Multiplying Photographs.—In Vol. viii., p. 60., you reprint a communication from Sir W. Herschel which has appeared in The Athenæum.
It describes a method of printing from glass negatives, but there being no cut renders the meaning somewhat obscure.
In the last number of the Photographic Journal (21st ult.), some mention is made of this letter. They say it proves to be one already long in use, Mr. Kilburn having practised it for four years. I am very desirous of obtaining more information about it. I want to know the length of the box or camera required; and also the focus of the lens, and the best size. Probably Mr. Kilburn or Sir W. Herschel would one of them be so kind as to say.
W. M. F.
What kind of lens should be used for taking enlarged copies of glass negatives according to Mr. Stewart's plan? and will the same lens also diminish the picture? Will not the usual camera lens act?
Ply.
[The usual compound lens is all that is required.]
Would you have the goodness to explain, in some detail, the two methods by which Mr. Stewart and Mr. Kilburn multiply photographs in a reduced or magnified size; the one by reflected light, the other by transmitted. Mr. Stewart's experiments are upon glass, Mr. Kilburn's on cameras and daguerreotypes. I have never seen any description of this latter process, or of the method of preparing the stereoscope objects: vide Athenæum, July 30, 1853.
I observe with great pleasure that the cost of apparatus is becoming less, &c.