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THE PHOTOGRAPHIC NEWS. Vol. XI. No. 483.—Decemler 6, 1867. CONTENTS. A Simple and Efficient Mode of Producing Enlargements 581 Echoes of the Month. By an Old Photographer 582 Fireside Musings. By W. T. Bovey 584 The Magic Lantern and Photography. By James Martin 585 A Lesson Learned in Paris. By a London Photographer 586 On Developing and Printing. By Carl 587 The Chassis-Cuvette, or Sensitizing Frame 587 Stereographs, and How to Make Them. By J. Q. A. Tresize ... 588 PAGE Suggestions for the Best Effect in Stereographs The Negative Photographic Target. By Simon Kaes Correspondence-M. Salomon’s Pictures—M. Adam-Salomon’s Portraits Talk in the Studio 589 590 590 591 591 To Correspondents. 592 A SIMPLE AND EFFICIENT MODE OF PRODUOING ENLARGEMENTS. The method of enlargement to which we are about to call the attention of our readers is not new in itself, but it is so little known, and so much less understood and appreciated by the majority of photographers, that it will, we feel sure, be a practical novelty to many. By the method in question, enlargements may be produced to the extent of four or five diameters—that is, heads of one inch long may be amplified to four or five inches long — with a greater degree ol delicacy, half-tone, and sharpness than by any other method we know. The prints are produced more quickly than by any process we know, and they possess more promise of permanency than the results of any other method of silver printing. No solar camera o r other expensive apparatus is required ; and the operations are so simple that every photographer who can take a negative can, with but little ingenuity, and a reasonable amount of practice and perseverance, produce enlargements by the method we are about to describe. We have said the process is not new : indeed, we made some experiments in working it out half a dozen years ago, but it is only recently that we have had fully impressed upon our own mind the importance of the process. Some little time ago an eminent portraitist called our attention to some enlargements from card size to twelve by ten inches, and asked our opinion of them, and also if we saw anything peculiar in them. Our reply was, that they were singularly soft, delicate, and sharp for enlargements, but that they appeared to be prints on albuminized paper, we presumed from enlarged negatives. He then informed us that these were images on wet collodion, produced in the camera like transparencies, and the film then transferred to plain paper. We had shortly before heard that Mr. Ernest Edwards was producing beautiful results by a similar process, and some points in connection with which he had patented. Very soon after we had a visit from another very able photo grapher to show us an important novelty in enlagement, which he had during the last twelve months been working out, and his pictures, which were very beautiful indeed, turned out to be by a similar method. Wo mention these facts to illustrate another of the curious coincidences which not un- frequently occur in the history of photography. Three gentlemen, all eminent in the profession, had been working out, each independently of the other, and without any knowledge of the operations of the other, something he thought new, and which was undoubtedly beautiful. The process in general features is that originally intro duced by Dr. Moitessicr, and more recently extensively applied by M. Disderi, under the name of the email process, in printing card portraits. Its especial advantages in simplicity will bo readily understood, especially by por traitists, who wish themselves occasionally to produce en largements without the trouble and expense of a solar camera. But it has one notable and special merit in the fact that within moderate dimensions there appears to be actually no loss whatever of delicacy or sharpness. The superior fine ness of definition obtained on the collodion film seems to compensate for the inevitable coarseness of an enlarged image, and the result is an enlarged picture equalling in delicacy a print from a direct negative on albuminized paper. Finally, a properly treated collodion print seems from experience to give the greatest promise of permanency of any method of silver printing. For the purpose of completeness we may briefly restate the conditions and manipulations necessary, although many of them are known to many of our readers. The Negative most suitable for this purpose should be delicate, fully exposed, well defined, not too intense, and free from defects. A negative possessing sufficient vigour for printing on albuminized paper may be used, but will require management. The kind of negative used for solar camera enlargements answers well; it is better unvarnished. The Collodion should possess good body, and yield a tough film. Most good samples of bromo-iodized collodion will answer the purpose. A couple of drops of a saturated solution of wax in ether to each ounce facilitates final transfer. The Glass should be clean and free from scratches or defects. To facilitate the final transfer, its surface should be treated with a saturated solution of beeswax in ether, and then well rubbed with a linen cloth. The Nitrate Bath should be in good order for ordinary work, and be free from any disposition to fog. A Camera or Copying-box similar to that we recently de scribed for transparencies is used for the printing process. A portrait lens, or a triplet, with a stop sufficiently small to give perfect definition all over, should be used. The Exposure is an important element in securing good results. A full exposure and short development are best ; if protracted development is required to bring out half-tone, the image is apt to be buried, and the picture looks dull, and lacks detail in the shadows. At the same time, it should be remembered that over-exposure and under-develop ment tend to the production of an image lacking force and contrast. The Development is important. Either pyrogallic acid or protosulphate of iron may be employed; but as the ex perience of most photographers is chiefly confined to the latter, we recommend its use. A weak iron solution with a large proportion of acetic acid is best; say a 10-grain iron solution with from 20 to 30 minims of acetic acid per ounce. The gelatino-iron developer, or a developer containing sugar or honey, answers well. The development should be moderately rapid, and under no circumstances should it be