which a ruined negative may be put are manifold. Cut down to 3 1/4
inches square and the films cleaned off, they make excellent cover
glasses for lantern slides. Another use for them in the same popular
branch of photography is the following: If, during development, you see
that your negative is spoiled through uneven density, over exposure, or
what not, expose it to the light and allow it to blacken all over. Now
with sealing wax fasten a needle to a penholder, and by means of this
little tool one can easily manufacture diagram slides from the darkened
film (white lines on black ground).
Take a spoiled negative, dissolve out all the silver with a solution of
potassium ferricyanide and hypo. Rinse, dry, rub with sandpaper, and
you will have a splendid substitute for ground glass.
Remove the silver in a similar manner from another negative, but
this time wash thoroughly. Squeegee down on this a print, and an
opaline will be your reward. From such an opaline, by cementing on a
few more glasses, a tasteful letter weight may soon be made. Another
way in which very thin negatives may be used is this: Bleach them
in bichloride of mercury, back them with black paper, and positives
will result. Old negatives also make good trimming boards, the film
preventing a rapid blunting of the knife, and they may be successfully
used as mounting tables. Clean off the films, polish with French chalk,
and squeegee your prints thereto. When dry they may be removed and will
have a fine enameled, if hardly artistic, appearance. Many other uses
for them may also be found if the amateur is at all ingenious.
Users of pyro, instead of throwing the old developer away, should keep
some of it and allow it to oxidize. A thin negative, if immersed in
this for a few minutes, will be stained a deep yellow all over, and its
printing quality will be much improved.
Old hypo baths should be saved, and, when a sufficient quantity of
silver is thought to be in solution, reduced to recover the metal.
Printing paper of any sort is another great source of waste, especially
to the inexperienced photographer. Prints are too dark or not dark
enough successfully to undergo the subsequent operations. Spoiled
material of this kind, however, is not without its uses in photography.
Those who swear by the “combined bath,” will find that scraps of
printing-out paper, or any silver paper, are necessary to start the
toning action.
Spoiled mat surface, printing-out paper, bromide paper, or platinotype
should be allowed to blacken all over. Here we have a dead-black
surface useful for many purposes. A leak in the bellows when out in
the field may be repaired temporarily by moistening a piece of mat
printing-out paper and sticking it on the leak; the gelatin will
cause it to adhere. These papers may also be used to back plates,
platinotypes, of course, requiring some adhesive mixture to make them
stick.
In every photographer’s possession there will be found a small
percentage of stained prints. Instead of throwing these away, they may
often be turned to good account in the following manner: Take a large
piece of cardboard, some mountant, and the prints. Now proceed to mount
them tastefully so that the corners of some overlap, arranging in every
case to hide the stain. If you have gone properly to work, you will
have an artistic mosaic. Now wash round with india ink, or paint a
border of leaves, and the whole thing will form a very neat “tit bit.”
Keep the stiff bits of cardboard {535} between which printing paper
is packed. They are useful in many ways—from opaque cards in the dark
slide to partitions between negatives in the storing boxes.
In reclaiming old gold solutions, all liquids containing gold,
with the exception of baths of which cyanide forms a part, must be
strongly acidulated with chlorhydric or sulphuric acid, if they are
not already acid in their nature. They are afterwards diluted with
a large proportion of ordinary water, and a solution of sulphate of
ferroprotoxide (green vitriol) is poured in in excess. It is recognized
that the filtered liquid no longer contains gold when the addition of a
new quantity of ferric sulphate does not occasion any cloudiness. Gold
precipitated in the form of a reddish or blackish powder is collected
on a filter and dried in an oven with weights equal to its own of
borax, saltpeter, and carbonate of potash. The mass is afterwards
introduced gradually into a fireproof crucible and carried to a
white-red heat in a furnace. When all the matter has been introduced, a
stronger blast is given by closing the furnace, so that all the metal
collects at the bottom of the crucible. On cooling, a gold ingot,
chemically pure, will be obtained. This mode of reduction is also
suitable for impure chloride of gold, and for the removal of gilding,
but not for solutions containing cyanides, which never give up all the
gold they contain; the best means of treating the latter consists in
evaporating them to dryness in a cast-iron boiler, and in calcining
the residue in an earthen crucible at the white red. A small quantity
of borax or saltpeter may be added for facilitating the fusion, but it
is not generally necessary. The gold separated collects at the bottom
of the crucible. It is red, if saltpeter is employed; and green, if it
is borax.
To reclaim silver place the old films, plates, paper, etc., in a
porcelain dish, so arranged that they will burn readily. To facilitate
combustion, a little kerosene or denatured alcohol poured over the
contents will be found serviceable.
Before blowing off the burnt paper, place the residue in an agateware
dish, the bottom of which is covered with a solution of saltpeter and
water. Place the whole on the fire, and heat it until the silver is
separated as a nitrate.
The solution being complete, add to the mass a little water and
hydrochloric acid, when in a short time the serviceable silver chloride
will be obtained. If the films should not give up their silver as
freely as the plates, then add a little more hydrochloric acid or work
them up separately. Silver reclaimed in this way is eminently suitable
for silver-plating all sorts of objects.
«FIXING AND CLEARING BATHS:»
«The Acid Fixing and Clearing Bath.»—Add 2 ounces of S. P. C. clarifier
(acid bisulphite of sodium) solution to 1 quart of hypo solution 1 in 5.
«Combined Alum and Hypo Bath.»—Add saturated solution of sulphite of
sodium to saturated solution of alum till the white precipitate formed
remains undissolved, and when the odor of sulphurous acid becomes
perceptible.
Mix this solution with an equal bulk of freshly prepared hypo solution
1 in 5, and filter.
This bath will remain clear.
«Clearing Solution» (Edward’s).—
Alum 1 ounce avoirdupois
Citric acid 1 ounce avoirdupois
Sulphate of iron, crystals 3 ounces avoirdupois
Water 1 imperial pint
This should be freshly mixed.
«Clearing Solution.»—
Saturated solution of alum 20 ounces
Hydrochloric acid 1 ounce
Immerse negative after fixing and washing. Wash well after removal.
«Reducer for Gelatin Dry-Plate Negatives.»—
I.—Saturated solution of ferricyanide of potassium 1 part
Hyposulphite of sodium solution (1 in 10) 10 parts
II.—Perchloride of iron 30 grains
Citric acid 60 grains
Water 1 pint
«Belitski’s Acid Ferric-Oxalate Reducer for Gelatin Plates.»—
Water 7 ounces
Potassium ferric oxalate 2 1/2 drachms
Crystallized neutral sulphite of sodium 2 drachms
Powdered oxalic acid, from 30 to 45 grains
Hyposulphite of soda 1 1/2 ounces
The solution must be made in this order, filtered, and be kept in
tightly closed bottles; and as under the influence of light the ferric
salt is reduced to {536} ferrous, the preparation must be kept in
subdued light, in non-actinic glass bottles.
«Orthochromatic Dry Plates—Erythrosine Bath (Mallman and
Scolik).»—Preliminary bath:
Water 200 cubic centimeters
Stronger ammonia 2 cubic centimeters
Soak a plate for 2 minutes.
Color bath:
Erythrosine solution (1 in 1,000) 25 cubic centimeters
Stronger ammonia (0.900) 4 cubic centimeters
Water 175 cubic centimeters
The plate should not remain longer in the bath than 1 1/4 minutes.
«PAPER-SENSITIZING PROCESSES:»
«Blueprint Paper.»—I.—The ordinary blue photographic print in which
white lines appear on a blue ground may be made on paper prepared as
follows:
A.—Potassium ferricyanide 10 drachms
Distilled water 4 ounces
B.—Iron ammonia citrate 15 drachms
Distilled water 4 ounces
Mix when wanted for use, filter, and apply to the surface of the paper.
With this mixture no developer is required. The paper after exposure is
simply washed in water to remove the unaltered iron salts. The print is
improved by immersion in dilute hydrochloric acid, after which it must
be again well washed in water.
II.—The following process, credited to Captain Abney, yields a
photographic paper giving blue lines on a white ground:
Common salt 3 ounces
Ferric chloride 8 ounces
Tartaric acid 3 1/4 ounces
Acacia 25 ounces
Water 100 ounces
Dissolve the acacia in half the water and dissolve the other
ingredients in the other half; then mix.
The liquid is applied with a brush to strongly sized and well rolled
paper in a subdued light. The coating should be as even as possible.
The paper should be dried rapidly to prevent the solution sinking into
its pores. When dry, the paper is ready for exposure.
In sunlight, 1 or 2 minutes is generally sufficient to give an image;
while in a dull light as much as an hour is necessary.
To develop the print, it is floated immediately after leaving the
printing frame upon a saturated solution of potassium ferrocyanide.
None of the developing solution should be allowed to reach the back.
The development is usually complete in less than a minute. The paper
may be lifted off the solution when the face is wetted, the development
proceeding with that which adheres to the print.
When the development is complete, the print is floated on clean water,
and after 2 or 3 minutes is placed in a bath, made as follows:
Sulphuric acid 3 ounces
Hydrochloric acid 8 ounces
Water 100 ounces
In about 10 minutes the acid will have removed all iron salts not
turned into the blue compound. It is next thoroughly washed and dried.
Blue spots may be removed by a 4 per cent solution of caustic potash.
The back of the tracing must be placed in contact with the sensitive
surface.
III.—Dissolve 3 3/4 ounces of ammonia citrate of iron in 18 ounces
of water, and put in a bottle. Then dissolve 2 5/8 ounces of red
prussiate of potash in 18 ounces of water, and put in another bottle.
When ready to prepare the paper, have the sheets piled one on top of
the other, coating but one at a time. Darken the room, and light a ruby
lamp. Now, mix thoroughly equal parts of both solutions and apply the
mixture with a sponge in long parallel sweeps, keeping the application
as even as possible. Hang the paper in the dark room to dry and keep
it dark until used. Any of the mixture left from sensitizing the paper
should be thrown away, as it deteriorates rapidly.
Often, in making blueprints by sunlight, the exposure is too long, and
when the frame is opened the white lines of the print are faint or
obscure. Usually these prints are relegated to the waste basket; but
if, after being washed as usual, they are sponged with a weak solution
of chloride of iron, their reclamation is almost certain. When the
lines reappear, the print should be thoroughly rinsed in clear water.
Often a drawing, from which prints have already been made, requires
changing. The blueprints then on hand are worthless, requiring more
time to correct {537} than it would take to make a new print. An
economical way of using the worthless prints is to cancel the drawing
already thereon, sensitize the reverse side, and use the paper again.
«How to Make Picture Postal Cards and Photographic Letter
Heads.»—I.—Well-sized paper is employed. If the sizing should be
insufficient, resizing can be done with a 10 per cent gelatin solution,
with a 2 per cent arrowroot paste, or with a 50 per cent decoction of
carrageen. This size is applied on the crude paper with a brush and
allowed to dry. The well-sized or resized papers are superior and the
picture becomes stronger on them than on insufficiently sized paper.
Coat this paper uniformly with a solution of 154 grains of ferric
oxalate in 3 1/2 fluidounces of distilled water, using a brush, and
allow to dry. Next, apply the solution of 15 1/2 grains of silver
nitrate in 3 1/2 fluidounces of water with a second brush, and dry
again. Coating and drying must be conducted with ruby light or in the
dark.
The finished paper keeps several days. Print deep so as to obtain a
strong picture and develop in the following bath:
Distilled water 3 1/2 fluidounces
Potassium oxalate (neutral) 340 grains
Oxalic acid 4 grains
After developing the well-washed prints, fix them preferably in the
following bath:
Distilled water 3 1/2 fluidounces
Sodium thiosulphate 75 grains
Gold chloride solution (1 in 100) 80 minims
Any other good bath may be employed.
II.—Starch is dissolved in water and the solution is boiled until it
forms a thin paste. Carmine powder is added, and the mixture is rapidly
and assiduously stirred until it is homogeneous throughout. It is now
poured through muslin and spread by means of a suitable pencil on the
paper to be sensitized. Let dry, then float it, prepared side down on
a solution of potassium chromate, 30 parts in 520 parts of distilled
water, being careful to prevent any of the liquid from getting on the
back or reverse side. Dry in the dark room, and preserve in darkness.
When desired for use lay the negative on the face of the paper, and
expose to the full sunlight for 5 or 6 minutes (or about an hour in
diffused light). Washing in plenty of water completes the process.
«A Simple Emulsion for Mat or Printing-Out Paper.»—One of the very best
surfaces to work upon for coloring in water color is the carbon print.
Apart from its absolute permanency as a base, the surface possesses
the right tooth for the adhering of the pigment. It is just such a
surface as this that is required upon other prints than carbon, both
for finished mat surfaces and for the purposes of coloring. The way
to obtain this surface upon almost any kind of paper, and to print
it out so that the correct depth is ascertained on sight, will be
described. Some of the crayon drawing papers can be utilized, as well
as many other plain photographic papers that may meet the desires of
the photographer. If a glossy paper is desired, the emulsion should be
coated on a baryta-coated stock.
There will be required, in the first place, 2 half-gallon stoneware
crocks with lids. The best shape to employ is a crock with the sides
running straight, with no depressed ridge at the top. One of these
crocks is for the preparation of the emulsion, the other to receive the
emulsion when filtered. An enameled iron saucepan of about 2 gallons
capacity will be required in which to stand the crock for preparing the
emulsion, and also to remelt the emulsion after it has become set. The
following is the formula for the emulsion, which must be prepared and
mixed in the order given. Failure will be impossible if these details
are scrupulously attended to.
Having procured 2 half-gallon stoneware crocks with lids, clean them
out well with hot and cold water, and place into one of these the
following:
Distilled water 10 ounces
Gelatin (Heinrich’s, hard) 4 ounces
Cut the gelatin into shreds with a clean pair of scissors. Press these
shreds beneath the water with a clean strip of glass and allow to soak
for 1 hour. Now proceed to melt the water-soaked gelatin by placing the
crock into hot water in the enameled saucepan, the water standing about
half way up on the outside of the crock. Bring the water to boiling
point, and keep the gelatin occasionally stirred until it is completely
dissolved. Then remove the crock to allow the contents to cool down to
120° F. Now prepare the following, which can be done while the gelatin
is melting: {538}
No. 1
Rochelle salts 90 grains
Distilled water 1 ounce
No. 2
Chloride of ammonia 45 grains
Distilled water 1 ounce
No. 3
Nitrate of silver, 1 ounce and 75 grains
Citric acid (crushed crystals) 95 grains
Distilled water 10 ounces
No. 4
Powdered white alum 90 grains
Distilled water (hot) 5 ounces
The latter solution may be made with boiling water. When these
solutions are prepared, pour into the hot gelatin solution No. 1,
stirring all the while with a clean glass rod. Then add No. 2. Rinse
the vessel with a little distilled water, and add to the gelatin.
Now, while stirring gradually, add No. 3, and lastly add No. 4, which
may be very hot. This will cause a decided change in the color of the
emulsion. Lastly add 2 ounces of pure alcohol (photographic). This must
be added very gradually with vigorous stirring, because if added too
quickly it will coagulate the gelatin and form insoluble lumps. The
emulsion must, of course, be mixed under a light not stronger than an
ordinary small gas-jet, or under a yellow light obtained by covering
the windows with yellow paper. The cover may now be placed upon the
crock, and the emulsion put aside for 2 or 3 days to ripen.
At the end of this time the contents of the crock, now formed into a
stiff emulsion, may be remelted in hot water by placing the crock in
the enameled saucepan over a gas stove. The emulsion may be broken
up by cutting it with a clean bone or hard-rubber paper cutter to
facilitate the melting. Stir the mixture occasionally until thoroughly
dissolved, and add the following as soon as the emulsion has reached a
temperature of about 150° F.:
Distilled water 4 ounces
Pure alcohol 1 ounce
The emulsion must now be filtered into the second crock. The filtering
is best accomplished in the following manner: Take an ordinary
plain-top kerosene lamp chimney, tie over the small end two thicknesses
of washed cheese cloth. Invert the chimney and insert a tuft of
absorbent cotton about the size of an ordinary egg. Press it carefully
down upon the cheese cloth. Fix the chimney in the ring of a retort
stand (or cut a hole about 3 inches in diameter in a wooden shelf), so
that the crock may stand conveniently beneath. In the chimney place a
strip of glass, resting upon the cotton, to prevent the cotton from
lifting. Now pour in the hot emulsion and allow the whole of it to
filter through the absorbent cotton. This accomplished, we are now
ready for coating the paper, which is best done in the following manner:
Cut the paper into strips or sheets, say 12 inches wide and the full
length of the sheet. This will be, let us suppose, 12 x 26 inches.
Attach, by means of the well-known photographic clips, a strip of wood
at each end of the paper upon the back. Three clips at each end will
be required. Having a number of sheets thus prepared, the emulsion
should be poured into a porcelain pan or tray, kept hot by standing
within another tray containing hot water. The emulsion tray being, say,
11 x 14 size, the paper now is easily coated by holding the clipped
ends in each hand, then holding the left end of the paper up, and the
right-hand end lowered so that the curve of the paper just touches the
emulsion. Then raise the right hand, at the same time lowering the left
hand at the same rate. Then lower the right hand, lifting the left.
Repeat this operation once more; then drain the excess of emulsion at
one corner of the tray, say, the left-hand corner. Just as soon as the
emulsion has drained, the coated sheet of paper may be hung up to
dry, by the hooks attached to the clips, upon a piece of copper wire
stretched from side to side of a spare closet or room that can be kept
darkened until the paper is dry. In this way coat as much paper as may
be required. When it is dry it may be rolled up tight or kept flat
under pressure until needed.
If any emulsion remains it may be kept in a cool place for 2 weeks, and
still be good for coating. Be sure to clean out all the vessels used
before the emulsion sets, otherwise this will present a difficult task,
since the emulsion sets into an almost insoluble condition.
This emulsion is so made that it does not require to be washed. If it
is washed it will become spoiled. It is easy to make and easy to use.
If it is desired that only small sheets of paper are to be coated, they
may be floated on the emulsion, but in this case the paper must be
damp, which is easily accomplished by {539} wetting a sheet of blotting
paper, then covering this with two dry sheets of blotting paper. Place
the sheets to be coated upon these, and place under pressure during the
night. Next day they will be in good condition for floating.
When the coated paper is dry it may be printed and toned just the same
as any other printing-out paper, with any toning bath, and fixed in
hyposulphite of soda as usual. Toning may be carried to a rich blue
black, or if not carried too far will remain a beautiful sepia color.
After well washing and drying, it will be observed that the surface
corresponds with that of a carbon print; if the paper has been of a
somewhat absorbent character, the surface will be entirely mat, and
will give an excellent tooth for coloring or finishing in sepia, black
and white, etc.
«How to Sensitize Photographic Printing Papers.»—I.—The older form of
paper is one in which the chemicals are held by albumen. Silver is said
to combine with this, forming an albuminate. Pictures printed on this
would be too sharp in their contrasts, and consequently “hard”; this is
avoided by introducing silver chloride.
To prepare this form of paper, beat 15 ounces of fresh egg albumen with
5 ounces of distilled water, dissolve in it 300 grains of ammonium
chloride, set aside for a time, and decant or filter. Suitable paper
is coated with this solution by floating, and then dried. The paper
is “sensitized” by floating it on a solution of silver nitrate in
distilled water, about 80 grains to the ounce, with a drop of acetic
acid. The paper is dried as before, and is then ready for printing. The
sensitizing must, of course, be done in the dark room.
The reaction between the ammonium chloride present in the albumen
coating produces a certain quantity of silver chloride, the purpose of
which is shown above. Of course, variations in the proportions of this
ingredient will give different degrees of softness to the picture.
II.—The bromide and chloride papers which are now popular consist of
the ordinary photographic paper sensitized by means of a thin coating
of bromide or chloride emulsion. In “Photographic Printing Methods,” by
the Rev. W. H. Burbank, the following method is given for bromide paper:
A.—Gelatin (soft) 42 1/2 grains
Bromide of potassium 26 grains
Distilled water 1 ounce
B.—Nitrate of silver 33 1/3 grains
Distilled water 1 ounce
Dissolve the bromide first, then add the gelatin and dissolve by
gentle heat (95° to 100° F.). Bring the silver solution to the same
temperature, and add in a small stream to the gelatin solution,
stirring vigorously, of course in non-actinic light. Keep the mixed
emulsion at a temperature of 105° F. for half an hour, or according
to the degree of sensitiveness required, previously adding 1 drop of
nitric acid to every 5 ounces of the emulsion. Allow it to set, squeeze
through working canvas, and wash 2 hours in running water. In his own
practice he manages the washing easily enough by breaking the emulsion
up into an earthen jar filled with cold water, and placed in the dark
room sink. A tall lamp chimney standing in the jar immediately under
the tap conducts fresh water to the bottom of the jar, and keeps the
finely divided emulsion in constant motion; a piece of muslin, laid
over the top of the jar to prevent any of the emulsion running out,
completes this simple, inexpensive, but efficient washing apparatus.
Next melt the emulsion and add one-tenth of the whole volume of
glycerine and alcohol; the first to prevent troublesome cockling of the
paper as it dries, the second to prevent air bubbles and hasten drying.
Then filter.
With the emulsion the paper may be coated just as it comes from the
stock dealer, plain, or, better still, given a substratum of insoluble
gelatin, made as follows:
Gelatin 1 3/5 grains
Water 1 ounce