American Hand Book of the Daguerreotype [42]
dust to come in contact with the surface of the plate. The plate is now to be attached to the pole of the battery.
After remaining a short time, it assumes a blue color; take it out, rinse freely with pure water, then dry with a spirit lamp, and it is ready for buffing. Buff and coat in the usual manner. Some operators are in the practice of immersing the plate in the solution and buffing twice. This additional silvering is no improvement wherever there has been a proper first coating.
Sometimes the operator is troubled with streaks or scum on the plate. This may arise from three causes, all of which experience must teach the experimenter to avoid; first, too great an excess of cyanide in the solution; second, a lack of silver; third, the current too strong. Another annoyance arises from the solution being dirty and the dirt collecting on the surface. When this is the case, the dirt is sure to come in contact with the surface of the plate as it is plunged into the solution, and the result is a scum that it is difficult to dispose of. This can be prevented only by frequent filtering. One thing should always be borne in mind in electrotyping Daguerreotype plates--that in order to secure a perfectly coated surface, the plate should be perfectly cleaned. In this point, many who have tried the electrotype process have failed, attributing their ill success to other than the proper cause.
DAGUERREOTYPES WITHOUT MERCURY.
The following process possesses some interest, and is worthy a trial from operators. M. Natterer, of Vienna, discovered a process for obtaining proofs on iodized plates with the chloride of sulphur, without the use of mercury. A plate of silver is iodized in the usual manner, and then placed on the top of a vessel six or eight inches high, having at the bottom, in a small cup, a few drops of chloride of sulphur; it should remain exposed to the action of the vapor until the sombre yellow color is changed to a red, after which it is brought to a focus m the camera, where it is exposed to the light in the camera, for about the time necessary to produce an ordinary daguerreotype. The plate is then taken out and examined in the camera by the light of a candle. It often occurs that no trace of the image is as yet perceptible, but if the plate is heated by placing over a spirit lamp the unprepared side, or if left for some time in the dark, or, lastly, if exposed only a few seconds to a weak, dimmed light, the positive picture then appears with all its shades. Of these three modes of bringing out the image, the second is superior to the others.
MANAGEMENT OF CHEMICALS.
It is necessary, first of all, to know that you have a chemical which is capable of producing good results when in skillful hands. For this reason it is best to prepare your own quick, after some formula which is known to be good. Those quick-stuffs which contain chloride of iodine are noted for their depth of tone while they probably operate with less uniformity than those which are destitute of it. For operating under ordinary circumstances, especially with an inferior light, probably no accelerator is more quick and sure than Wolcott's. It also produces a very fine, white pleasing picture, though lacking that depth of impression so much to be desired. The dry quick operates with surety, and its use is simple and easy, producing an impression much like Wolcott's. For those having a good and permanent light, however, we would recommend a chemical giving more body to the impression.
There is a class of accelerators called sensitives, claiming to work in from three to ten seconds, which, however, will be found very little, if any, more sensitive than this. We frequently work it with the ordinary coating in twelve and fifteen seconds. The manner in which the sensitives are worked is by coating very light. In this way, a flat, shallow picture is obtained in a few seconds; and the same can be done with any of the more volatile quicks.
It is a fact not generally known, that a plate coated in a light chemical room is more
After remaining a short time, it assumes a blue color; take it out, rinse freely with pure water, then dry with a spirit lamp, and it is ready for buffing. Buff and coat in the usual manner. Some operators are in the practice of immersing the plate in the solution and buffing twice. This additional silvering is no improvement wherever there has been a proper first coating.
Sometimes the operator is troubled with streaks or scum on the plate. This may arise from three causes, all of which experience must teach the experimenter to avoid; first, too great an excess of cyanide in the solution; second, a lack of silver; third, the current too strong. Another annoyance arises from the solution being dirty and the dirt collecting on the surface. When this is the case, the dirt is sure to come in contact with the surface of the plate as it is plunged into the solution, and the result is a scum that it is difficult to dispose of. This can be prevented only by frequent filtering. One thing should always be borne in mind in electrotyping Daguerreotype plates--that in order to secure a perfectly coated surface, the plate should be perfectly cleaned. In this point, many who have tried the electrotype process have failed, attributing their ill success to other than the proper cause.
DAGUERREOTYPES WITHOUT MERCURY.
The following process possesses some interest, and is worthy a trial from operators. M. Natterer, of Vienna, discovered a process for obtaining proofs on iodized plates with the chloride of sulphur, without the use of mercury. A plate of silver is iodized in the usual manner, and then placed on the top of a vessel six or eight inches high, having at the bottom, in a small cup, a few drops of chloride of sulphur; it should remain exposed to the action of the vapor until the sombre yellow color is changed to a red, after which it is brought to a focus m the camera, where it is exposed to the light in the camera, for about the time necessary to produce an ordinary daguerreotype. The plate is then taken out and examined in the camera by the light of a candle. It often occurs that no trace of the image is as yet perceptible, but if the plate is heated by placing over a spirit lamp the unprepared side, or if left for some time in the dark, or, lastly, if exposed only a few seconds to a weak, dimmed light, the positive picture then appears with all its shades. Of these three modes of bringing out the image, the second is superior to the others.
MANAGEMENT OF CHEMICALS.
It is necessary, first of all, to know that you have a chemical which is capable of producing good results when in skillful hands. For this reason it is best to prepare your own quick, after some formula which is known to be good. Those quick-stuffs which contain chloride of iodine are noted for their depth of tone while they probably operate with less uniformity than those which are destitute of it. For operating under ordinary circumstances, especially with an inferior light, probably no accelerator is more quick and sure than Wolcott's. It also produces a very fine, white pleasing picture, though lacking that depth of impression so much to be desired. The dry quick operates with surety, and its use is simple and easy, producing an impression much like Wolcott's. For those having a good and permanent light, however, we would recommend a chemical giving more body to the impression.
There is a class of accelerators called sensitives, claiming to work in from three to ten seconds, which, however, will be found very little, if any, more sensitive than this. We frequently work it with the ordinary coating in twelve and fifteen seconds. The manner in which the sensitives are worked is by coating very light. In this way, a flat, shallow picture is obtained in a few seconds; and the same can be done with any of the more volatile quicks.
It is a fact not generally known, that a plate coated in a light chemical room is more