The History and Practice of the Art of Photography [23]
its final polish; the circular motion is changed for a straight one across the plate, which, if intended for a portrait, should be buffed the narrow way; but if, for a landscape or view of a house, the length way of the plate.
The operation of cleaning the plate at first appears difficult and tedious, and many have been deterred from attempting this interesting art on that account; but, in reality, it is more simple in practice than in description, and with a little patience and observation, all difficulties are easily overcome. Great care must be taken to keep the buff free from all extraneous matter, and perfectly dry, and when not in use it should be wrapped up in tissue paper, or placed in a tight box.
The plate should be buffed immediately before the sensitive coating is given; particles of dust are thus effectually removed; the temperature of the plate is also increased by the friction, and the required tint more readily obtained.
SECOND OPERATION.--Applying the sensative coating.--The apparatus and chemicals required, are an
Iodine box--see fig. 14 page 53.
Bromine box--similar to the iodine box but a trifle deeper.
Dry Iodine.
Bromine, or a compound of Bromine and Chloride of Iodine, or other sensitive mixture.
Most of our best operators use the compound Bromine and Chloride of Iodine. In the early days of the Daguerreotype, Iodine alone was used in preparing the plate, and although it still plays a very important part, other preparations, called accelerating liquids, quickstuff, &c., are used, and the discovery of which has alone ensured the application of the Daguerreotype successfully to portrait taking--for when first introduced among us it took from five to ten minutes to produce a tolerable good view, while now but the fraction of a minute is required to obtain an accurate likeness.
To iodize the plate perfectly it must be placed over the iodine vapor immediately after buffing. Scatter from a sixteenth to the eighth of an ounce of dry iodine over the bottom of your coating box, and slightly cover it with cotton wool. The plate is then dropped into the frame b, fig. 12, with its silvered surface downward, and thrust under the lid h. The bright surface of the plate is soon coated with a film of iodine of a fine yellow color; it is then removed and placed over the accelerating solution. It is not absolutely necessary to perform this operation in the dark, although a bright light should be avoided. Not so the next part of the process, viz; giving the plate its extreme sensitiveness, or coating with the accelerating liquids. In this great caution should be used to prevent the slightest ray of light impringing directly on the plate, and in examining the color reflected light should always be used. A convient method of examining the plate, is to make a small hole in the partition of the closet in which you coat, and cover it with a piece of tissue paper; by quickly turning the plate so that the paper is reflected upon it the color is very distinctly shown. Most of our operators are not so particular in this respect as they should be.
ACCELERATING LIQUID.--Of these there are several kinds, which differ both in composition and action--some acting very quickly, others giving a finer tone to the picture although they are not so expeditious in there operations; or in other words, not so sensitve to the action of light. These are adopted by Daguerreotypists according to their tastes and predjudices. They are all applied in the same way as the coating of iodine. The following are the best.
Bromine water--This solution is much used in France, and, I shall therefore give its preparation, and the method of using it, in the words of M. Figeau. "Put into a bottle of pure water, a large excess of bromine; shake the mixture well, and before using it, let all the bromine be taken up. An ascertained quantity of this saturated water is then diluted in a given quantity of distilled water, which gives a solution of bromine that is always identical." M. Figeau recommends one part of the saturated
The operation of cleaning the plate at first appears difficult and tedious, and many have been deterred from attempting this interesting art on that account; but, in reality, it is more simple in practice than in description, and with a little patience and observation, all difficulties are easily overcome. Great care must be taken to keep the buff free from all extraneous matter, and perfectly dry, and when not in use it should be wrapped up in tissue paper, or placed in a tight box.
The plate should be buffed immediately before the sensitive coating is given; particles of dust are thus effectually removed; the temperature of the plate is also increased by the friction, and the required tint more readily obtained.
SECOND OPERATION.--Applying the sensative coating.--The apparatus and chemicals required, are an
Iodine box--see fig. 14 page 53.
Bromine box--similar to the iodine box but a trifle deeper.
Dry Iodine.
Bromine, or a compound of Bromine and Chloride of Iodine, or other sensitive mixture.
Most of our best operators use the compound Bromine and Chloride of Iodine. In the early days of the Daguerreotype, Iodine alone was used in preparing the plate, and although it still plays a very important part, other preparations, called accelerating liquids, quickstuff, &c., are used, and the discovery of which has alone ensured the application of the Daguerreotype successfully to portrait taking--for when first introduced among us it took from five to ten minutes to produce a tolerable good view, while now but the fraction of a minute is required to obtain an accurate likeness.
To iodize the plate perfectly it must be placed over the iodine vapor immediately after buffing. Scatter from a sixteenth to the eighth of an ounce of dry iodine over the bottom of your coating box, and slightly cover it with cotton wool. The plate is then dropped into the frame b, fig. 12, with its silvered surface downward, and thrust under the lid h. The bright surface of the plate is soon coated with a film of iodine of a fine yellow color; it is then removed and placed over the accelerating solution. It is not absolutely necessary to perform this operation in the dark, although a bright light should be avoided. Not so the next part of the process, viz; giving the plate its extreme sensitiveness, or coating with the accelerating liquids. In this great caution should be used to prevent the slightest ray of light impringing directly on the plate, and in examining the color reflected light should always be used. A convient method of examining the plate, is to make a small hole in the partition of the closet in which you coat, and cover it with a piece of tissue paper; by quickly turning the plate so that the paper is reflected upon it the color is very distinctly shown. Most of our operators are not so particular in this respect as they should be.
ACCELERATING LIQUID.--Of these there are several kinds, which differ both in composition and action--some acting very quickly, others giving a finer tone to the picture although they are not so expeditious in there operations; or in other words, not so sensitve to the action of light. These are adopted by Daguerreotypists according to their tastes and predjudices. They are all applied in the same way as the coating of iodine. The following are the best.
Bromine water--This solution is much used in France, and, I shall therefore give its preparation, and the method of using it, in the words of M. Figeau. "Put into a bottle of pure water, a large excess of bromine; shake the mixture well, and before using it, let all the bromine be taken up. An ascertained quantity of this saturated water is then diluted in a given quantity of distilled water, which gives a solution of bromine that is always identical." M. Figeau recommends one part of the saturated