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

October 23, 1868.] THE PHOTOGRAPHIC NEWS. 515 suppression of information about which there should not be a moment’s dispute. Is it true that salt is used by the handful, rather than by the ounce ? I have heard such wild statements made, but have not hitherto believed them.—Yours sincerely, X. DISTORTIONS AND PERSPECTIVE. Dear Sir,—Your correspondent, “ John Anthony, M.D.,” in his letter on the above subject in your issue of last week but one, falls into error. He says :—“ If you stand at a distance of twelve foet in front of a mirror, you seo yourself as a spectator would see you who was twenty-four feet from you, or just as much behind the mirror as you are in front of it; if now you stretch your hand horizontally towards the mirror (cal) it thrpe feet in advance of you), your hand will look to you enlarged ; and well it may do so, for though it ought to appear as it would to a spectator at a distance of twenty-one feet, it will really look to you as if you had pushed it forward a distance of six feet; in fact, as if it was seen with the perspective enlargement of an object which was eighteen feet off the supposed spectator.’ ’ This is a mistake ; it would look as it ought to do ; viz., as if it were twonty-ono foet from your eyo, because your oyo is situated, not at the tip of your finger, but in your head, which is three feet behind said tip, and therefore eighteen plus throe foot from reflected imago of hand.—Yours truly, D. WrSTANLY. Ualk XU tbe Studio. Tub PiroTOGRAPHic Society’s Exhibition.—Our readers should not forget that the winter session of the Photographic Society will open with an exhibition, as it did last year, to which all photographers, members and non-members, are in vited to contribute. It will, as before, be held in the Archi tectural Gallery, 9, Conduit Street, opening on the evening of the 10th of next month. Members, their friends, and exhibitors will bo invited to a social reunion, similar to that held last year, which proved so pleasant. The exhibition will remain open for a week. We shall have something more to say on the subject in our next. Polytechnic Exhibition.—Amongst several very attractive novolties recently introduced at the Polytechnic Institution in Regent Street, is an interesting and capitally illustrated lecture by Professor Pepper, on the late total eclipse of the sun, to which we especially commend the attention of our readers. An old German story is made the vehicle for introducing some of the startling optical effects which have during the past two or three years made the Polytechnic famous. A musical and scenic history of the Maid of Orleans gives occasion for the introduction of some of the finest lantern effects wo have seen, both from photographic and painted slides. The other attrac tions—all excellent—are more numerous and varied than we can describe hero. Carbolic Acid in the Bath.—A correspondent says :—“ I have tried carbolic acid added to the negative bath as recom mended, and find it admirable in its effect, fully answering the purposes of additional rapidity and cleanness. I use, however, more than a trace; in fact, about the same proportion, or more, as I should nitric acid—i.e., about one drop to ten ounces of bath." Photographic Art Studies.—Our contributor, “ Respice Finem," recently lamented the small appreciation and limited sale of such art studios as those of Mr. Rojlnnder. Wo were glad to learn from that gentleman, in a reiut conversation, that the sale of his various published pictorial photographs has recently become very brisk ; so much so that ho had dif ficulty in keeping up the supply. Our readers will share in our pleasure on learning such a fact. Wo hope, for their own sakes, that a largo proportion of such pictures are bought by photographers. PIOToTYPY.—Wo have received from Mr. Fruwirth some specimens of his method of phototypy which admirably illus trate its capacity for some forms of art reproduction. An enlarged copy of an engraving entitled the “ Two Grand mothers ” is very excellent. The original is a print 9 inches by 8 inches; the phototype is about 13 inches by 10, inches; and the rendering is clean, delicate, and perfect in a high degree. PHOTro-LITHOGRAPIIY.—We have received from our excellent confrere, Herr Schrank, editor of the Austrian photographic journal, the Correspondenz, a very fine and enlarged example of photo-lithography, from which we glean that they have advanced further in Vienna in rendering half-tone perfectly by photo-litho graphy than wo have done in this country. The subject is a re production from a painting entitled “ Die Lustigen Weiber von Windsor ” (" The Merry Wives of Windsor”), rendering the scene in which Sir John Falstaf is being packed into tho buck basket. The photo-lithograph is in size 16 by 12, and is well rendered in every gradation by an exceedingly fine grain, which gives the effect of half-tone perfectly. Tho names of the photo-lithographers appended are Reiffenstein and Rsch, Ul Gorresponeuts. Northern Light sends us tho following:—" Keeping and Dating Bronio-iodized Collodion.—Statement for opinion of Editor of tho Photographic News.—Seeing your two articles on the above subject in the News of Juno 28 and October 11, list year I at once sot to work to try my hand at tho collodion iodized as therein set forth, and proceeded as follows:—-No. 1. Having some of Keene’s plain collodion in stock, I made up tho iodizer for 15 ounces:— Iodide of cadmium 100 grains Bromide of cadmium 30 ,, Dissolved in 5 ounces alcohol, sp. gr. 820, and added to tho 15 ounces plain collodion—12th December, 1867. No. 2. To 15 ounces of Rouch's plain collodion I iodized with— Iodide of cadmium 90 grains Bromide of cadmium 30 „ Dissolved in 5 ounces alcohol, supplied by Rouch, and added to the plain collodion—25th December, 1867. I kept the lot in a dark and cool pantry, and tried both No. 1 and No. 2 last June, and found foggy negatives, but, otherwise, indications of good nega tives ; rather dense in tho face, hands, and light drapery. Tried both No. 1 and No. 2 last week, and found again foggy negatives. Consulted Hardwich’s Photo. Chemistry, and then added alcoholic tincture of iodine to the samples No. 1 and No. 2, and then found clean, clear negatives, but very much thinner and more like glass positives. The collodions, before the adding of tincture of iodine, were both colourless, and after tho addition, straw colour. I expect that keeping the collodions for other six months or so might remove tho tendency to fog; but as I want a bottle or so for imme diate use, I beg to ask you whether you can oblige me with any other mode of treatment than adding the tincture of iodine, which seems to reduce tho density of the negative rather too much. I can seo from the indication beneath tho fog that time will give mo a most excellent collodion, only I fear it will be perhaps too dense in the whites and rather inclined to solarise. I am therefore anxious to know whether this tendency would bo removed if I was yot to add some more bromide of cadmium, or what other treatment will help it.” [There are various modes of dealing with the collo dions described. In tho first place, tho tendency to fog might have been removed and tho vigour retained by adding a smaller proportion of tincture of iodine; or, without altering the collodion, the tendency to fog might have been removed by adding a slight trace of acid to the bath; or, without altering either collodion or bath, the tendency might have been removed by adding a little more acid or a trace of gelatine to the developer. The tendency to excess of density in the lights would be best removed by giving a little fuller exposure, and avoiding prolongation of the develop ment. It is probable that a slight modification of tho developer and of •the manipulation in development would prove the most desirable remedy. It is probable that a little longer keeping will make tho collodions perfect.] “ Best Means to reflect Light for the Opaque Side of Interior of Studio.—I find great difficulty in getting tho shadows on my sitters softened to suit general taste and wish to know whether any other article than a white calico screen has been tried with success. I have heard of screens covered with tinfoil: have such been found good ? I may say t hat it is quite possible. My side-light—northern aspect—doos not extend far enough from the sitter, and so the light will come in a sharper angle, and so have the greater tendency to make deep shadows on the face. My total length of side-light is twelve feet, tho windows coming close up to background. I have then about three feet of this screened off, just beside the side of the sitter, and leaving about eighteen inches of clear glass next the background, to give the effect of light streaming in at open window side slip,