American Hand Book of the Daguerreotype [34]
Now this is a great mistake, and we will here state that in all cases where dampness appears upon a properly prepared Daguerreotype plate, it is the result of a different temperature of the metal from the air which surrounds it. Mr. Senter, of Auburn, was the first of our operators who used a solution of iodine for coating the plate, and we several years since saw his results, which would rival the production of any other operator. A concentrated solution of iodine is prepared by putting into a common bottle two thimblesful of hyposulphite of soda and a rather larger quantity of iodine, so that there may be more than sufficient. Add to it about 40 ounces of common water (heated to 60 or 70 degrees), by little and little, moving, the bottle to warm it, for fear of breaking. After shaking it a short time, the water is rapidly and strongly colored. The solution should be poured into a bottle with a ground stopper, and when cool used for iodizing.
A solution of sufficient strength can be made by moistening or just covering the iodine with water.
Chloride of Iodine as an Accelerator.--This is probably one of the best accelerators that can be used for coating the plate for taking views; it works too slow, however, to meet the wants of the operating room, yet its use was formerly, for a long time, adhered to by some of our best professors. In producing views with this, we are successful in obtaining well-developed impressions, with a depth of tone and richness of appearance not to be met with in the productions of any other substances. I give its use as furnished me by an old and experienced operator, and published in Humphrey's Journal, vol. i. p. 180:
"As the process of using chloride of iodine may be of interest to some of our subscribers, I take pleasure in giving the following manipulation. To one ounce of chloride of iodine add two ounces of water; place this mixture in a coating-box, the same as quick stuff; coat the plate with dry iodine to a light yellow, or lemon color; then bring the coating to a deep pink over the chloride. The plate must be recoated over the dry iodine."
This combination has been very successfully used in one of our most extensive establishments in this city, and the superiority of the pictures produced by it was considered as an equivalent for the additional time required to bring out the impressions.
Chlorine as an Accelerator.--I shall here refer to but a single experiment in which I employed chlorine gas for coating the plate. I was provided with a retort, the neck of which was fitted to the jar of my coating-box, through a hole drilled for its reception. This was fitted perfectly tight in my coating-box. I placed some pure undiluted bromine water and the agents necessary for producing chlorine gas (in small quantity) in the retort. The result was that my first experiment produced an impression completely solarized in all its parts by an exposure of four seconds of time, which would have required an exposure of twenty seconds to produce a perfectly developed impression by the usual process.
Another trial immediately produced one of the finest toned impressions I ever saw, perfectly developed in one second of time.
My next two or three experiments proved total failures. I was unable to produce even a sign of an impression. By accident my retort was broken, and not being in a locality convenient to obtain another, my experiments were necessarily suspended.
My attention was not called to this subject again for several years, when I noticed an account of some similar experiments by F. A. P. Barnard and Dr. W. H. Harrington, the latter of whom is now of the firm of Dobyns & Harrington, of New Orleans.
From reading this article, I found my own difficulties explained. Too much of the chlorine gas was present in my coating jar. I would like to see some of our enterprising operators investigate this combination.
It is a singular fact, that the vapors of bromine and chlorine combining upon the iodide of silver, produce a more sensitive coating than when the two are combined
A solution of sufficient strength can be made by moistening or just covering the iodine with water.
Chloride of Iodine as an Accelerator.--This is probably one of the best accelerators that can be used for coating the plate for taking views; it works too slow, however, to meet the wants of the operating room, yet its use was formerly, for a long time, adhered to by some of our best professors. In producing views with this, we are successful in obtaining well-developed impressions, with a depth of tone and richness of appearance not to be met with in the productions of any other substances. I give its use as furnished me by an old and experienced operator, and published in Humphrey's Journal, vol. i. p. 180:
"As the process of using chloride of iodine may be of interest to some of our subscribers, I take pleasure in giving the following manipulation. To one ounce of chloride of iodine add two ounces of water; place this mixture in a coating-box, the same as quick stuff; coat the plate with dry iodine to a light yellow, or lemon color; then bring the coating to a deep pink over the chloride. The plate must be recoated over the dry iodine."
This combination has been very successfully used in one of our most extensive establishments in this city, and the superiority of the pictures produced by it was considered as an equivalent for the additional time required to bring out the impressions.
Chlorine as an Accelerator.--I shall here refer to but a single experiment in which I employed chlorine gas for coating the plate. I was provided with a retort, the neck of which was fitted to the jar of my coating-box, through a hole drilled for its reception. This was fitted perfectly tight in my coating-box. I placed some pure undiluted bromine water and the agents necessary for producing chlorine gas (in small quantity) in the retort. The result was that my first experiment produced an impression completely solarized in all its parts by an exposure of four seconds of time, which would have required an exposure of twenty seconds to produce a perfectly developed impression by the usual process.
Another trial immediately produced one of the finest toned impressions I ever saw, perfectly developed in one second of time.
My next two or three experiments proved total failures. I was unable to produce even a sign of an impression. By accident my retort was broken, and not being in a locality convenient to obtain another, my experiments were necessarily suspended.
My attention was not called to this subject again for several years, when I noticed an account of some similar experiments by F. A. P. Barnard and Dr. W. H. Harrington, the latter of whom is now of the firm of Dobyns & Harrington, of New Orleans.
From reading this article, I found my own difficulties explained. Too much of the chlorine gas was present in my coating jar. I would like to see some of our enterprising operators investigate this combination.
It is a singular fact, that the vapors of bromine and chlorine combining upon the iodide of silver, produce a more sensitive coating than when the two are combined