Chapter VII: Introduction (5)

The theory of development is that the pyro is the developing agent and gives the strength.

The soda, or ammonia, as the case may be, gives the detail. The bromide is a restrainer, and to a certain extent will correct over-exposure. Sulphite of soda, citric acid and sulphurous acid are used to keep the pyro from oxidizing.

Therefore, when developing a plate, say a 5×7, put it in the tray and pour over it the amount of pyro necessary to develop such a plate, say two grains in four ounces of water, let the plate remain in this solution for a short time, in the meantime take of your alkaline solution the amount you would use for the [p178] same size plate, but add only a small portion to the solution covering the plate. To do this pour off the pyro solution into a graduate and add a drop or two of the alkaline solution, soda, potash or ammonia, whatever it may be, then turn the solution back on the plate and watch for the effect; if in a few minutes there is no change, then add more of the alkaline solution in the same manner, and in a short time the image will begin to appear; if it comes up too slowly, give it the remainder of the alkaline solution, and unless the plate has been under-exposed the image will come out and strengthen gradually until it has well sunken into the plate, when it may be removed and washed.

If you use the oxalate developer, proceed upon the same plan; oxalate in the place of pyro, iron in the place of alkali, but always add the iron to the oxalate, not the reverse.

Do not be persuaded that the bromide is only a restrainer; it is that and more too; it may greatly affect the quality of the negative, making it much finer in grain and clearer in the shadows.

Under-exposed plates at best make but poor negatives, and it is preferable to err, if at all, on the other side, but with the rapid plates now made exposures are very seldom too short.

When the plate has been developed it must be washed and then placed in the hypo solution to fix.

The most effective strength of hypo solution is half saturated. Make a saturated solution of hypo and dilute it with an equal bulk of water. The plate should lie in this solution until it appears perfectly clear, and about five or ten minutes longer, then it should be [p179] taken out and well washed. It should then be put in the

CLEARING SOLUTION.

Water, 1/2 gal.
Alum, 1/4 lb.
Citric acid, 2 oz.

Allow the plate to remain in this solution a few minutes and it will be found to have been greatly improved, having lost the color and cleared the shadows. This solution, besides clearing the negative, decomposes the hypo remaining in the film, and a short wash after being taken from it is sufficient.

EASTMAN'S IMPROVED NEGATIVE PAPER.

The Eastman Dry Plate and Film Co., of Rochester, N. Y., exhibited at the P. A. of A. Exhibition, at Buffalo, N. Y., in July, 1885, a very remarkable display of photographs, the negatives of which were made on gelatinized paper and called the Eastman flexible negative support. They gave a demonstration of their process at the same time, and also explained the working of their new holder for a continuous web or band of paper.

The sensitive gelatine emulsion is prepared in the same manner as for glass plates, and it is spread by means of ingenious machinery on continuous bands of paper, which bands are afterwards cut into sizes, or rolled on spools which will contain enough paper to make from 24 to 40 views or portraits, according to size.

They have invented a very neat apparatus to hold the paper when cut into sizes so that it may be inserted in the common dry-plate holder. [p180]

They have also invented and patented a roller holder which may be made to fit any camera, in which is inserted a spool of the paper, and by means of ingenious devices it may be drawn across a flat table and wound upon another roller with an apparatus to register each length of paper as an exposure is made. This apparatus is absolutely correct in operation, and the proper length of paper is infallibly transferred from the table to the roller by simply turning the roller with a key from the outside.

By this invention the viewist is given command of as many as 24 exposures, with no greater weight to carry than one double dry-plate holder when filled with glass, thus reducing his "tote" the weight of five double dry-plate holders and ten glass plates, and his resources are increased two-fold.

The exposures having been made the holder is taken to the dark room, the paper unwound from the spools, cut at the register marks and developed in the same manner as glass plates, but with the difference that several pieces may be developed at the same time in the same manner that paper prints are toned, thus securing a uniform intensity to the negatives; the fixing and washing are performed in the same manner as silver prints and as easily.

The paper negatives after being washed are dried between blotters, or in any other preferred manner, and they are then saturated with castor oil and ironed with a hot flat-iron, to make the oil more effectually permeate the fibre of the paper.

These negatives are more perfectly susceptible of being retouched and worked up than those on glass.

They are printed from the gelatine side, and when [p181] the prints are made the negatives are stored in portfolios. If after a time it is found that the oil has dried out of the film, they may be again oiled the same as at the first.

The roller holders are made for every size and style of camera box from the Detective and the Bijou pocket apparatus, up to the 20×24 mammoth size Novel Camera.

HOW TO USE THE EASTMAN-WALKER ROLL-HOLDER.

The Eastman paper films for the roll-holder are prepared in continuous bands, and are rolled up on wooden spools and neatly packed in paper boxes.

The spool may be removed from its box and placed in the holder in daylight, at the expense of the outside roll or length of paper necessary to extend from the spool to the winding-reel, so that if one were so situated as to find it necessary to change rolls in the field, the loss would be trifling--being at the utmost not more than would be required for two exposures from each spool.

The proper course, however, is to charge the holder with its spool of film in the dark room before going abroad.

In doing this it is necessary that the light in the room should be strong enough to enable the operator to see comfortably; but of such a quality as not to injure the paper, which is at least 25 per cent. more sensitive than the same emulsion would be if on glass instead of paper.

Figure 1 gives a general idea of the shape of the holder, with the slide partly drawn to show a portion of the film. Also may be seen the brass loops or clamps [p182] which hold the cover securely over the working parts, and the key at the bottom which turns the reel to which the loose end of the paper is attached.

The working parts are fastened to a light metal frame, and consist of a spool of film at the right end, and the winding reel at the left, as seen in Figure 2. Both the spool and the reel are provided with spring brakes, that prevent the uncoiling or unrolling of the paper from either the spool or reel. The milled [p183] heads of the chucks which hold the near ends of the spool and reel are provided with pawls, which, while permitting them to turn easily in the right direction, prevent the possibility of turning the other way.

When the cover, as seen in Fig. 2, is to be removed, the keyhole guard and the indicator knob are pulled out as far as they will come, the two loops on each side are turned down, the cover lifted off, leaving the working parts exposed, attached to the back of the holder by spring bolts, two at each end of the frame. Now, with the thumb and fore-finger of the right hand, press these bolts, and thus release the right end of the framework, which you may turn up, as seen in Fig. 3, which is the position for removing and replacing the roll of film.

[p184]

The proper method of doing this is more particularly shown in Fig. 4. With the left hand you hold the roll of film and draw back the spring brake; now press the end of the roller that has the saw-cut or groove across it against the chuck, as seen on the left, while the right hand unscrews the pivot or support for the other end of the roller, which is then placed in position; the pivot is inserted and screwed home.

This completes the operation of placing the roll of film in position. The frame is then turned down and secured by the two bolts, the paper band on the roll of film is torn off, and the end of the film is carried beneath the guide roller and over it and across the exposing table to the other end, which is next released and raised to a perpendicular position. The end of the film is now brought over the guide roller and attached to the winding reel, as shown in Fig. 5. [p185]

The paper is fastened to the winding reel by a metallic clamp, which is pivoted to the ends of the winding reel. Now see that the film occupies a central position across the table and over the guide rolls, and then take up the slack by means of the milled head tension screw or chuck at one end of the reel. The pawls should now be adjusted on the milled heads of the chucks, the cover replaced and fastened by raising the loops or clamps over the pins in the side of the cover, and you are ready for work.

For the purpose of indicating plainly where the first exposure will be, insert the key and screw it home then turn it slowly until you hear a sharp click, then pull out the slide and draw a pencil across the film at each end of the holder, then return the slide.

When about to make another exposure, note the position of the indicator at the right end of the holder, then turn the key slowly; the proper length will be [p186] indicated both by the sound of the sharp click within and by the position of the indicator on the outside of the holder. At every turn of the guide-roll the paper is punctured by a sharp point which occurs simultaneously with the sound of the click. For the smaller sizes, three clicks and three punctures will surely indicate that the proper length of paper has been replaced on the exposing table. For the medium sizes four clicks and punctures are required. And for the larger sizes, as many as six or eight may be necessary. The proper information is given with the holder.

When the exposures are made, and it is desired to remove the paper from the winding reel and cut it for development, proceed as before, and remove the cover from the holder; then, with a sharp knife-blade, cut the paper, as shown in Fig. 6, by drawing the blade over the paper and in the tin-lined groove in the guide-roll Then release the spring pawl at the reel end and [p187] draw the paper from the reel across the table, then cut by measurement, or by counting the punctures.

The directions for developing and preparing the films for printing accompany each package of the paper.

THE ROCHE FILM.

The year 1885 has been remarkable for the great importance of the numerous improvements in photographic processes that have been brought before the profession, and for the great impetus thereby given to the extension of the uses of the art.

The substitution of paper for glass as a vehicle for sustaining the sensitive film has long been an aspiration of the progressive photographer; and this year has witnessed the perfection of at least two paper film processes that may be said to be perfect.

The Eastman paper film has already established itself as a practical success, and now we have a new candidate for photographic favor in the Roche Film, just perfected and patented by that able experimentalist, and assigned to Messrs. Anthony & Co.

This Roche Film is remarkable for the ingenious manner by which the disagreeable necessity for oiling the paper is avoided.

This particular improvement consists in coating both sides of the paper with the same sensitized gelatine emulsion, which has the effect of preventing any trace of the fiber of the paper showing, from the fact that the light penetrating the front film has sufficient power to impress an image on the back film as well, the interstices between the fibres of the paper permitting a more energetic action of the light on the back film than through the fibre, equalizes the intensity and thus prevents [p188] the fibre showing in the negative when examined by transmitted light, or leaving any impression on prints made therefrom. The double impression has also the power of giving a more plucky or bolder character to the prints, and greatly enhancing the atmospheric effect and beauty of both portraits and landscape pictures. Also other imperfections, either in the front film or in the body of the paper, are corrected by the back coating, as neither the fibre of the paper nor any imperfection therein can have any effect on the front coating, but both the fibre and any spots, either opaque or transparent, in the paper or front film will affect the back image in the exact ratio of the opacity or transparency of the spots or imperfections.

In other words, all the imperfections of the paper and front film will be corrected by the back, rendering the double negative quite smooth and even, whatever the character of the texture of the paper may have been. This special paper offers other advantages. It will stand a protracted washing without weakening, and does not easily tear or crack from handling in the water, and when dried it will not curl, but remains flat, ready for immediate use.

Directions for development accompany each package.

ENLARGING AND DUPLICATING SMALL NEGATIVES.

Many amateurs have of late discarded their larger equipments, and for general work use the smallest sizes, such as the Detective Camera and the Bijou or Novelette, which are of the smallest sizes, such as 3-1/4×4-1/4 and 4×5.

It is contended on their part that these small outfits, which are so light and portable as to give the minimum [p189] of trouble in their use, give also (when good lenses are used) the most brilliant and perfect negatives, which are capable of being enlarged to any desirable size. Indeed, the copying and duplicating apparatus may be found in the rooms of many of the leading amateurs. And by its use many valuable negatives are duplicated, and secured against loss by breakage; others are enlarged to more useful sizes, and most beautiful transparencies are made.

THE COPYING AND DUPLICATING CAMERA.

This apparatus, as will be seen in the engraving, is a camera with an unusually long bed-rail and bellows. It has a central frame which supports a lens, and a front frame supporting a negative, so placed for duplicating or enlarging, which is done by transmitted light.

The front is fitted with a kit of frames for the various sizes of negatives, from 3-1/4×4-1/4 to 8×10, or the largest size the box is capable of producing.

For copying by reflected light the lens is removed from the central frame and adjusted or attached to the front, where the negative is seen in the cut; and the picture to be copied is attached to an upright support (which is usually a part of the copying table or stand) [p190] and exposed to the strongest diffused light available, the camera being adjusted squarely in front of it.

For duplicating or enlarging negatives the adjustment of the apparatus is as shown in the engraving. Such work being done by transmitted light. The negative to be enlarged is placed in the appropriate sized frame in front and the lens in the middle frame, which is placed nearer to the negative than to the ground glass. The conjugate focus is then found by drawing out the rear or ground glass focussing screen until the image is sharply defined on the glass. When the subject is sharply in focus, if the image is found to be too small the frame supporting the lens is pushed a little nearer the front; on the contrary, if the image is too large the lens is drawn back from the front.

For all such work the camera should be directed toward a window commanding a clear view of the sky, or if trees or buildings intervene then a sheet of tissue paper or a square of ground glass should be placed immediately in front of the camera and against the window. It will be found that Anthony's "mineral paper" is superior to either tissue paper or ground glass for this purpose, and should be used when it can be procured.

When it is desired to make a duplicate negative it is necessary first to produce a dia-positive or transparency; this is merely a copy of the negative (by transmitted light, or light passing through the negative to the lens) with its lights and shadows transposed or reversed. Great care must be taken to have this transparency in sharpest focus, and full-timed in exposure to secure line detail.

When a suitable positive has been secured it should [p191] be dried and set up in the place occupied by the negative from which it was made, and with the film side toward the lens.

The process is now repeated, but with a shorter exposure, and the resulting picture is a negative (if well done) identical with the original.

The adjustment for size is, as before mentioned, effected by moving the lens support. If it is desired to enlarge, the lens is moved nearer the subject; if to reduce, move the lens back from the front. If the duplicate negative is to be of the same size as the original, the lens is moved to the position near the centre between the front and back, which will give the image on the ground glass the same dimensions by measurements as the original.

It will be observed that as there are two plates to be used the utmost care must be taken in the adjustment of the focus and in timing the exposure in both instances, to avoid loss of definition or quality.

Duplicates and enlargements of negatives made by this process and with dry plates need be in no particular inferior to the originals, if care and skill are exercised in their production.

DUPLICATE NEGATIVES BY CONTACT.

When it is not desired either to enlarge or reduce the size of the duplicate, a more direct and simple method is to make the positive by contact printing.

Place the negative in a printing frame, and upon it lay a dry plate so that the two film surfaces are together; use a thick pad and see that the pressure is strong enough to force the two surfaces into intimate contact; now expose to a gas flame for four to six [p192] seconds and develop. This will make an admirable positive or transparency if properly done. The same process repeated, serves to make a duplicate negative from the transparency.

It is advisable to make a positive by this method from every valuable negative. This positive will serve to make duplicates from, should the original be lost or broken.

Enlarged prints from small negatives can be made by the use of Anthony's enlarging camera, and their gelatino-bromide paper by artificial light, so that when one or more or only a few large prints are required from a small negative it would perhaps be more advantageous to make them direct from the original negative by the use of this instrument than by making an enlarged negative and printing by contact. However, the latter method would be the best in cases where many prints are required.

PRINTING PROCESSES.

The amateur who has secured a fine negative of some choice bit of scenery, or has made a "hit" on any subject interesting or beautiful, will naturally desire to secure prints or impressions from it, that he may gratify his friends with a copy or supply the demand for exchanges with the members of his camera club.

The accomplishment of this desire is neither difficult nor expensive, as there are several processes by which the amateur may print for himself as many impressions as will suit his purpose. If silver prints are preferred, any photographer will produce them at small expense; or if the amateur is sufficiently posted in this branch of the art, and has the facilities, he can easily [p193] make them himself. The matter is much simplified by procuring from the nearest stock dealer or photographer, ready sensitized paper. Few amateurs, however, I imagine, would care to incur the expense of a silver-printing outfit. Those who would will find in the first part of this book full instructions in the article on silver printing.

The processes by which the amateur may most easily produce prints from his own negatives by his own skill and labor are:

The Gelatino bromide paper process.

Anthony's collodio-chloride process.

Ferro-prussiate or blue process.

Transparencies in glass or opal.

PRINTING ON ANTHONY'S GELATINO BROMIDE PAPER.

This paper is prepared with a sensitive surface, similar to the dry plates commonly used, and must be handled with the same care and subject to the same conditions of light; consequently the printing must be done by artificial light only.

The paper being cut to the sizes desired, should be kept in a light-tight box, and in a dark room. When about to print, place the negative in a printing frame in the same manner as for silver printing, lay the paper with the gelatine surface down upon the negative, place a cloth pad upon the paper, then press the frame back firmly down to secure even contact of the paper with the negative.

All this should be done in a dark room by the aid of a non-actinic light, and for this purpose Anthony's Climax Dark-Room Lantern, Patented, as shown in the following cut, [p194] would seem to fulfil every requirement. A more expensive, but very convenient instrument, however, is CARBUTT'S MULTUM IN PARVO DRY PLATE LANTERN, [p195] which has proved to be most suitable for this particular purpose.

The paper having been placed in the printing frame, the frame is set up, as seen in the [TN: following] cut, and the door in the side of the lantern opened, which permits the white light from the lamp to fall upon the surface of the negative; an exposure of from 5 to 10 seconds is all that will be necessary, even in case the negative is quite dense; a thin negative will print with less exposure, say 3 to 5 seconds, at a distance of from 12 to 15 inches from the light.

The paper when taken from the frame presents no change of surface, and must be developed in the same manner as a dry plate, to bring out the picture.

Previous to developing, lay the paper in a dish of clean water for a short time, and then transfer it to the developing tray. [p196]

The developing is done by the ferrous oxalate process. Solutions as follows:

Saturated solution oxalate potash 3 oz.
Saturated " photosulphate iron 1/2 oz.
Bromide " (12 grains bromide of
ammonium to 1 oz. water) 1/4 dram.
Saturated solution tartaric acid 2 drops.

This developer can be used several times successively until it becomes turbid. The best way is to first print and develop one print, to ascertain the proper time of exposure. Then make as many prints as are necessary, and develop them all together in a dish large enough, and with sufficient of the solution to cover them nicely. Observe carefully not to develop too far, as the resulting prints will be too dark. When the prints are developed, wash them well and fix them in a new solution of

Hyposulphite of soda 1 ounce.
Water. 8 "

The fixing will require from five to ten minutes; then wash and pass the prints through a clearing solution consisting of

Alum 2 ounces.
Water 6 "

then wash again and hang up, or place between clean blotters to dry.

It is necessary that the hands be free from any trace of silver or hypo when handling these prints while developing, or afterwards when wet, to avoid stains, etc. The same precautions as to the relative proportions of the oxalate solution and the iron are to be observed as for the development of negatives. [p197]

THE MAGIC LANTERN AND ITS USE

The Magic, or, more properly, the Projecting lantern, is an optical instrument, consisting of a case of wood or metal, enclosing a lamp or other illuminating agent, the light of which being gathered and condensed by a suitable condensing lens, and directed upon a small transparent picture, so powerfully illuminates it that its image, brilliantly lighted and greatly magnified, may be projected upon a distant screen by means of an objective--a combination of lenses in a tube--similar or identical in construction with a photographic portrait lens.

The modern projecting lantern, now a scientific instrument, bears very little if any resemblance to the earlier magic lantern, which was a rude construction, and, as its name implies, was first used by magicians, or professors of the magic arts, as a means of imposing upon the ignorance and superstition of their times. Later it became a toy for the amusement of young people. And occasionally it furnished amusement for popular assemblies, at what were called Magic lantern exhibitions, usually the projection upon a screen of greatly enlarged images of a series of comic pictures painted in brilliant colors upon glass.

The perfected instrument is now used in advanced schools and colleges for illustrating scientific lectures, and more popularly by public lecturers to illustrate by luminous projection scenes and incidents of travel, etc., without which the mere narrative would be exceedingly dry and devoid of interest.

Since dry plate photography became a popular amusement, the projecting lantern has greatly increased in public favor, and the members of the amateur [p198] photographic societies and camera clubs throughout the country are interested and engaged in the production, as slides for the lantern, of views of almost everything in animate or inanimate life.

The projecting lantern, in its highest development, is a complicated and costly instrument, the different designs and constructions of which have received, each, a long and high-sounding name, the antepenultimate of which is usually of Greek or Latin origin, such as panopticon, sciopticon, stereopticon, etc., etc., and requiring such powerful illumination as can only be furnished by the oxy-hydrogen or calcium lights or electricity.

A new instrument, however, suitable both in cost and in means of illumination for amateurs and amateur societies, has lately been introduced by Messrs. E. & H. T. Anthony & Co., which, to be in the fashion, has received the name Triplexicon.

The Triplexicon is the perfection of oil-burning lanterns; in it refined petroleum oil is burned in a burner having three wicks; the centre wick being opposite the centre of the condensing lens, and in its optical axis, entirely removes the most objectionable fault of such lanterns, the central shadow or flare.

The Triplexicon, therefore, being of its class the most perfect instrument, and requiring little if any skill to manage it, becomes the appropriate instrument for the amateur photographer whereby to exhibit in a very acceptable manner the trophies of his skill in the use of the camera and alkaline pyro.

A gentleman thoroughly familiar with all the various modifications of the magic lantern, in describing the Triplexicon says of it:

"We have seen many lanterns in our time, and in [p199] several respects this eclipses them all, especially those for use with kerosene oil only. The lamp itself is completely shielded with a well-made hood of Russia iron, and is provided with the patent triplex wick, which affords the utmost illumination obtainable with any oil light. The back and front of the hood are closed interiorly by glass plates, specially annealed to withstand extreme heat, and the rear one is again closed by perforated sheet iron, covered interiorly with a highly polished metallic reflector, back of which is inserted an eye piece of ruby glass. The latter enables one to always observe the condition of the flame and wicks, and regulate them without disturbing or discontinuing the action of the instrument. The chimney is made telescopic, to pack more compactly."

"The diffusing lens, specially constructed for the purpose, is mounted on a cylindrical slide to extend, if [p200] necessary, the focal distance, while the condensing lenses, which are of four inch diameter and can be separated for cleaning, are inserted in a corresponding slide within the wooden case.

"The case itself is quite compact, and appears very ornamental in its highly polished mahogany, with its little bronzed ventilators on either side at the bottom. The metal front is burnished and has a spiral spring adapter for the admission of the slides. A substantial wooden box contains all, and serves also as a table for the instrument while in use. Altogether this is the finest example of its kind we have yet seen; it will also serve admirably for enlargements with the gelatino-bromide paper."

LANTERN SLIDES.

The pictures prepared for projection by the magic lantern are made on glass of one size, invariably 3-1/4×4 inches, and are copies of negatives made by transmitted light and by two methods. When the negative is made by the detective, or pocket cameras and on plates 3-1/4×4-1/4, the positives or slides may be made by contact printing; that is, the prepared plate is placed in contact with the negative, film sides together or touching in a printing frame, the back pressed closely down and the plate exposed to the light of a gas or lamp flame--daylight is too strong--for from five to ten seconds, according to the density of the negative; the plate is then developed perfectly with ferrous oxalate until the picture is seen clearly on the surface; when the shadows have become sufficiently dense, or before there is any discoloration of the high lights, remove and wash and fix in hypo and alum. (See Roche's formula [p201] in article on Transparencies.) Remember that all parts of the pictures that represent the whites should be clear glass.

When the negative is larger than the slide, then the copy must be made in the Camera. (See article on transparencies.)

It is claimed by some that slides made by the collodion process are superior to those made on dry plates, but in my own personal experience I have found Anthony's transparency dry plates superior to all others and better than collodion.

To protect the film surface of the slide, thin, clear glass of a corresponding size is placed against the film surface with a paper mat (the opening of which should closely correspond with the outline of the picture) between, and the two bound together neatly with adhesive paper.

PRINTING BY ANTHONY'S COLLODIO CHLORIDE.

Collodio chloride is a collodion emulsion, consisting of plain collodion and silver chloride. It is a grayish-white substance in liquid form, and being quite sensitive to light, it must be kept in a covered bottle.

Anthony's collodio chloride is supplied in 8-ounce or larger bottles, and will keep indefinitely. The formula for its preparation is not known, but it is sold at a price that renders its preparation by individuals unprofitable.

The following formula will give a superior quality of collodio chloride to those wishing to make their own.

FORMULA FOR COLLODIO CHLORIDE.

No. 1. Nitrate silver 1 drachm.
Water 1 dram. [p202]

No. 2. Chloride of calcium 64 grains.
Alcohol 2 oz.

No. 3. Citric acid 64 grains.
Alcohol 2 oz.

To 2 oz. plain collodion add of

No. 1 30 drops.
No. 2 1 dram.
No. 3 1/2 dram.

By the use of this emulsion most beautiful pictures may be made on paper and upon porcelain, opal, stoneware, and other plain white surfaces.

When paper or any other flexible surface is to be used, it is simply coated with the emulsion. First place the paper flat upon a square of glass and pour upon it the emulsion, causing it to flow evenly over the whole surface and the excess to flow back into the bottle from the lower corner. This must be done in a subdued light, but not necessarily in a dark room or by non-actinic light, as in the case of the use of gelatine bromide paper.

When the paper is coated it should be placed in a closet or some dark place to dry, and when dried it is printed in the same manner as silver paper, by placing it in a printing frame in contact with a negative. It is printed by sunlight, and may be examined while printing, to see the progress made. The printing should be carried a shade or two beyond the color suitable for a finished print, and when done should be washed in clean water and toned with gold, and afterwards fixed in hyposulphite soda and again well washed in the same manner as for silver prints.

Flat porcelain or other enameled surfaces, before [p203] being coated with the emulsion should be albumenized in the same manner as glass plates for the collodion process.

The white of an egg to 6 ounces of water, well beaten, will be the most suitable proportion for this purpose.

For printing on porcelain or other enamel plane surfaces, specially prepared printing frames are necessary in order that the progress of the printing may be ascertained.

All articles with uneven surfaces, such as plaques, plates, saucers, of porcelain china or stoneware, that cannot be placed in printing frames, may have pictures printed on them by the aid of the Solar Camera or by Anthony's Enlarging Camera, and the lime or the magnesium light.

See Anthony's Enlarging Camera.

THE ENLARGING CAMERA

Method of making large pictures from small negatives.

[p204]

The prevalent use of the Detective Camera, and other cameras, for making pictures on small plates, has caused a demand for an apparatus whereby large pictures may be produced from such negatives.

This demand has been met by the production of Anthony's New Enlarging Camera in connection with the Gelatino bromide papers.

This enlarging box is at once simple and effective. It consists of a black wooden box containing a good kerosene lamp. The sides of the box have a number of grooves that carry a slide holding a large condensing lens, O, while another slide holds the negative, N, that is to be printed.

To the outside of one end of the box is attached a sliding bellows, and an objective, E, by which the picture is enlarged and thrown upon any white surface. In a few words, the enlarging box is a small solar camera, but using artificial light instead of the sun's rays; or it is a magic lantern so arranged that no light can come out of it except that which passes through the objective. [p205]

The use of the instrument is as simple as its construction. The lamp is lighted, and then adjusted in the box so that a shadowless circle of light is projected upon a white wall or other surface, all the light being utilized by means of the reflectors situated back of the lamp. This adjustment is effected by moving the condensing lens and the lamp nearer or farther apart. It is perhaps best to place the condenser in a groove near the objective, but sufficiently far from the end of the box to allow the slide containing the negative to be inserted. Having obtained a good circle of light, now place the negative in the slide and adjust the slide in the box so that it is between the condensing lens and the objective, and as close to former as may be. By means of the objective a good focus is now obtained, and we are ready for an enlargement.

With this apparatus and an artificial light, of course rapid printing paper is necessary. The cap is placed on the objective, and by the aid of red light a piece of the gelatino bromide paper is adjusted on the surface where the image was projected from the enlarging box. This part of the operation maybe assisted by removing the cap from the objective and placing a piece of ruby glass before it, allowing the image to fall on the paper through the ruby glass. A simple and effective way of holding the paper is to tack two common wooden laths upon a board in such a way that they will serve to hold the paper along two of its longer sides, in which case the board must be used to focus upon.

The exposure necessary will depend upon the density and character of the negative. With a medium density in a portrait negative, one minute appears sufficient, but something also depends upon the paper [p206] used, those of English manufacture being rather slow. With a little care and this little contrivance much pleasure and success are attainable in enlarging pictures from small negatives.

The use of the new "tooth" surface printing paper admits of the application of crayons to the enlargements.

By substituting the lime or the magnesium light for the kerosene lamps, pictures may be printed by the collodio chloride process upon a variety of uneven surfaces, such as plaques, plate, saucers, pots, etc., etc.

In fact, this instrument might very easily be converted into a solar camera by fixing it in a window and adjusting a mirror outside that would reflect the sun's rays into the condenser within the box.

TO ENLARGE NEGATIVES BY THE REVERSING ACTION OF LIGHT.

Having coated a plate with the common negative collodion and excited it in the usual nitrate of silver negative bath, expose it to the light for about a second at the door of the dark room, wash it and then apply to the surface as a wash a solution of

Iodide of potassium 16 grains.
Bromide of potassium 8 "
Water 1 ounce.

The plate is now ready for exposure in the enlarging camera; the lime or the magnesium light being sufficiently powerful for the purpose. On its removal from the camera the plate is washed, immersed for a brief period in the nitrate of silver bath, or otherwise treated with a solution of this salt, after which the image is developed by the ordinary developing solution [p207] for wet plates. In this way is obtained an enlarged negative from a small one without the necessity of an intermediary transparency.

PRINTING WITHOUT SALTS OF SILVER, FROM THE "SILVER SUNBEAM."

The discovery that certain of the per salts of iron when exposed to light undergo decomposition and are reduced to proto salts, is attributed to Sir John Herschell. But we are indebted to Poitevin for numerous interesting developments in this department.

For instance, the per-chloride so exposed becomes reduced to the proto-chloride; or, as Von Monckhoven more appropriately remarks, to the state of oxy-chloride. For this purpose the sesqui-chloride must be quite neutral. The ammonia tartrate, potassa tartrate and the ammonia citrate of iron are much more sensitive to light than the sesqui-chloride, and the latter salt (ammonia citrate) most of all.

The image formed by means of these salts is much fainter than that with the chloride of silver; but it can be intensified by the application of other metallic salts.

The mode of operation consists in floating the paper on the solutions in question in the dark room, in allowing them to dry, and then exposing them afterward beneath a negative, as usual with paper prepared with chloride of silver.

THE FERRO-PRUSSIATE, OR BLUE PROCESS.

The preparation of the paper by this process is very simple, and requires very few manipulations, while the results, when prints are made, are pleasing and lasting. Prints in blue are so easily made as to be [p208] extremely convenient for making proofs from negatives, and they are well adapted for mottoes, plans, drawings, manuscript, circulars, and for representations of scenery, boats, machinery, etc., etc., and for engravers' use.

Ferro-prussiate paper can be procured from E. & H. T. Anthony & Co., or can be easily made by the following formula:

Float the paper until it lies quite flat upon a solution prepared as follows:

1. Water 2 ounces fluid.
Red prussiate of potash 120 grains.

2. Water. 2 ounces.
Ammonia citrate of iron 140 grains.

When these two are dissolved, mix them together and filter into a clean bottle.

The solution should not be exposed to a strong light, and the paper must be floated on it in a very subdued light, and in the same manner as paper is floated on a silver solution. When it no longer curls, but lies flat on the solution, take it by the corners and raise it slowly from contact, and hang it up to dry in a dark place. When dry, it can be used at once, or may be kept for future use by rolling it, prepared surface in, and placing it in a tin box or other receptacle, free from light and dampness.

To make a print on this paper, place the prepared surface in contact with the negative in a printing frame and expose to sunlight.

The time of exposure will vary according to the density of the negative and the intensity of the light. The rule is to allow the light to act long enough for the portions which first turn blue to become gray, with [p209] a slight metallic luster. At this point remove the paper from the frame and place it in a dish of clean water.

It now gradually becomes a rich blue throughout, except the parts which should remain white. Change the water from time to time, until there remains no discoloration in the whites; dry, and the picture requires no further treatment.

The blue color may be totally removed at any time by placing the print in ammonia water.

This is the standard formula.

ANOTHER PROCESS FOR BLUE PRINTS.

Float the paper for a minute in a solution of

Ferridcyanide of potash 1 ounce.
Water 5 ounces.

Dry in a dark room, and then expose beneath a negative until the dark shades have assumed a deep blue color, then immerse the print in a solution of

Water 2 ounces.
Bichloride mercury 1 grain.

Wash the print, and then immerse it in a hot solution of

Oxalic acid 4 drachms.
Water 4 ounces.

Wash again, and dry.

ANOTHER PROCESS--THE CYANOTYPE.

Float the paper on a solution of the sesqui-chloride of iron. Dry and expose, afterwards wash the prints, and then immerse them in a bath of ferrid cyanide of potash. The picture will appear of a blue color in all those places where the sun has acted. [p210]

PROCESS WITH SALTS OF URANIUM.

The paper, without having undergone any preceding preparation, except that of having been excluded from the light for several days, is floated on a bath of the nitrate of uranium as follows:

Nitrate of uranium 2 drachms.
Distilled water 10 drachms.

The paper is left on the bath for four or five minutes, it is then removed, hung up and dried in the dark room. So prepared, it can be kept for a considerable time.

The exposure beneath a negative varies from one minute to several minutes in the rays of the sun, and from a quarter of an hour to an hour in diffused light. The image which is thus produced is not very distinct, but comes out in strong contrast when developed as follows:

NITRATE OF SILVER DEVELOPER.

Distilled or rain water 2 drachms.
Nitrate of silver 7 grains.
Acetic acid a mere trace.

The development is very rapid in this solution. In about half a minute it is complete. As soon as the picture appears in perfect contrast, the print is taken out and fixed by immersion in water, in which it is thoroughly washed.

CHLORIDE OF GOLD DEVELOPER.

This is a more rapid developer than the preceding. The print is fixed in like manner by water, in which it must be well washed, and afterwards dried. When dried by artificial heat, the vigor of the print is increased. [p211] Prints that have been developed by the solution of nitrate of silver may be immersed in the gold bath, which improves their tone.

The picture may be developed, also, by immersing the prints in a saturated solution of bichloride of mercury and afterwards in one of nitrate of silver. In this case, however, the times of exposure must be increased.

Pictures may be obtained, also, by floating the papers on a mixture of equal quantities of nitrate of silver and nitrate of uranium in about six times their weight of water.

When dry, they are exposed beneath a negative. In this case the image appears, as in the positive printing process, with chloride of silver, being effected by the decomposition of the nitrate of uranium, which, reacting on the nitrate of silver, decomposes this salt and reduces the silver. These prints require fixing in the ordinary bath of hyposulphite of soda, and then washing, as usual.

PROCESS FOR RED PICTURES.

Float the papers for four minutes in the preceding bath of nitrate of uranium, drain and dry. Next, expose beneath a negative for eight or ten minutes, then wash and immerse in a bath of

Ferridcyanide of potash 30 grains.
Water 3 ounces.

In a few minutes the picture will appear of a red color, which is fixed by washing thoroughly in water.

PROCESS FOR GREEN PICTURES.

Immerse the red picture, before it is dry, in a solution of [p212]

Sesqui-chloride of iron 30 grains.
Distilled water 3 ounces.

The tone will soon change to green; fix in water, wash and dry before the fire.

PROCESS FOR VIOLET PICTURES.

Float the paper for three or four minutes on a bath of:

Water 2 ounces.
Nitrate of uranium 2 drachms.
Chloride of gold 2 grains.

Afterward take them out and dry. An exposure of ten or fifteen minutes will cause the necessary reduction; the picture has a beautiful violet color consisting of metallic gold. Wash and dry.

TRANSPARENCIES ON GLASS AND OPAL.

Photography, throughout its varied range, produces no more charming or satisfying picture than the transparency, whether it is on glass for the window, or on porcelain or opal for the lamp.

The beautiful and sparkling gradation of light and shade, the variety and depth and richness of tone and color inherent in a fine example of this picture, renders it most positively "a thing of beauty and a joy forever,"

It is a picture made by a peculiarly simple and easy process, the most exalted expressions of which have always commanded the popular favor and a high price, and the working of which has, both for the amateur and the professional photographer, the highest interest and attractiveness. By no other method or process can the amateur succeed in producing pictures of [p213] equal excellence, with the same outlay of time and skill, which is a peculiarly fortunate circumstance, as the tendency among amateurs at this time is to form themselves into clubs and societies for the exchange of their most beautiful and successful efforts as picture makers. And an exchange in the form of a transparency enables the receiver to command all other styles of pictures, through the negative that may be produced from it.

The production of these pictures has assumed such importance already as to have called forth a special dry plate for making transparencies, to say nothing of the other special goods for the same line, such as metal frames, ground, engraved and etched glass for mounting, the beautiful borders of which greatly enhance the beauty and elegance of the finished picture.

Transparencies are adaptable for the exhibition of every kind of picture that can be copied; paintings, engravings, portraits, landscapes, all become equally acceptable when skilfully finished and properly displayed.

By this process, also, the amateur is enabled to provide himself with slides for his magic lantern and to have the satisfaction of exhibiting to his friends the trophies of his own skill in the use of the camera and the developing solution.

The amateur, in order to succeed in producing high class work, should possess himself of one of Anthony's duplicating and copying cameras, so that he may be enabled to avail himself of both methods of work; that is to say, by the camera and by contact printing, as by the latter method he is restricted to the range and size of his negatives, while by aid of the camera he is enabled to copy all kinds of pictures to acceptable sizes, [p214] and he can make his transparencies of equal size with his negative, or vary the size to suit the requirements of the case.

The use of the duplicating and copying camera is fully detailed in the article on Duplicating Negatives. By its use the amateur is enabled to work by the wet collodion process, which has many advantages, or by the dry plate process, using Anthony's transparency plates or the gelatino albumen plates made in Philadelphia. If he confines himself to contact printing, he is restricted to the use of dry plates only.

The outfit of goods for making and finishing transparencies consists of:

Transparency frames, common and patented, made with rings for
hanging horizontally or vertically.

Ground glasses, with borders.

Etched glasses, with borders.

Anthony's transparency plates.

Gelatino albumen plates.

Porcelain and opal plates for lamp shades, etc., etc.

FORMULA FOR DEVELOPING DRY PLATE TRANSPARENCIES.

When making transparencies by contact use artificial light, either gas or a common lamp. A deep printing frame is the most suitable, having a piece of thin plate glass in it to support the negative. Lay the negative down with the film side up, place upon it the dry plate, put in the back and press firmly down with the springs; expose to gas light from six to ten seconds at a distance of twelve to fourteen inches; expose longer to lamp light, say from ten to twenty seconds, or the duration of time that may be considered sufficient, judging from the density of the negative in use. [p215]

The time of exposure and the strength of the developers are the most important factors in determining the quality and tone of the resulting transparency. Giving a short exposure and using a strong developer will ensure a vigorous picture with a rich velvety black tone. A long exposure, necessitating a weak developer, will produce fine gradation of light and shade, clear shadows and a warm brown tone.

When making transparencies for the window, cut a mask, with an opening, allowing for the border or margin on the ground glass it is intended to use. A suitable paper for this purpose is of deep orange color and moderately heavy; place the mask between the negative and the dry plate to be acted on, and it will protect the margin from the action of light, leaving it clear glass, and so exhibiting to better advantage the ornamented border of the ground or etched glass, which is placed against and covers and protects the film of the dry plate. When making lantern slides the mask is not necessary.

FERROUS OXALATE DEVELOPER FOR TRANSPARENCIES.

No. 1.

Sulphate of iron (Anthony's) 2 ounces.
Distilled or ice water 32 "
Sulphuric acid 8 drops.

No. 2.

Neutral oxalate of potassium 8 ounces.
Warm distilled water 32 "
Citric acid (or tartaric) 60 grains.
Bromide of potassium 180 "

When about to use, mix equal parts of Nos. 1 and 2, always pouring No. 1 into No. 2. [p216]

The exposure having been made in the camera or in the printing frame, place the plate in the developing tray and pour upon it sufficient of the developing solution, mixed as directed, to cover the plate at once, and keep it in motion from time to time. Develop until detail in the high lights is plainly visible. When this is the case remove the plate, wash well and fix in hypo-solution.

Water 20 ounces.
Hyposulphite of soda 6 ounces.

When the plate is quite cleared, of which it is better to make sure by leaving the plate in the fixing solution for fully five minutes after it first appears clear, remove it and wash again very thoroughly, and then immerse it in the clearing solution.

Water 20 ounces.
Sulphuric acid 1/2 "
Alum 2 "