CHAPTER VII.

DEVELOPMENT.

[Sidenote: Study of chemistry.]

Before entering on the subject of development, it is necessary to tell the student that if he does not already understand the principles of chemistry, he should lose no time in doing so, and as aids to such understanding he cannot do better than get Roscoe’s “Lessons in Elementary Chemistry,”[12] and Abney’s “Photography with Emulsions,” and master the chapters mentioned in the footnote, ignoring the rest for the time. Also let him buy Bloxham’s “Laboratory Teaching.” For a few shillings he can purchase apparatus enough to do qualitative analysis. This he will be able to do by following Mr. Bloxham’s directions, omitting, perhaps, testing with the blow-pipe. If he has the time and means, he will do well to do some quantitative analysis, working, say with water, since it is of such immense importance to the photographer. He will find a knowledge of chemistry as interesting as useful, and the power of observation and accuracy acquired by the study will be invaluable in subsequent stages of his work. We refer the student to works on chemistry by specialists, because we think it is a mistake to swell the bulk of our book by an exposition of chemical principles. We caution the student, however, who intends to take up photography as an art, to have nothing to do with plate-making. [Sidenote: Plate-making.] That manufacture can only be done satisfactorily by experts constantly employed at it, and it is as reasonable to expect a painter to prepare his own colours, and make his own canvas, as to insist upon a photographer making his own plates. Some people have tried to propagate the false idea that a picture taken on a plate of the exhibitor’s own making has a special kind of merit, but obviously this is only true when the object is an “Emulsion process competition.” In judging of the merits of a picture, no facts should be taken into consideration, save the art expressed by the picture. [Sidenote: Plates.] Still the student should know the methods by which his plates are prepared, and that his chemistry will teach him, and when he has found plates which suit him, let him keep to them. We have worked with fourteen different kinds of plates, and have found most of them good, though each requires different treatment. One piece of advice is, however, necessary, always buy your plates direct from the makers, unless you can rely upon your dealer. Some plates are, of course, much quicker than others, and this point the beginner must carefully bear in mind, making his exposures accordingly. [Sidenote: Vigilance committees.] He must not forget, however, that there are brands of plates which are “starved” of silver; these he should avoid, and it would be well if a vigilance committee were appointed in every society to test batches of plates occasionally, and report on them in the photographic journals, thus showing up the fraudulent manufacturers. Assuming, then, that the student has carefully studied the chemistry of development and has fixed on a satisfactory brand of plates, we will proceed to give him a few practical hints, but before we do so we must get rid of an obstacle in his path, and that is the wet-plate process.

Footnote 12:

Roscoe’s Chemistry:—

Lessons 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, and potassium, sodium, and ammonium in lessons 19, 22, 23; chromium and uranium in lesson 25; mercury, silver, and platinum in lessons 26, 27, and 28.

“Photography with Emulsions:”— Caps. 1, 2, 3, 5, 6, 7, 8, 9, 22, 24, and 31.

[Sidenote: Wet-plate process.]

If the student were to ask ten middle-aged photographers whether they prefer a wet plate or a dry plate negative, nine out of ten would, without doubt answer, “Oh, a wet-plate negative.” If the student is curious and asks, why? he will get a vague answer, in which the words “bloom” and “beauty” play conspicuous parts, the adjectives reminding him of an advertisement for patent balms for the skin. The fact is, not knowing the first principles of art, photographers have raised for themselves false gods, and they are still worshipping them. Let us at once and most emphatically state that wet plate negatives do not give so true an impression of nature as a gelatino-bromide plate, nor are the results so artistic. We have seen much of the best of Mrs. Cameron’s work, and she obtained from collodion and silver some of the best results ever obtained from wet plates, for she had artistic insight, yet even in her work the tonality is not so true, and the “quality” and freshness is not so fine as can be obtained from gelatino-bromide negatives. The work by this process is hard, and incapable of expressing texture correctly, while the general impression is more or less artificial. This is fortunate for us, for the slowness of the wet-plate process would seriously handicap it, even if the artistic result were better than that of dry plates. The inadequacy of collodion plates is emphasized when we look at the work of the craftsmen who used them, and whose ideal was sharpness and “bloom.” Such work will be found most unnatural and inartistic. Surely many of the false ideas current amongst photographers arose from the evolution of the art. Daguerreotypes, the first photographs, were shiny, and most of the subsequent processes followed in their wake, until one clear-sighted photographer, Blanquart-Evrard, tried to combat the evil tendencies. Considering, then, the poor artistic quality of collodion plates and their slowness in exposure, there is absolutely nothing to be said in their favour for art work. It is decided, then, that our student will work with gelatino-bromide plates.

[Sidenote: Hints to be remembered in developing.]

We venture to state briefly certain hints founded on the chemistry and practice of development, which the student must have at his fingers' ends, for let him remember that _the vital question of tone depends on development_. That exceedingly nice question of getting the tones in approximately true relation, which gives all artists so much work, gives him who uses photography as his medium no less thought, and it is on account of the _plasticity of the process of development_ that we can at once take our stand and repudiate the ignorant assertion that photography is a mechanical process. Of course there are fifty other reasons why it is not merely a mechanical process, to mention one more of which will be enough, i.e. the variety of exposures ranging between the 1/2000 of a second (as with Muybridge’s work), and a couple of hours as in taking an interior. Developing is really what modelling is to the sculptor, and as art guides the modeller’s hand, so it must the photographer’s who wishes to obtain _pictures_, and the art value of the work of both men will be proportionate to the art knowledge and insight of the workers. Now you can understand how absolutely necessary to pictorial photography is a knowledge of art. Where photographers are devoid of all art knowledge, their aim is to get “pluck,” “nice gradation,” “vim,” “snap,” “sparkle,” “brilliancy,” to use only a few of their strange and cheap terms, and, according to them all these loosely named qualities must be present equally in a sunny picture and in a grey day picture, if ever they dare to expose a plate on a grey day. It is all such talk that has brought photography down to be called a merely mechanical process, which of course it becomes in the hands of those who can and do give “pluck” and “sparkle” to every negative, regardless of effect. It never occurs to these that each picture is a problem in itself, and needs different management from beginning to end. They aim for their “sparkle” from the moment of exposure to the end of development, and obtain all the other qualities described so eloquently by their cheap adjectives, by their _unvarying_ development.

Now let the student, keeping all this in mind, carefully commit to memory these hints, for they are of vital importance.

[Sidenote: Hints.]

Placing the plate in water before using the developer is equivalent to weakening the developer.

By first immersing the plate in the pyrogallic acid solution with no restrainer or alkali, the subsequent development is slowed, and greater contrast obtained. When pyrogallic acid is added in excess, too great density and fog result. By adding pyrogallic acid, greater density and contrast are obtained.

If the high lights are getting too dense, before the detail in the shadows is well out, take the plate out of the developer and let the details develop up with the amount of solution contained in the film, and then replace it in the developer for density, if necessary.

Develop plates coated with quick emulsions to a greater density than others.

Where there is much black and white in the picture, as in photographing sculpture against black velvet, weaken the pyrogallic acid. The alkali brings up the detail, and in properly exposed pictures increases density. In excess it causes fog. The rate at which the picture is to be developed can be governed by the restrainer, which also checks detail and increases density. For long exposures the restrainer should be freely used, whilst for quick-exposure work its use should be very limited.

Too much hyposulphite in the developer tends to solarization. Although its value in the alkaline developer has been denied, we are of opinion that in certain cases it is invaluable; it accelerates development in dark shadows, rendering the reflected light in the shadows as nothing else can. Captain Abney recommends its use in the ferrous oxalate developer only, but we are well assured of its value in conjunction with the alkaline developer in all cases of very rapid exposure.

The action of the developer is of course increased by the alkali, and slowed by the oxidizing agent, but the tonality is affected unless it be well governed by the restrainer.

If a picture flashes out quickly, add the restrainer and plenty of water. If it comes up very slowly, mix a new developer containing half as much restrainer as the normal and twice as much alkali.

The quicker the action of the developer the less marked the relative tones; this is most important to remember; the pyrogallic acid should never be extremely strong, never perhaps so strong as recommended in the standard formulæ. [Sidenote: Method.] We must remember, then, that we have our three necessary factors for development, the oxidizer, the alkali, and the restrainer, all of which we can modify at will. On our minds, too, we have, or should have, a vivid impression of the picture translated into black and white; we remember what we wish to emphasize, and what to subdue, so that the resulting picture shall be true in tone and impression. We proceed then to mix our developer accordingly, remembering first that the temperature of the developing-room makes a difference, and remembering that the photographic image exists on the film to a degree proportionate to the actinic value of the light which fell upon it. Therefore, if it is a brightly-lighted landscape in sunshine, taken with a full exposure, we must get a picture in a high key, but be it remembered in such a picture the light greys will be lost in the whites, as has been already shown; on the other hand, if it is a very low-toned effect, the dull greys will be lost in the blacks. [Sidenote: Slow development.] We must never forget to develop _all plates slowly_, let this be our ever-present rule, for by developing slowly, the student has far more command over his work, and that is what every artist seeks. No haphazard work, but complete control, so that we can mould the picture according to our will. And here we must again remind the student that he can never get scientifically correct gradations from high light to deep shadow, therefore he must be prepared to get only the true impression, and as a fundamental law, let him remember to _watch over the truth of the lowest tones_.

[Sidenote: Meteorological conditions to be adhered to in developing.]

It must not be forgotten that Nature is ever varying, and that the chemicals will act differently under different conditions of temperature, mixture, electrical conditions, &c., &c., and the worker must learn to modify them accordingly; thus weaker solutions should be used in summer and on mist effects. In fact, the more one sees into photography, the more difficult does the matter become, for every picture is, from start to finish, a new problem. Artistic work is not nearly so amenable to rules as is laboratory work, where the conditions are generally more constant and better determined. Even the state of the weather at the time of exposure has great influence. The careful observer will soon see, in going over a collection of first-rate negatives, developed by the same hand and developer, that they all differ in quality, each one has physical characteristics of its own, which are the combined resultant of these protean conditions of Nature, and that such is the case is yet another proof of the individuality of a photograph _per se_, apart from any other reasons.

[Sidenote: Plates to be developed on day of exposure.]

Another very important point is the fact that the light does not act on the film proportionately to the length of exposure; the greatest action occurs at the earliest part of the exposure, as can be proved, in a rough way, by exposing a plate on different subjects for the same length of time. This fact alone at once and obviously creates a fatal objection to composite photography. It is a fact which must be constantly remembered in relation to tonality. It has been stated that an under-exposed plate can be improved by being kept (undeveloped) for several months, the idea being that the action having once begun will continue, but this is not our experience with gelatine plates, though we have observed something of the kind in working with carbon tissues. Instead of keeping his exposed plates, our advice to the student is _develop your negatives as soon as possible after exposure, never later than the day on which they are taken_, and for these reasons. First, and chiefly, because you should develop your negative whilst yet the mental impression of what you are trying for is fresh. You have, we will hope, analyzed your subject and thought it all out in black and white masses, and by developing while that analysis is still vivid to you, you stand a very much greater chance of getting a true thing. Secondly, of course, you are on the spot to take another negative if the first prove a failure. For complete success, this is the only way, and even if it entail carrying about a cumbersome dark tent, the practice will in the end bring its own reward, and it must be insisted upon as the best method of working. The astounding habit which some industrial photographers indulge in, of sending their operators all over the country, while they themselves stay at home to develop the work of those and other operators, accounts in a great measure for the numerous parodies of Nature which deck the shop-windows. This is truly mechanical work, and we are prepared to say that no one, save by mere chance, can produce perfect artistic work, _who does not develop his own plates on the spot_. [Sidenote: On over-production.] Then, again, the student of photography who wishes to produce artistic work must not hurry or over-produce. One _picture_ produced in a month would be well worth the time and trouble spent on it. We once asked an eminent landscape painter how many plates he would be content to produce in a year if he were a photographer. His answer was, “Twenty first-rate things would be good,” and _that meant working all the year round_. We recommend that saying as one worthy to be remembered. The poet Gray purchased immortality by one short poem; many historians and novelists, now forgotten, have written as many volumes as there were verses in that one poem of Gray’s, yet few would prefer the oblivion of the prolific ones to the name that Gray has won.

[Sidenote: Ferrous oxalate developer.]

But we must go back to developing, and we come now to the question of, “What developer to use?” In our opinion the ferrous oxalate developer is unsuited to artistic work. At one time we used it for negatives and positives. For negatives we do not think it gives the quality which can be obtained with the alkaline developer nor does it allow of the same control, which is, of course, a very grave fault. For positives, on the other hand, where the conditions are better known, and where absolute purity of film is required, it is very useful, but as we are not concerned with positives here, we will not go further into the matter.

[Sidenote: Chemicals.]

We must impress upon the student the necessity of always using fresh and pure chemicals, and to secure such, it is wise to procure them from a good chemist.

Re-sublimated pyrogallic acid should always be used, and re-crystallized _sulphite_ of soda, and, above all, be sure the water is pure. For all operations where chemical action results, none but pure non-aerated water should be used, preferably, boiled, distilled water, for the air and other impurities in ordinary water may be most harmful, as any one who has studied the analysis of water and air knows well.

Let the developers (the stock solutions) be mixed with boiling or distilled water, for this will aid in preserving them. The alum and hyposulphite solutions should be mixed with cold boiled distilled water, the alum bath being a saturated solution.

[Sidenote: Standard developer.]

Perhaps the simplest advice we can give as to the particular developer to be used is to take as the normal developer one mixed according to the formula sent out with the plates which the student has chosen to work with, but the student must not use it in the exact proportions given by the maker. Let the student mix up the stock solutions as told, varying the constituents as the case in hand demands. If he has carefully and thoroughly read his chemistry, and if he remembers the hints we have given him, he will have no difficulty in following out the directions.

He should, as a rule, never use more than two-thirds of the amount of pyrogallic acid recommended; let him be very careful how he uses the restrainer, and let him add the ammonia _only in small quantities_, unless the exposure has been very rapid. As a rule let him work with _weak developers_. We could easily give a dozen or even fifty formulæ for developers, but the student would be no wiser if we did, only more confused. Every photographer fancies his own particular formula, but we have no belief in any special favourites; we have worked with many, and find the results depend altogether on the quantities used and the manner of developing rather than on the constituents. Take, then, the formula recommended by your plate-maker, but use it, as we have said, with judgment. Begin with a sufficiency of pyrogallic acid (according to the subject), use little restrainer, except in over-exposure, and add the ammonia slowly, adding a few drops from time to time as required. In short, make it your rule to _use weak developers, and develop slowly_. If you think you are likely to have under-exposed, add ten to twenty drops of a one per cent. solution of hyposulphite of soda, using no restrainer. Some unscientific persons imagine that development can be reduced to a science, and that absolute quantities of each solution must be used. One might as well expect a physician always to prescribe the same doses. Each picture requires a developer of its own; that should never be forgotten. We have tried hydrokinone instead of pyrogallic acid; a given quantity of hydrokinone does the work of double that quantity of pyrogallic acid, but it has no advantages, so far as we can see, except for the development of under-exposed plates. For very rapid work we recommend the carbonate-of-potash developer, as green fog does not result. [Sidenote: Eder’s potash developer.]The formula we use is Dr. Eder’s:—

A. ℞ Pure dry mono-carbonate of potash 90 parts Water 200 ” B. Pyrogallic acid 12 ” Sulphite of soda 25 ” Citric acid 1½ ” Water 100 ”

Before using, mix forty to sixty drops of A with three ounces of water, and the same quantity of B. We generally use more water than that recommended in the formula.

Now it will be remembered that in bright sunny effects brilliancy, and therefore density, is needed; the gamut of light and shade is not so extended as in some subjects, for the shadows are bright with reflected light, but the whole must be brilliant and in a high key. In our opinion Dr. Eder’s potash developer gives this better than any other. For snow scenes, on the other hand, where there are often very black heavy shadows, we recommend, as we have done before, the developer given by the maker of the plates, used in a weak solution.

[Sidenote: Local development.]

No photographer need hope to obtain perfect results and exactly what he wishes, without resorting to local treatment; and here once more the knowledge of the artist steps in and places him at an advantage over the craftsman, but no one without sound art-knowledge should attempt this local development. On the other hand, with a thorough knowledge of the tonality of his subject, the artist can, by local development, so modify his work that he will be able to obtain wonderfully true results. Let us imagine such a subject as a dark tree in the foreground of a landscape with a bright delicate distance. No manner of development will bring these into true relation unless local treatment is resorted to. Unfortunately, directions cannot be given for this work, for each subject will of course require special treatment; the rationale of the practice, however, is founded on the general chemical principles of photography. For use in local development, then, it is always wise to keep a series of small paint-brushes at hand. All three developers may thus be used locally with great effect. During local development, the plate should constantly be re-plunged into the developer, so that the local development may not show. We strongly recommend the student _always to develop by artificial light_, for by this method he will have a more regular standard to judge of the quality of his negative than if he trusts to the varying strength of daylight.

The best way of judging of the tonality of a negative is to hold it up from time to time before the light of the developing-room; correct judgment on this matter can, however, only be obtained by long experience. The student will be told in the printed directions—supplied with many plates—that if the image does not come up in 10 or 15 seconds, the plate has been under-exposed. This is not our experience, and, as a rule, the image takes longer to show than the time named. We prefer to judge by the way the image comes up. If the highest lights come up very sharply defined and turgid, then the plate is under-exposed, but if they come up delicately, and detail begins to appear gradually over the various parts of the plate, all is well. But all this will only become familiar by experience. By constant habit the student will mentally run over the facts of the problem before him, as does a physician, and proportionately to his skill will he apply the right remedy at the right time.

[Sidenote: After treatment of plate.]

After development the plate should be well washed, and then placed in an alum bath. Alum acts as a scavenger, and clears up all the remains of the developer. Next the plate should again _be well washed_, and put in the hyposulphite bath. This bath should be constantly renewed, for as soon as it becomes well discoloured it is inadvisable to continue its use. It should not be made stronger than 1 to 5, 1 to 10 being the best proportion. Taking the plate from the fixing bath, you should wash it very thoroughly, and re-plunge it into a fresh alum bath, leaving it for a few minutes, then again wash it, and put it into a plate-washer, the water of which should be frequently changed. It can then be placed in a drying rack, and left to dry gradually in a dry room, where no dust is raised.

[Sidenote: Duplicate plates.]

It is, in our opinion, always well to expose two plates on each subject, for the operator can thus, in a second plate, correct any error he may detect in the first. This is our own invariable rule, and the practice, apart from the better results obtained, has taught us better than any other method could have done, how wonderfully the plate can be brought under the operator’s will. It is hardly necessary to say the first plate should be examined after development, by daylight, before proceeding to develop the second. Once having seen a beautiful thing in nature, the enthusiastic student will determine to get it _perfectly_, if it takes fifty plates and as many days to do it in.

[Sidenote: Study of tone.]

We strongly advise those desirous of doing artistic work to begin by studying tone, expose (always giving two exposures to each subject) on selected subjects, especially fit for the study of tone; for example, a figure in a white dress against a white background, another in a black dress against a black background, and then a white dress against a black background, and a black dress against a white background; some white flowers against a sheet of white paper; yacht-sails against the sky; faces against the sky; black velvet in bright sunshine, and on a grey day; yellow flowers (with orthochromatic plates) on a white background. In short, the student should think of all the possible harmonies and discords that can be found indoors and out of doors, and he should, before taking a plate, make a mental translation of the subject into black and white, and put on paper roughly, with a piece of charcoal, what he expects to get, by drawing rough masses in tone of the subject. He should at first think nothing whatever of composition, or the more poetical qualities of a picture; but simply study tone, and by this he will learn thoroughly exposures and development. Let him eschew all requests to take portraits, dogs, horses, parks, and what-nots; but let him always study tone. When he has mastered tone, and with it exposure and development, he knows the most difficult part of his technique and practice, let him then proceed to picture-making. In this early stage let him take anything and everything that is a study of tone, and let him take it anyhow, no posing, no arrangement, and when he knows his _métier_ thoroughly let him destroy all these early plates ruthlessly. We strongly advise him to give away no prints of early work, or he will most surely rue the day when he did so. In our opinion a year is not too much in which to work in this way, both in doors and out of doors, in studios and out, with shutter and without, before there is any attempt to take a portrait or picture of any kind.

[Sidenote: Accidents and faults.]

In working with gelatine plates various unavoidable accidents and faults will crop up, some of which can, however, be remedied. Such cases we will now go into.

[Sidenote: Under-exposure.]

Gives chalky whites and sooty blacks, _ergo_ no tonality, _ergo_ worthless. No remedy, destroy at once.

[Sidenote: Over-exposure.]

Gives thin negatives. What a thin negative is, is a matter of opinion, and must be settled by a comparison of the print with the impression of nature which it is wished to obtain. For many effects thin negatives are invaluable, and the student must not take the ordinary photographer’s opinion as to his negatives; but only that of an artist, for, as has been shown, low-toned prints are unrecognized by the ordinary craftsman, his aim and object is never to produce such things, these he designates by all sorts of names, whereas they may be, by their tonality, infinitely truer than his “sparkling” falsehoods. In short, it all depends on what the student wishes to express. Some of the best work done has been produced from negatives made purposely thin, which have at the same time been true in tone, and full of breadth. [Sidenote: Intensification.] The density of a negative can be increased by intensifying the negative; but it must not be forgotten that intensification does not, in our opinion, correct the _tonality_, this is a matter of great importance which has been overlooked. From this it will be seen that a negative that requires intensification is worthless for artistic purposes, and had better be destroyed at once. But as intensification may be required for some particular object, we must caution the student against the ordinary perchloride of mercury and ammonia intensifier. In many cases it acts well enough, in many others it acts unevenly and in patches, and in all cases it is not permanent. The best intensifier we know of is Dr. Eder’s, whose formula we give—

[Sidenote: Dr. Eder’s intensifier.]

℞ Uranium nitrate 15 grs. Potassium ferricyanide 15 grs. Water 4 ℥

Wash the plate thoroughly after fixing, so that no hyposulphite remains, and immerse in the intensifier. It works up the scale from the lower tones, which is an advantage over any other. To remove all the hyposulphite of soda it is well to treat the plate before using the intensifier, as Captain Abney directs. A drachm of a 20-vol. solution of peroxide of hydrogen should be mixed with 5 oz. of water, and the plate soaked in it for half an hour, and then washed.

[Sidenote: Fog.]

The student will find that for certain effects he may intentionally produce a slight fog over his plate, as has often been done with very good results; but if his plates are unintentionally fogged, they are ruined. Fog is due to light having had access to the plate, either during manufacture, during exposure, or during development. By developing an unexposed plate it can be proved whether it was fogged during the manufacture, as in that case the plate turns black. If the fog is caused by a leaky camera the edges of the plate, which are generally clear glass, are not fogged, for they have been hidden behind the rebate of the dark slide. Light coming through the dark slide shows itself in lines or patches, and is not general. If all these sources have been eliminated, the dark room must be suspected. This is tested by putting a plate in the slide, drawing the shutter out half way, and exposing the plate for a few minutes to the developing light. If the exposed half fogs, then the dark room is to blame.

[Sidenote: Red fog.]

We have only met with this phenomenon once, and that was in developing a uranium plate. [Sidenote: Green fog.] This is green by reflected light, and red by transmitted light. It is generally deposited at the corners of the plate and round the edge.

[Sidenote: Yellow and brown fogs.]

Are rarely met with, and are yellow and brown by _reflected_ light, whereas stains are coloured only by transmitted light. The student can easily distinguish between fogs and stains in this way. We have been very successful experimentally with Captain Abney’s method of clearing off green fog. He recommends the following solution to be used after fixing:—

℞ Ferric chloride 50 grs. Potassium bromide 30 grs. Water iv ℥

The plate should be well washed after this treatment, and developed up with the ferrous oxalate developer.

But such plates are not always saved artistically by the method, for the tonality may be thrown out, and the texture of substances is nearly always damaged.

[Sidenote: Frilling.]

Is due to the expansion of the gelatine, and will rarely occur if the plate be put in the alum bath before fixing. The gelatine can be made to contract by soaking in methylated spirits of wine.

[Sidenote: Blisters.]

Are of rare occurrence, and will dry out if the plate be carefully handled and washed in alum, as directed. They may be treated locally with methylated spirit, which causes the gelatine to contract.

[Sidenote: Dense negatives.]

The best reducer we know of is Dr. Eder’s. He recommends the use of—A., one part chloride of iron to eight parts of water. B., two parts neutral oxalate of potash to eight parts of water. A well-known authority on photographic matters, Dr. H. W. Vogel, says, “Both solutions keep a long time without deteriorating. Immediately before using, equal parts of A. and B. are mixed, forming a bright green solution, which keeps well for several days in the dark, but decomposes in the light. Of this mixture a little is added to a fresh and strong solution of ‘hypo.’ In difficult cases 1 part ‘hypo’ and 1/4 to 1/2 of iron solution are employed. The plate to be reduced is placed in this solution. The image weakens quickly and uniformly. The plate is taken out and washed just before the desired reduction is reached, because the action continues during the washing, gradually diminishing under the stream from the tap. This reducer acts on plates developed either with ‘pyro’ or ‘oxalate,’ and does not destroy the details in the shadows like cyanide. There is also less tendency to frill than with the cyanide bath.”

Reducers, like intensifiers, should not be resorted to, unless in case of a very valuable negative, for it must never be forgotten that, though the printing density is reduced, the tonality is not corrected.

[Sidenote: Yellow stains.]

Due to the developer, are easily removed by Edwards' clearing solution, which we have found most effectual—

℞ Sulphate of iron ℥ iii. Alum ℥ i. Citric acid ℥ i. Water O i.

[Sidenote: Transparent spots.]

Are due to dust in camera or slide, or to using the “hypo” bath too long. If the spots have sharply defined edges, they are due to air bubbles forming at the beginning of development.

[Sidenote: Halation.]

This is a bug-bear we have had little experience of, though we have taken many interiors. The only occasion on which we met with it was once when the plate was overexposed on a stained glass window, containing much blue in it. If a large stop be used, and the exposure kept as short as possible, our experience is that no halation need occur. If, however, the student fears it, and there is always a danger of it where any bright lights act on the film, he should, with a squegee and some glycerine, apply a piece of some dark tissue to the back of the plate; this is easily stripped off before development.

[Sidenote: Defects due to damp.]

All plates should be kept in a dry place, and whilst travelling it is as well to keep them in tinfoil. The effect of damp is to produce patches, which either do not develop at all or develop unequally.

[Sidenote: Removal of varnish.]

This is easily done by putting the plate into hot methylated spirit, and rubbing the varnish off with cotton wool.

[Sidenote: Sea air.]

It has been said that sea air affects gelatine plates, this has not been our experience.

[Sidenote: Dirty backs.]

The backs of the negatives which are generally dirty, should be cleaned by scraping, and then rubbing up with a rag moistened in hot water, or preferably, methylated spirit. The negatives should be kept in a dry place, in grooved cardboard boxes. Wooden boxes should not be used for storing either plates or negatives.

[Sidenote: Marblings.]

Are due to a dirty fixing bath; or to an uneven action of the developer arising from not rocking the plate, or to adding the alkali to the developer in the dish and not thoroughly mixing them before putting in the plate. The clearing solution removes some of these.

[Sidenote: Prolonged and patchy fixing.]

Due to the alum bath being used before “fixing” in plates from which the developer has not been thoroughly washed. It can be remedied by washing and swilling the plate in water just rendered alkaline by ammonia, and then fixing as before. We once had a plate which took several hours to fix even after this treatment.

[Sidenote: Limpet-shell markings.]

We have had these appear in a few negatives some months after development. We know of no remedy for the defect; nor do we know the cause, but believe it to be due to hyposulphite of soda left in the film.

[Sidenote: Deposit on film.]

This is sometimes met with after the imperfect washing out of hyposulphite of soda; or sometimes whilst the negative is in the fixing bath, if it has been in the alum bath previously, and not thoroughly washed. Sulphur is deposited. The remedy is obvious.

[Sidenote: Metallic patches.]

Coloured metallic-looking patches appear at times near the edges of the plate, which may, or may not, be accompanied with fog. We have often observed these patches in plates which have been kept a long time. There is no remedy if they are unaccompanied by fog, but if fog is present, the ferric-chloride solution will generally remove them.

[Sidenote: Scratches.]

On the back of the negative show as dark lines in the film.

[Sidenote: Undeveloped islands.]

Rarely, we have met with small patches which seem to have refused to develop; they are generally circular. Captain Abney says they are due to the use of chrome alum in the emulsion. There does not appear to be any remedy for this accident.

[Sidenote: Dull spots and pits.]

In one batch of plates we were greatly troubled by these faults, one of the plates being covered with pits as thickly as if it had been peppered with a pepper-box. Captain Abney says they are due to the use of gelatine which contains grease. They ruined a whole series of fine negatives for us once. These complete the enumeration of the accidents likely to occur during development.

[Sidenote: Varnishing.]

We shall now presume that the student has thoroughly dried his negatives, after having developed them. Before storing them, however, he must varnish them, to protect them from scratches, and especially from damp, for gelatine, being very hygroscopic, easily absorbs moisture. At times, when warming an apparently perfectly dry negative over a flame, preparatory to varnishing it, a slight steam can be seen to arise, due to the evaporation of the moisture in the film. This moisture in the gelatine would of course in time lead to decomposition, and ruin the image; for these reasons, then, all negatives should be varnished. Before “varnishing” each negative should be carefully brushed over with a camel’s-hair brush. [Sidenote: Dr. Carey Lea’s Varnish.] Now it is obvious that many of the varnishes used are more or less non-actinic, as Dr. Carey Lea has proved; he, therefore, recommends the following:—

℞ Bleached lac ʒ x. Picked sandarac ʒ v. Alcohol ℥ xii.

Let the lac dissolve in the alcohol, then filter, first soaking the filter paper with alcohol. Pour slowly, and if necessary at the end add 1 ℥ more of alcohol to enable the rest to pass. Next add the sandarac to the filtrate and refilter, using of course a fresh filter.

Warm the plate gently, and, holding it in the left-hand bottom corner between the thumb and finger, pour a pool of varnish on to the plate that will cover about one-third the area of the plate, then let it run to the right-hand top corner, then to the left-hand top corner, then to the thumb, and finally drain off at the right-hand bottom corner into a filter. Then place it on a drainage rack, till just set, when rewarm by the fire, otherwise it does not set hard and smooth.

[Sidenote: Roller slide.]

Since paper negatives and a roller slide were suggested by Fox Talbot, and made fit for use by Blanquart-Evrard, several ingenious persons have been trying to improve upon these early attempts. From time to time, during the last fifty years, various workers have announced old ideas as new discoveries, nor have these been confined to roller slides and paper negatives, but extended to many other photographic processes. That no one can claim any originality of discovery on this head since Talbot and Evrard is obvious; only perfected methods can be claimed. There have been many of these introduced, but none worth discussing until that offered by the Messrs. Walker and Eastman. They have perfected Talbot’s and Evrard’s work, and though they have numerous imitators, their work is _facile princeps_.

[Sidenote: Paper negatives.]

Now the student will naturally expect us to give an opinion on these paper negatives. For many photographic processes they are of course invaluable, but for artistic work our opinion is that they are not equal to the ordinary method. These remarks apply equally to the various flexible films which have lately been introduced.

For hand cameras, we should think, film negatives would be very useful, and for small studies such as they produce, would do well; but then such are not pictures. A picture must be perfect in all points, and for this reason the films will not as yet answer. They do show grain, say what people will; we have examined dozens of the very best, and that is our opinion. Besides this, they are liable to the defects common to paper, such as transparent spots, and the defects common to films, such as markings and stains, and in addition to all this there is the liability to injury of the negative after development, in the subsequent processes of oiling and stripping, if stripping films be used. The quality, too, of the picture is not equal to that of an ordinary negative. Why it is so we cannot explain. What the future of these processes may be we do not pretend to say, but for the present we feel assured that the finest quality of work is to be obtained on a glass support. For ordinary touring purposes no doubt the roller-slide and flexible films have every advantage, but with any but the art side of the question we have nothing to do. In artistic work, all hap-hazard results or accidental effects must be carefully eliminated. Lightness, printing from either side, and a good retouching basis are no considerations for the artist, he wants none of these things.

[Sidenote: Ortho-chromatic photography.]

There still remains, however, a very important point from the art point of view, as regards tonality, for as the student who has read his chemistry knows, the different parts of the spectrum act differently on the different haloids. The effect of this has been to destroy true tonality, thus a yellow flower comes out black if taken on ordinary plates. To remedy this dyes have been used which absorb the weakly acting rays, and thus has been made one of the greatest advances in photography, both scientifically and artistically. This ortho-chromatic photography has engaged the attention of experts, and Abney, Vogel, Eder, Ives, Bothamley, and Edwards are hard at work upon it now, besides many amateur scientists. We have been for some time experimenting in this direction for artistic purposes, having begun with Tailfer’s plates before any others were introduced into the English market. For the photographing of pictures Messrs. Dixon and Grey conclusively proved the superiority of the process by their exhibits at the Exhibition of the Photographic Society of Great Britain, in 1886. But the matter is different when landscapes and portraits from life have to be considered. It is with the wonderful protean aspects of nature that we have to deal when working from nature, and we feel the question is not one to be entirely settled in the laboratory. Our method is always to work out of doors, noting, as far as possible, the conditions and judging the results by the prints, and though such experiments are far from conclusive, we can at present say that the ortho-chromatic plates are nearly correct in the rendering of tonality, but not perfect, the reds overrun the other colours, and are too strongly rendered. In fact, the reds and greens are not perfectly rendered, and even if the correct values of the spectrum are rendered in a laboratory, this will not and does not give the relative tones of nature. This is the point which must be remedied. Undoubtedly ortho-chromatic photography alone will be used in the near future, but just at present it is not cut-and-dried enough for all practical purposes. The student, however, must use these plates. They are supplied by B. J. Edwards; and Dr. Vogel’s eoside of silver plates can be bought of Gotz, 19, Buckingham Street, Strand. So far the truest tonality that we have seen has been obtained on Dr. Vogel’s plates, and in addition his landscape plates require no yellow screen to be used with them, which is a tremendous advantage.

[Sidenote: Final.]

Thus it will be seen that in every operation the art-knowledge of the operator will tell. For example, let us suppose a camera set up with the lens fixed, before a beautiful landscape composed on the ground-glass screen by an artist, then let us imagine that two photographers proceed to take plates of the picture. After the very first operation of focussing, stopping and adjusting the swing-backs; a mighty gulf will separate the two pictures; the gulf widens as the exposure is made, and finally in the developed plates they are no longer the same thing. One may be a sharp, common-place fact, false in many parts, the other may be full of truth and poetry. Let a print be taken from each plate and presented to an artistically uneducated craftsman and to an artist, the craftsman will go into raptures over the sharp craftsman picture, the artist will do the same over the artistic picture, but the artist will not look for a moment at the craftsman’s ideal, and this little matter any one can prove for himself. Let the student, then, strive to earn the artist’s praise, and let him ignore the craftsman’s, and value his opinion on these matters at the same price he would value his opinions upon any other subject where taste and refinement are called into question.