The photographic news

• Bandzählung: 12.1868
• Erscheinungsdatum: 1868
• Sprache: Englisch
• Signatur: F 135
• Vorlage: Hochschule für Grafik und Buchkunst Leipzig
• Digitalisat: Hochschule für Grafik und Buchkunst Leipzig
• Digitalisat: SLUB Dresden
• Rechtehinweis: Public Domain Mark 1.0
• URN: urn:nbn:de:bsz:14-db-id1780948042-186800009
• PURL: http://digital.slub-dresden.de/id1780948042-18680000
• OAI: oai:de:slub-dresden:db:id-1780948042-18680000
• Sammlungen: LDP: Historische Bestände der Hochschule für Grafik und Buchkunst Leipzig
• Sammlungen: Fotografie
• Strukturtyp: Band

• Digitalisat: SLUB Dresden
• Strukturtyp: Ausgabe

JANUARY 3, 1868.] THE PHOTOGRAPHIC NEWS. 7 M. l’Abbe Laborde read a paper on the causes which, beyond the action of light, tend to alter the blacks and whites of photographic prints. He attributed a great deal of the altera tion to the deposition upon the print of a small quantity of mobile silver, which during the treatment of the print in the different operations is moved from one portion of the picture to another. To remedy this inconvenience M. l’Abbe Laborde recommends the employment of a bath, after the prints have been fixed, composed in the following manner, viz.:— Bichromate of potash ... ... 3 grammes Perchloride of iron ... ... ... 1 gramme Water .. 150 grammes In the Moniteur de la Photographic, M. Leon Moock reports progress with regard to the formation of an association of ope rators and others connected with the art of photography in Paris. By combining together, M. Moock is in hopes that the position of photographic employes will be notably improved, both from a moral and pecuniary point of view; he asks for immediate and energetic co-operation, both on the part of masters and assistants. La Science pour tous makes the following statement with regard to foggy baths:—“ Sometimes when the plate is removed from the bath it is found to have become fogged, and when the image is developed the latter is found to be quit® useless. M. Terry, who has carefully studied the question, asserts that fogginess is never met with excepting in baths containing im purities, and that it is an error to suppose that old baths are the cause of fogging, for experience has shown that baths of this description always furnish clear negatives. Old baths lose their sensitiveness, but have no disposition to fog. “ The real causes of this inconvenience are : firstly, the pre sence in the bath of small quantities of developing agents derived from the hands of the operator when coating a plate previously to its immersion in the silver bath ; and, secondly, the employment of alkaline collodion. It is well to prepare one’s own collodion, as all collodions of commerce are of an alkaline nature, and are incapable of furnishing negatives of a very transparent character. To prevent the apparition ot fog in negatives, it is merely necessary, therefore, after having pre pared a bath of the greatest purity, and renounced the use of alkaline collodion, to see that the hands aro perfectly clean during the operation of coating the plate, and to take care that the bath is always properly covered, so as to ensure its preser vation from any impurity. A correspondent of the Moniteur extols the beauty of the glazed leptographic paper, but recommends the coating of prints prepared from the same with a preservative solution after they have been toned and fixed, as during the operation ot mounting the prints are not unlikely to be injured. When, therefore, the prints have been washed and dried, they aro coated with albu men (half water and half white of egg) by means of a tuft of wool dipped into the mixture and drawn slowly over the surface to prevent the formation of froth and air-bubbles. After drying, the surface cannot be injured by friction, and the pictures gain considerably in brilliancy. M. Thomas writes in the Archiv that ho has been making a careful trial of Professor Towler's nitro-gelatine developer, but has been unable to obtain successful results. He believes that probably Prof. Towler has used a description of gelatine which he is unable to obtain, or possibly there may have been an error in the formula. The Photographuche Oorrespondenz contains an exhaustive article, by M. Alois Nigg, on the best method of building photo graphic studios. M. Nigg goes fully into all details, and ex plains his ideas by means of well-drawn diagrams. The Archiv recommends the lacquering of all zinc vessels used in photographic operations, as pictures manipulated there in aro apt to contract yellow stains when allowed to remain in contact with the metallic surface. In the Mittheilungen, M. Weber communicates a formula for obtaining a good negative varnish. It is as follows :— Best yellow shellac . 1 lb. Alcohol 2 lbs. Ordinary resin ... Venetian turpentine ... ... ... 1 oz. The shellac does not dissolve entirely, and the thick, turbid solution is filtered through coarse blotting-paper, a little more alcohol being added if necessary. To clarify it, the mixture must be allowed to stand for some time. It is poured over the plate in the usual manner, the latter being slightly warmed previous to the operation. M. Weber likewise makes known (in the same journal) a very simple means of copying and enlarging cartes-de-visite and other small photographs. By the employment of a very simple piece of apparatus he is able to prevent—at any rate to a very great extent—the mealiness and granular character generally presented by a copied or enlarged photograph. The apparatus he uses is a kind of box—or, more strictly speaking, a tray or trough of cardboard—the four sides of which slope inwards towards the bottom at an angle of 135°, and are covered with tin-foil; the picture to be copied is fixed at the bottom of the apparatus, and the whole hung up in the front of the lens. A photograph is then taken in the ordinary manner, when it will be found that the reflection obtained by means of the tin-foil from all sides will have the effect of securing a picture almost perfectly free from grain. At a recent meeting of the Berlin Photographic Society, M. Linde, of Gotha, exhibited a camera constructed to open and close by mechanical means, so that the period of exposure might be regulated with the greatest nicety and precision. When the time of exposure has been fixed upon, a hand is moved to the desired figure on the second dial, the camera is opened, and the clockwork set in motion ; the apparatus then closes of itself at the prescribed moment. The apparatus, which can be used with lenses of different sizes, can be con structed for £3. FIRESIDE MUSINGS. BY W. T. BOVEY. No. 3. Education and Quackery. Next to Fenianism, the question of education has become the sensational topic of the day, and the way to set about the serious task of reformation is a problematical nut that the teeth of no statesman have as yet succeeded in cracking; although, judging from the startling predictions that seem to be borne on the wings of every passing blast, the position is critical, and the quicker the kernal is withdrawn from its hiding-place the sooner will the fears of trembling Albion be dispersed. Why did that fussy French Exhibition so ruthlessly tear asunder the veil that concealed from the eye of egotism the near- approach of the “ tortoise ”? Why has it so unceremoniously dispatched the grey-bearded notion that education for the masses were broad-swords, barricades, and revolution concealed in sheeps’-clothing? Above all, why have our Continental'neighbours so conclusively shown that popular instruction yields new vigour to skill, strength ens the arm of state, and extends, whilst improving, the several fields of human industry ? To those who have en joyed the advantages of superior tuition it doubtless appears a mystery that England’s boast, a cheap press, which, with untiring energy, continues to send forth daily newspapers, weekly journals, and monthly periodicals by tens of thou sands ; that creates mountains of volumes on every conceiv able subject, and consumes as much paper annually as would carpet a continent, should, in spite of its Herculean efforts, have failed in making headway against the stream of ignor ance. But to the laborious few whose secret yet resistless impulses have enabled some of the formidable difficulties that accompany efforts at self-culture to be surmounted, the problem is one that admits of ready solution. For, startling as the statement may to some appear, the greatest clog on the mental labours of those “ who consume the midnight oil ” is a lack of teachers. True, of a certain class, they have preceptors whose name is legion, but how few among them who arc qualified to occupy the important positions they assume! How limited the number who strive more to smooth the path of "knowledge than to create “ mountains out of mole hills,” that their own superiority, magnified, might hurl a shaft of timid awe into the breast of the plod ding student I Ho! for teachers whose hearts are large enough to hold the spirit of philanthropy, whose armour of modesty and common sense is sufficiently stout to enable its wearers to do battle with those hydra-headed monsters, pre-