenly-; also see that the black q?P:,t
     trnwinds   f rom the outer side of the spool' W tth
                                                             pa-ss     the full ro11 in place, break the seal and       it"te ttact< paper over the metal rollers at the    back of camira, and thread it into the slot of
     ihe empty spooi. Turn the winding k9" slight-
     ly to secure the. parper. .Care. must be taken                                             should     tiJ  ttte paper is- started straight, for    one side beir against the flange of the spool
      ttiiOit than the other it will not wind evenly                                                  see           *itt cause trouble later. Therefore    "nathat the paper is properly centered. Through-
     out the opeiation bf loading, f.tou the-breaking
     of the seil until the camera is closed see that    the oaper is wound tightly over the spools,     for it it is allowed to loosen or bulge, there'      is a chance that the lilm will be fogged.       Replace the roll holder by entering the rear
     cornets first, this will prevent the papgr catch-
      ir* ott the sides of the camera (See figure 2)'     i6*.r  the roll holder until the side 'catches
     snap into position.





                                                Digitally signed by Mike Butkus
                                    DN: cn=Mike Butkus, o=Butkus camera
                                       manuals, ou=butkus.org,Mike Butkus email=mike@butkus.org, c=US
                                          Date: 2023.02.04 21:36:30 -05'00'

With the top in place turn the winding key
 slowly until the figure one appears opposlte
the ruby window which  signifies that the filnt
is in proper position for the first exDosure.
  The camera is now ready for making ex-
posures for all oblects at a distance of ei'ght
Ieet or more.
           The Shutter
  The shutter supplied with the Cub camera
 is automatic, that is, it is always set ready for
taking the picture-a pressure of the lever
 (A) from right to left or vice versa makes an
instantaneous or snap-shot exposure. To set
 for time, draw out the slide (C), one pressure
of the lever opens the shutter and a second
pressure in the opposite direction closes it.
         Stop or Diaphragm
   All Cub ca'rneras are supplied with a dia-
phragm plate having three different sized o,pen-
ings, which regulate the amount of light that
 is allowed to reach the film.
   - The largest operring is for making sna,pshots in bright sunlight.
  The medium opening is. for irrterior time
posures, see special directions under Time
posures Indoors.
  The smallest opening is for rnaking time ex-
posure out-of-doors on cloudy days.   Never
use the smallest stop for sna,p-shots.  See spe.
cial directions under "Time Exposures  Out-of-
Doors."
  With slide B in normal ,position the largest
opening is in place; to use the medium opening
draw out the slide until the locating spring
snaps into first indentation; to use the small-
est opening draw out the slide until the spring
snapQ into the second indention.
                       -5-

www.butkus.us

      lnstantaneous of Snap Shot Exposures
        In making instantaneous or 5p2'p shot gxpo-
      sures use the largest diaphragm stop. Snap-
      shots are usuallv tnade while holdir-rg the cam-
      era in the hand, the light should therefore be
      bright sunshine. On bright days snap-sirots
       cari be made at any tiine during the day from
       three hours after sunrise to three hours before
      sunset. Earlier or later than this short time
      exposures should be given.  It  is a good rule
      never to photograph directly toward the sutl,
      the best position being to have the light shin-
      ing from ,behind the operator or over either
      shbulder and directly on the the object to be
      photographed.  If the direct rays of the sun
       strike the lens during the exposure the picture
       will be blurred. Do not try to photograptr
     moving objects at a shorter distance that 25
         ft. disiant from the camera. It  is advisable
      to endeavor to catch the'rn at an arlgle either
     coming toward or going from the camera, as
     good rlsults will not be obtained if taken rvhen
      fhe object is  directly opposite.  If  photo-
      graphing tall buildings at. close ralrge  it   is
      necessary to secure a posltlon as near as pos-
       sible opposite the center of the building, for
           if the cartrera is tilted upwarcls, the lines in
      the picture will be found to cottverge because
      of the fact that the top of the building is of
     a much greater distance from the camera than
      the bottom. This same rule applies whetr
      photographing srnall objects such as a dog; -in       this case the carnera should be lowered to the
       center of the object to be taken, thus avoiding
      anv distortion.
       Wh"tl ready for .making the exposure hold
       the camera in both hands and as near level as
       possible so that the picture will be in true
       perspective. Locate the object irr the finder
     by looking squarely into  it making sure, that
        all of  tl're- object which you desire to photo-
                           -6-
l-     ---.-   *---J-;--

graph falls within the limits of the finder.
When all is  ir-r readiness release the shutter
taking care not to jerk or move the ca,mera
during the exposure. A' pressure of the lever
will open the sl-rutter for a fractional part of
a second thereby permitting tlie light to pass
through the lens and forming an image on
the sensitive surface of the film.  After mak-
ing the exposure turn the winding key to the
right r,r'atching the ruby rvindow in the ,back of
the camera until the next number appears.
This is a \rery important point and one should
early accluire the habit of turnir-rg the wind-
ing key after each €xposure thus avoiding the
possibility of making trvo exposures on the
same surface of the film.
         Time Exposures
 When making time exposrlres  it is absolute-
ly necessary that the camera be placed upon
a tripo.d, table or hr,m surpport where there
rvill be no danger of its being moved dr-rring
the exposure. Center the object properly in
the finder, and draw out metal slide "C." Give
a siigle pressure of the lever to open and
r.vhen sufficient time has elapsed an additional
pressure to close, using care uot to jar the
iamera in either opening or closing.
  In making time exposures it is 4ecessary to
use some jud,gment in regard to the length of,
time the lens shoulcl remain open. This  is
governed 'by the amount of light which fallsirpon the object to be photographed at the
tirne of the exposure.
    Time Exposures Out-of-Doors
  In making tinre exposurcs ottt-of-doors the
rnetal slide C should be drawtr out and the
shutter opened and closed as quickly as pos-
sible.

www.butkus.us
   WITH SUNSHINE use the smallest dia-   phragm, opening and closing the shutter as
    quickly as possible.
   WITH LIGHT CLOUDS use the smallest
   diaphragm, giving f.ron I  to one second ex-
    DOSUre.-      WI'I'FI HEAVY CLOUDS use the smallest
   diaphragm and give from 2 to 5 seconds.
      'fhe foregoitrg calcrulatious are for open air
    ex,postlres. Wher-r photographing objects in
   shadows or on porches, nc) accurate directior-rs
   can be given as too much depends upon the
    density of the shaclows. Proper exposure calr   only be learned through experience or by          t*I   using a scienti{ic exposure meter such as the
   Watkins Bee.
    CAUTION. Never attempt to make a titne                     l-.t   exposure while holding the camera in  the
   hand as a blurred picture is sure to result.
              Time Exposures Indoors
    The following table is for the largest stop.
   In case the medium stop is used twice as much
   time must be given. With the s,mallest stop,
    four times as much;
              White Walls and One Window
     Bright sun outside, three se,conds.                                                                                .Jl
    Hazy sun, eight seconds.                                                                                                                                  +I      Cloudy-bright, fifteen seconds.
      Cloudy-dull, thirty seconds.
         White Walls and More than One Window    .
     Bright sun outside, trvo seconds.
(     Hai.y sun, five secottds.
     Cloudy-bright, ten seconds.
      Cloudy-dull, twenty seconds.
        Medium Colored Walls and One Window
      13right sun outside, six seconds.
     llazy sun, fifteen seconds.
     Cloudy-bright, thirty  seconds.
      Cloudy-dull, sixty seconds.
                     -E-                                                       1.
                                                                                     Ii

Medium Colored Walls and More than One Window
  Rrigirt sun outside, fottr sccottds.
  Hazv sult. ten seconds.
  Clotidy-bright, tlventy seconds.
  Cloudy-dull, forty seconcls.
       Dark Colored Walls and One Window
  Bright sun outsicle, twetrty seconds.
  Hazy sun, forty seconds.
  Cloddy-lright, eighty seconds.
  Cloudy-dull, trn'o minutes, forty seconcls.
   Dark Colored Walls and More than One Window
   i3right sun otttside, ten seconds.
  Hazy sun, twentY se'conds.
   Clouclyrflight, forty seconds'
  Cloudy-dull, one mlllute, tr,venty seconds.
  The foregoing figures are for rootns whose
windows set lisht direct from the sky and for
any time during the day from- three hours
affer sunrise to three hours before sunset.
          llome Portraits
  In order to make portraits (large busts and
head s)  it  is necessary to use a portrait at-
tachment. For this purpose we strongly rec-
ommend the Ideal Portrait Lens, whi'ch will
enable you to make portraits of the satne soit-
ness thlt tnarks professional-mounted   work. The IdealPortrait Lens is           in a tleat brass cell
with adjustable springs and fits over the hood
of the iens like a cap. Special directions for
its use accompanies each lens.
         Removing the Film
  No dark room is reqttired for removing the
film frorn the camera. However it is best to
perform this operation in subdued light observ-
ing the following rules:
  First: When the last section of the film hasbeen exposed turn the winding key until all
of the paper has been wound on, the spool in
                    -0-

Dark Room Development
  Films may be taken to the nearest Photo Sup-
ply Dealer for development. Dealers handling
our products can be readily recognized by the
appearance of our trade-mark on their store
windows. However, in order to secure the great-
est pleasure and profit from your camera we ad-
vise that the amateur develop his own films, for
the process is both interesting and simple. The
easiest and least expensive way to develop roll
films is by using trays in a darkened room which
is lighted only with the ruby lamp, care being
taken that all white light is excluded. The fol-
lowing articles are recommended for this pur-
pose:
 An Ingento Ruby Lamp No. 6.
  3 Insulate Trays 3%xb%.
  7 8-oz. tu;nbler graduate.
  1 Ingento Tablet Crusher, or glass stirring rod.
  1 Amateur Printing Frame and plain glass.
  1 package of Ingento M. Q. Tablets.
  1 box of Ingento Acid Hypo.
  Select a room or closet where all white light
can be easily excluded. When development  is
rlone at night this offers no difficulty whatever.
The reason that a darkened room is required is
that the film is extremely sensitive to white light
and would be spoiled  if exposed either to day-
light or lamp light for the fractional part of a
second. Having provided the articles mentioned
above secure a pair of scissors, a pitcher of water
and a pail for waste.
  Set the ruby lamp on a table or shelf and light
it. The subdr-red red light which it emits will not
injure the sensitive film unless held too close to
it.  It is therefore advisable to place the lamp at
least 18 inches away from the tray in which the
developing is to be done; fiil one of the trays
with water, open the box of tablets and take two
ta,blets from the large bottle and two tablets from
                  -11-

www.butkus.us
one of the small vials: fill the graduate to the
 six ounce mark and drop all four tablets into the
 water, immediately crr-rshing them with a stirring
rod until reduced to a fine powder; then stir the
solution until the tablets are thoroughly dissolved.
Pour the contents of the graduate into the second
tray; next prepare t!e_ fixing.bath by dissolving
one measuring cup (which will be found on the
inside of the box) in eight ounces of water. Stir
until the solution is complete ; then pour thecontents of the graduate into the third  tray.
 (Note-It  is not necessary to mix the solutions
in the darkroom, as they are unaffected by light.)
  To develop the film break the seal with which
the black paper is held and unroll until the point
where the film is attached to the black paper, then
detach the entire strio of film from the l;lack





                                           L


           Fig. 5-Developing the Film in a Strip.
paper and allow the film to roll up loosely. Hold
one end of the ro11 with the thumb and finger of
the left hand and take hoid o{ the free end with
the right. Pass the film through the tray of
                     12-                           -

clean cold water holding one end in, each hand
as shown in the cut. Pass it  in this ntanner
through the water several times so that there
will be no bubbles remaining on the surface of
the film. When it is thoroughly wet the develop-
ment may be commenced. Holding the fihn in
the same nanner, pass the film through the de-
veloping solution as described for  rvetting  it,
keeping  it constantly in motion. In about one
minute dark spots will begin to appear. These
are termed high lights ancl very soon after their
appearance an irnage of the object will be dis.
cernible. Complete development in the strip bv
passing the film through the developing solution
until all the detail has been bror-rsht out in the
thinest uegatives.
   It will be noted that the negatives are of dif-
ferent density. This, however, is not an objec-
tion as this can be overcorne in printing. The
difference in derrsity does not affect tl-re difference
in contrast. Keep the strip which is being de-
veloped in constant motion allowing the develop-
er to act from five to eight minutes, depending
tlporl. the. rapidity rvith which the negatine gath-
ers derrsity. The progress of developiff-e4t. nray
be watched l;y holding the strip up to tht'lanrp
from tirne to tin-re. It is advisable, however, to
make the examination as short as possible.
  Note: To avoid transparent spots after hav-
ing passed the film through the developer the
first time face dorvn, reverse it and pass it
through face np, holding the film down in  tl-re
tray and drar,ving it lightly through the developer
under the hand. This rvill break all the air
br.rbbles. Transparent spots are caused by air
bubbles adhering to the film during clevelopment.
  After the development has been compieted, pass
the films a few times through the clear water,
then transferring it to the tray containing the h-x-
ing bath. When all of the creamy surface has
disappeared from the unsensitized surface of  tire
                     13-                            -

I                                                    I                   www.butkus.us
film fixation is practically cornplete. ,It is, how-
ever,, advisable to continue to pass the film
through the solution two or three minutes after
the disappearance of the creamy color.
  After the films are thoroughly fixed they should
be washed in cold running water from twenty
to thirty minutes. If running water is not con-
venient ten changes of fresh water should be
used, keeping the films constantly in motion all
the while. The thorough washing of the films is
very important in order to remove all traces of
the Hypo or else stains will appear after drying
and the negatives will be ruined.
  After washing, the films should be hung ttp to
dry in such a manner that it does not touch the
snrrounding objects. The place selected for dry-
ing should be free from dust. If a mild current
of air is present the process of drying will be
greatly quickened.                                                               '
 The temperature of the developing solution
should be as near as possible to 65 degrees Fahr-
enheit. The fixing bath ancl water used for rvash-
ing should be kept cold, ice being employed in
extremely hot weather.
  The use of the Ingento Developing Roller will
greatly facilitate the developing process. This
device consists of a heavy glass roller which re-
volves on two brass pins mounted in extra heavy
nickel plated brass frame. Its own weight  is
sufficient to resist the pull of the film when it  is
being drawn through the solution. When this
roller is used only half the solution ordinarily
required need be made up as the roller over
which the film is drawn is within 3/16 of an
inch from the bottom of the tray thus keeping
the film entirely submerged in less than one-half
inch of solr.rtion. It is for use in trays 4x5 or
larger and will accommodate any film a/axifu
or smaller and can be obtained from all photo
supply dealers.
                        l4-                        -


                                                                                                               -  'r;.'

Separate Development of Each Exposure
       The above directions apply to the development
       of the film in the strip. It is sometimes advisable
      to develop each section separately, especially
      where there has been' a great variation in the
        exposrlres given. In this case the following direc-
       tions apply:
        In unrolling the film preparatory to developing
       in this manner care must be taken that the end
       should not be allowed to roll up over the paper.
     The exposures should be cut apart with the black
      paper on top so that the divisions between each
       film can be readily recognized by the numbers
      which appear on the edge of the black paper. Do
       not let the fingers touch the face of the fiim. The
       face is the dull side. The proper manner of hold-
         rrg the film is illustrated lry figure 5.I



I
I

               Cutting the Film for Separate Development
        After the film has been cut into sections as
       indicated above place the sections in the tray
       containing the clear water, to remove air bub,bles,
      covering the tray with a piece of brown paper
                                        -. 15*

www.butkus.us
or cardboard to exclude the light of the lamp.
Take one of the sections from the water and im-
merse it face down in the tray containing the
developer; rock the tray gently to prevent streaks
and air bubbles. In about one minute the film
will begin to darkep, representing the highlights
of the picture and in about two minutes the image
will be discernible The common way of determi-
ning when the film has been fully developed is
to look on the back to ascertain u'hether  tl-re
objects in the picture have begun to show through.
When developing films singly, from five to six
minutes is usually required, the time varying
according to the temperature of the solution.
 When development is complete transf er the
film to the tray containing clear water and rinse
it two or three times, after which it should be
placed in the tray containing the fixing bath, At
this juncture the second section of the film should
be put through the same process, care having
been taken that none of the Hypo has adhered
to the fingers, thus allowing  it to come in con-
tact with the undeveloped section or with the
developer.
  Three or more negatives may be developed at
one time by placing the films in the developer
face down and alternating each section so as to
prevent air bubbies; however, w€ recommend          ?Jthat the beginner develop only one section at a
time until the necessary experience has been gain-       #
ed. As each successive section is developed andfixed it should be placed in the washing water.              It
After the films have been thoroughly washed they
should be pinned up separately to dry, care be-
ing taken that their surface is not allowed to
c'ome in contact with the surrounding obj ects.
  While Ingento I{. Q. Developing Tablets are
recommended, the Ideal M. Q. Developer in tubes
will also be found highly satisfactory. Complete
directions for making up the solution are printed
                        -'lo-

on each tube. For those who desire to prepare
their own developer we recolnmend the follow-
ing formula.
Hydro Metol DeveloPer.
        Water           64 oz.
           IVIetol         45 grains
    B. & J. Sodium Sulphite (anhydrous) l%
                   oz'
                                                          oz.B. & J. Sodium Carbonate (anhydrous) L    B. & J. Hydrochinon 90 grains    B. & J. Bromide of Potassium 12 grains-  The chemicals should be added and thoroughly
dissolved in the order given. From this stock
solution a sufficient quantity of developer is taken
for the work in hand. The stock solution will
keep indefinitely.
          Making Prints
  There are in general use, three classes of paper
used for making pictures. Namely, 'blue print orferro-prussiate paper, printing-out paper such as
Solio,- Disco, etc, and developing or gaslight
paper, sttch as Cyko, Velox, Argo, etc. The first
lwb classes are for daylight printing only whilethe last class may be printed either in daylight
or by artificial light.
         Printing Out Papers
  Open the printing frame and place the negative
face down upon the glass, then place upon this
a sheet of blue print paper. Replace the back
of the printins-       frame and secure it with thesprings.   It wiTl be noted that the back of the
printing frame is hinged so that a qart of the
print *uy be uncovered for inspection d-uring
printing, without disturbing its register with the
negative. The loading of the paper into the
frame should be done in a subdued light, that is,
in an ordinary room, but as far as possible from
the window. The unused paper should 'be re-
turned to its package for protection from the
light'
                        ri-                   -

www.butkus.us      rI
                                                                                                                                                                                                 I

                                                                                                                                                                             I     The loaded printing frame should be placed
      glass side up in the strongest possible light, direct
     sunlight being preferred. It  is allowed to  re-
     main until the image from the negative has been
      sufficiently impressed on the sensitive paper. This
     can only be determined by an occasional examina-
     tion of the paper. Print until the shadows be-
    come a gray bronze color, or until the highlights
     are slightly tinged with ;blue. lVhen this stage
     has been reached remove the print from the print-
     ing frame, wash thoroughly in running water for
     15 minutes or in several changes of cold rvater
      allorving the print to remain in each bath a few
    minutes. After having thoroughly washed the
      print as above indicated, it should be hung up for
     drying. The Ingento Blue Print Paper is es-
      pecially recommended as it is prepared especially
     for photographic purposes.
     When using a printing-out paper such as Disco,
      Solio, etc., the frame should be loaded as clirect-
    ed labove for blue print paper. The printing     should be allowed to continue until the tone of
     the print is son-rewhat darker than is desirable
      in the finished picture. Ingento Toning and Fix-
     ing Solution is highly recommended for toning
      this class of paper. Mix the toning solution as                 )
                      and pour                                       into     directed                                                           it               the bottle                                a tray.          on
                should                                                  solution    The prints                  be immersed                                     in                                          this                                                                                                                                                                                                                                                                    ;1":I
      face down so as to insure the even action of the                                                                                                                                 l'     solution over the whole surface of the print.
     After a moment or so, the print may be reversed
     so that the toning can be watched. Repeat this      A'
     process from time to time during toning. The
      prints .will begin  . to -change. color -immediately    upon immersion in the toning bath. At  first
     they are of a reddish brown, changing gradually
     to reddish yellow, then to brown and then to
     purple. Toning should be stopped when the de-
     sired shade has been obtained. At this point
     the prints should be transferred to a salt solu-
     tion made by dissolving one tablespoonful of
                             l8-                              -


L        --      .             '                                         I

common table salt in 16 oz. of water. The prints
       should be allowed to remain in this solution
       about 5 minutes, after which they should be wash-
      ed for one hour in running rvater or in twelve
       changes of water. They are then ready for dry-
      ing whictr can be best accornplish-ed by- using
       a 6lotte. book, such as the Ingento. Several prints
       can be toned simultaneously.
         Developing on Gaslisht Papers
         Developing Papers, such as Cyko, Velox, Argo,
         etc., are very popular with amateurs because of
      the simplicity in their operation, the excellent
        results obtained and the added advantage of be-
       ing able to print them by artificial light. These
       papers can be handled with safety eight or ten
         feet away from an ordinary gaslight. They should
       not. however. be allowed to remain uncovered
       in the direct rays of the light even at this dis-
       tance for any considerable time. The paper is
       loaded into an ordinary printing frame in the
      same manner as above described for printing-out
       papers taking care that the emulsion side of the
       paper is against the dull side of the film. The
       emulsion side of the paper can be determined by
       tendency of the paper to curl in that direction,
       or by biting a corner of the paper, the emulsioni     side tending to stick to the teeth. With the
  I      back of the frame clamped in position,  it is ex-       posed by holding it near a gas jet, lamp or in-
       candescent light. The length of the exposurert      depends upon the distance at which the frame is
       held from the light, and the density of the neg-
       ative. Exposure can also be made in subdued
        daylight, however, artificial light is  pref erred,
      as it does not vary in intensity as is the case
       with daylight and it is therefore much easier to
       judge the length of the exposure required. As
      a guide, we give the following table of compara-
        tive exposures with Cyko paper calculated for
        the various sources of light.
                              I9-                                 -

www.butkus.us
    A Comparative Table Giving Timc
                 of Exposure
               €                                                       r.q)        Lr   Lq)   rh                                ut                                tsri                                I                               B-!v5         Fl                                                        !    Fo.:                                                         ^-HOH                      h!                    ,                                               R                         q)z                          Ei,qo.r.F o  E!o9'i                                                                                                                              ob!
                       q)               o                                    H
             N          €6                         (t)                                                            q)    EtrEoac!6                                                        qr  "H8;j
Contrast  4x5 or   ? in.   20 sec.  40 sec.   I min.   14 min;
  (Blue          ller
 Label)
 Normal   4x5 or   7 in.   10 sec.  20 sec.   t0 sec.   40 sec.
 (Yellow        ller
 LabeI)
  Soft    4x5 or   7 in.   10 sec.  90 sOc.  to sec.   40 sec.
 (Red    maller
 Label)
  With this class of paper no image is seen on the
surface, until the print has been placed in  the
develooer.
 The larger the riegative, the greater the dis-
tance it should be held from the light, the usualrule being that the proper distance is equal to     l
the diagonal of the negative. The time of ex-                  Ia
posure varies with the distance the printing frame
is held from the light. By referring to the above           *Itable it will be noticed that about the same time
is required with an ordinary sixteen candle powerincandescent light as with an ordinary flat flame        1:*igas jet.   If  daylight is used, it  will be foundadvantageous to cover all the windows with      f
post office paper, with the exception of an open-
ing about one foot square. Over this opening two   +or three sheets of tissue paper should be pasted
to diffuse the light, then use a piece of black
cloth or any other opaqlle medium to cover this
opening when the white light is not desired for
printing purposes. In this case the frame should
                  -20-