A sheet of any smooth-surfaced glass (plate is best) is cleaned by any of the usual photographic methods; now rub over the plate a solution of alcohol containing about 5 drops nitric acid to the oz.; rub oyer the glass, and polish with a dry piece of Canton flannel; finally dust a little soapstone or French chalk from a small muslin-covered box containing the chalk; brush it off lightly with a clean piece of Canton flannel; be careful not to rub hard, as in that case the chalk would deaden the polish of the glass plate. This done, the glass is coated with plain collodion, 5 gr. cotton to the oz. of equal parts alcohol and ether. The plate is allowed to dry, and can be kept in this state any reasonable length of time. When dry, lay the plate upon some level place, and cover with a solution of plain gelatine about the consistency of cream, at a temperature of 90°-100° F. (32°-38° C); allow the plate to lie flat until the gelatine sets, which will depend on the temperature of the room.
When dry, stand the plate (or plates) up to dry, and store them away; in this state they will keep indefinitely, and it is well to keep a stock on hand in this condition, as pictures can be mounted in a few moments.
To mount the picture, lay one or more plates upon some level place over the sink, so that the water to be used will have free escape to the waste pipe. Cover the plates fully with water, allowing as much to remain on the surface as possible; lift the pictures from the water they have been washed in, and lay them face down upon the prepared surface of the plate, filling it with as many prints as it will hold, arranging them according to their sizes; pay no attention whatever to the bubbles. Have a piece of thin rubber cloth and a squeegee; lay the rubber cloth over the plates, and with the squeegee press the pictures into contact with the glass, at the same time take out all air-bells by passing it back and forth over the plate. This done, run around the edge of the plate with a knife to cut off the gelatine and collodion, 1/2 in.; this is to allow the paper that is mounted on the back of the picture to adhere to the glass, which will thus bind the whole thing down until liberated by being cut inside this safety edge, otherwise the pictures would be apt to leave the glass before they are thoroughly dry, and thereby lose the brilliancy they would have if properly dried.
After the pictures have got surface dry, give them a coat of thin gelatine, and cover them with a sheet of Manilla paper or any common paper, same size as the plate; now mount them with cardboard, known as printers' cardboard, because it is cheap and answers every purpose; finally cover the whole with an enamel sheet of paper of any tint desired, thus having an enamelled mount, when the picture is finished, as well as an enamelled photograph. After they are thoroughly dry, cut inside the safety edge, when the prints will come off with all the beautiful finish possible. The prints may now be stamped out with a round or square cornered die, or cut with a knife any desired shape; the edges may be bevelled and bronzed with a little gum-arabic and bronze applied with a camel-hair brush. (T. Inglis.)
The art of toning is one which the amateur is apt to give too little attention to. Excellence in all the manipulations connected with the production of a negative, even including the making of the plates, and, indeed, excellence in every operation in the production of the finished picture up to that of toning, is common enough with amateurs. Excellence in toning is not so common. "Nothing is easier than to tone, nothing more difficult than to tone well," had been said; and there certainly is much truth in the saying. By excellence in toning we mean not only the ability to get a good colour with pure whites and transparent shadows, but also the power of getting any tone we require, of course confining our requirements to the possibilities of the matter. The variation produced by varying the toning bath and manner of toning is not confined to the colour obtained only, but shows itself in the general quality of the print. You may have 2 prints taken from the same negative, and printed on portions of the same sheet of paper. The colour of the tone is not very different: it would be described as a warmish brown in each case. The difference in the general appearance is, however, great.
The one is a clear, brilliant, and pleasing picture; the other, though it would scarcely be placed in the category of" mealy prints," is a flat, dirty, uninteresting-looking object. Now these 2 prints were toned in the same bath. They show how much depends on the small details of the process merely.
Beginning at the beginning, and taking in succession the various small matters which we have found worthy of attention if we desire to get a pleasing colour in our prints, we may take first of all the quality of the negative. As is generally known, the influence of this on the tone of the finished print is very great, but wherein this influence exists is apparently not quite fully understood. It is commonly said that a negative showing strong contrast will give a print which may be toned to a rich colour; but something more than this appears to be required. A negative with a contrast ever so great, if underexposed, will not give a print readily toned to a pleasing colour. It is difficult to see why it should be so, but it is evident that the gradation of density of the negative is a great factor in the colour of silver prints obtainable from it. We will get, as a rule, a better tone from a negative which might be described as "somewhat delicate but full of detail" than from the densest possible negative which is even a little under-exposed.
We do not intend at present to enter into the question of the manufacture or sensitising of the paper, because, as a rule, amateurs use ready-sensitised paper. We, therefore, pass on to the actual printing. It is an opinion commonly held that the longer, within limits, a print remains exposed in the frame - that is to say, the poorer the light - at the time of printing, the better will be the tone. It is certainly the case that prints done in very brilliant sunshine, and, therefore, in a very short space of time, do not, as a rule, tone as well as those which have taken longer to print; but we have not found the difference to be very great.
The manner of keeping the paper both before and after printing is a matter of importance, as we all know ready-sensitised paper turns brown from being kept. It may, however, turn in two totally different ways. It sometimes turns of the same colour that it would were it slightly exposed to light. This appears to be the effect of the action of pure air and damp, and does no harm so far as the colour obtainable by toning is concerned. There is, however, a very different discoloration which results from exposure to the smoky, impure air of London, and probably comes about from the action of sulphur in some form. It is distinguished by a metallic lustre; the effect of this is disastrous on the tone of the print. Nothing but the most sickly colour is possible from paper which has turned its colour in the manner described. From this we gather the importance of keeping ready-sensitised paper in a place where the air is as pure as possible.
It is probable that the stage at which the most can be done to make or mar the tone of a print is that of the washing which is performed previous to the toning. If, for example, the prints be placed in the water in masses, and be allowed to adhere one to another for any length of time - or, in fact, if they be allowed to remain for any length of time in water which contains a considerable quantity of the free silver nitrate which washes out of them - ruination of the tone will be the result.
It appears to be of importance to get the first silver which is washed from the prints away from them as quickly as possible, and for this reason they should be placed first in a large vessel, and should be removed from this first washing vessel to a second after a very short immersion. The next point of importance is the extent to which the washing should be carried. Here let us say that we are in favour of eliminating all, or very nearly all, the free silver nitrate by very thorough washing, followed by the application of a solution of common salt to convert what silver nitrate is left into chloride.
There appear to us to be various objections to the presence of free silver nitrate in the prints at the time of toning. For one thing, it is a very uncertain factor in the process. We never can tell how much we have washed away and how much we 'have left, and consequently there is uncertainty introduced in the result. When we wash out all the silver nitrate the uncertainty ceases; and not only that, we find that if, as certainly is the case, the toning takes much longer, or requires a much stronger solution of gold, the result is infinitely better than that got when silver nitrate is present. A further great advantage lies in the fact that prints toned without the presence of silver nitrate do not change their colour in the fixing bath; those toned in its presence do. We have, therefore, if we have thoroughly washed our prints, merely to wait for the colour we require, and then to remove the print from the toning bath. It certainly is the fact that with most ready-sensitised paper it is impossible to get a very good purple tone.
We can, however, get a very warm brown.
Concerning the use of the salt solution, it would appear from mere theoretical reasoning that there can be no need for any washing at all before using it. It is difficult to see why it should be objectionable to get rid of the whole of the silver nitrate by converting it into chloride, but the fact remains the same that we do not get a good result if we place the prints direct from the printing frame into the salt water. It is also a fact that if the salt solution be beyond a certain strength, the prints refuse to tone at all. Considering these two facts, it becomes merely a matter of experiment to determine how to use the salt. We have proceeded as follows with good results.
We wash the prints till the greater part of the muddiness of the washing water has disappeared: this means 3 or 4 changes of water. We then dip for 10 minutes in water which contains 1/2 oz. common salt to each gallon. After that we wash in other 3 changes of water, and proceed to tone. The only-difference in the manipulation in toning the 2 prints mentioned above was that the first was allowed to soak for some time in its first washing water, and was then but imperfectly washed. The second was at first rinsed briskly in running water, and was afterwards treated with the salt solution as described. It took 5-6 times as long to tone as the first. For the sake of completeness, we give the formula we were using, although we believe the difference in result produced by different toning formulae is vastly less than the difference which may be brought about by varying mere details of manipulation : -
Gold chloride .. .. .. 1 gr.
Borax .. .. .. .. 60 gr.
Water .. ••..... 12 oz.