The photographic news

• Bandzählung: 29.1885
• Erscheinungsdatum: 1885
• 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-id1780948042-188500006
• PURL: http://digital.slub-dresden.de/id1780948042-18850000
• OAI: oai:de:slub-dresden:db:id-1780948042-18850000
• Sammlungen: LDP: Historische Bestände der Hochschule für Grafik und Buchkunst Leipzig
• Sammlungen: Fotografie
• Bemerkung: Seite I-II fehlen in der Vorlage. Paginierfehler: Seite 160 als Seite 144 gezählt.
• Strukturtyp: Band

• Digitalisat: SLUB Dresden
• Strukturtyp: Ausgabe

MARCI 13, 1885.] THE PHOTOGRAPHIC NEWS 175 very much admired ; and Mr. Brook a new lantern, which was tested in the usual way ; after which the meeting closed. Sheffield Photographic Society. The monthly meeting was held in the Masonic Hall on Tuesday, March 2nd, Mr. W. Hatfield in the chair. The minutes of the last meeting having been read and passed, Mr. 0. S. Platts was elected a member. A discussion on the selection of a resort for the first trip ended in favour of Wyam and Froggat, to take place early in April. Messrs. W. Johnson and H. Rawson, who were elected to purchase a lantern for the use of the Society, then brought forward a beautiful one with all the latest improvements, which seemed to give entire satisfaction, and the April meeting night was fixed to try it with slides of the members’ own making. Owing to the great amount of business which had to be done, the subject for the night, which was “Lantern Slide Making by Various Processes,” was only briefly gone into by the Presi dent and several other gentlemen. Imperial Russian Polytechnical Society. Photographic Section. The ordinary monthly meeting was held on Monday, Feb. I Oth, Lieut. Gen. Birkin, President, in the chair. There was a large attendance of members. The minutes of the previous meeting having been confirmed, The Chairman called upon Mr. Chesterman to communicate what data he bad been able to collect upon “ Balloon Photo graphy.” The speaker touched upon several experiments that had been made abroad, and showed a sketch of a camera on Mr. Woodbury’s principle, for use with a captive balloon ; he also ex plained Mr. lsdale's method of employing free balloons with clock-work adjustment for regulating the time of their descent. Further, thanks to the courtesy of Mr. Cecil V. Shadbolt, he was able to show several photographs, taken from balloons by that gentleman, which were much admired, as it enabled the members to form some idea as to the degree of distinctness obtained at different altitudes. A discussion ensued as to the utility of captive balloons for military purposes, and General Timascheff was of opinion that owing to the angle of view, it would be difficult to compute dis tances with anything like accuracy ; he therefore advocated Mr. Elsdale's plan, although the calculation of air currents and force of wind would be no easy matter. The Secretary handed round some prints on a new rapid print ing paper of his own preparation, aud proceeded to demonstrate the process. He explained that printing on gelatino-chloride of silver was very fully treated in the work under that title, by Messrs. Eder and Pizzighelli, to which he referred the members. After experimenting for over six weeks, the following formula had given him the best results :— No. 1.—Nitrate of siiver 100 parts Citric acid 100 „ Water 1,000 „ No. 2.—Chloride of sodium 35 „ Bromide of potassium 25 „ Gelatine 40 „ Water 1,000 „ Mix both solutions together at a temperature of 60° C., then add 250 parts of Heinrich’s gelatine, previously soaked in water. When set, press through canvas with meshes of 4 millimetres then the shreds of emulsion will only require an hour's washing in running water. After washing, re-melt and add 60 grammes of glycerine; then coat paper of an even texture, previously damped, and the edges turned up to form a tay. In answer to one of the members, he said that he did not use foreign Paper, but had taken a sample which, after testing several bands, gave the best results for accurate measurements with the different recording instruments at the Physical Observatory ; i.c., the ex pansion was very slight. The developer was made by using equal parts of a solution of 20 grammes oxalate of potassium and T3 of bromide of potassium in 100 grammes of water, and a 5 per cent, solution of ferrous sulphate, Containing a trace of citric acid. After development, the prints are put in a strong solution of alum, well rinsed, and toned in a bath made with— Acetate of soda 15 parts Water ... 500 Chloride of gold ” and a minute portion of chloride of lime ; finally fix’in hypo. (1 in 7), wash, and squeezee on to glass polished with French chalk. A Member said that he had used some paper of English manu facture, and found it full of pinholes ; this, it was said, was the fault of careless manufacture. After stripping some previously developed pictures, the Secretary asked the members to adjourn to the studio, where he would expose and develop several pic tures ; two minutes' exposure to the light of a paraffin lamp was found sufficient. Several sheets of paper having been dis tributed for trial, the proceedings terminated with a hearty vote of thanks to the Secretary. Leeds Photographic Society. The usual monthly meeting was held on Thursday, March 5th, Mr. Washington Teasdale, F.R.M.S., in the chair. After the confirmation of the minutes and other formal business, Mr. Thos. W. Thornton said the 'sub-committee appointed to arrange for the Lantern Exhibition and the Technical Lantern night had desired him to draw the attention of the members to one or two points which appeared to them neces sary in order to make future exhibitions more successful. The first was the size of transparencies. In his opinion the best size was 34 square, for although slides made on quarter plates could be exhibited, yet the four condensers usually found in lanterns would only illuminate equally a circle of about three feet diameter, and it appeared to him to be incurring extra cost and weight without any corresponding advantage. Then all slides intended for exhibition should be properly marked, the one in general use being three inches and a quarter outside, and two inches and three-quarters inside. The reason of this would readily be seen when it is remembered that it is usual to place the lantern in such a position that a properly marked slide will just fill the screen. It very frequently happened that a series of slides would be completely spoilt by one or two that were, on account of their density or other defect, unfit for exhibition, and this, he thought, was caused by the fact that many of the mem bers were new to lantern slide marking, and therefore were not in the best position for judging as to what would look well on the screen. He suggested that all slides intended for exhibition should be delivered to a sub-committee composed of lantern experts, at least fourteen days before the date of the exhibition, so that they might have the opportunity of leisurely examining each slide, and select for exhibition such as they thought suit able. The experience they had gained at the recent exhibition was not only instructive, but had also been amusing. Notwith standing the request that all slides should be delivered some time previous to the exhibition, many were handed in after the exhibition had commenced; some were numbered on the black paper forming the mark, and arranged in anything but consecutive order. There are only eight corners on which a slide can be marked, and the exhibitors had utilized six out of the eight; others were not marked at all, and most of the instruc tions as to the meaning of the various markings were given verbally, and during the exhibition. It was suggested that all slides should be delivered, as previously suggested, some time prior to the exhibition, placed in grooved boxes, numbered, and arranged consecutively, and each one distinctly marked in accordance with the rule laid down by the Photo Club, i.c., that each slide shall bear on its face two white patches, one on each upper corner. By the face of the slide is meant that side which, when held next to the eye, shows the picture or any reading the right way ; and above all, that all slides not sent in accordance with the regulations laid down by the committee should be ex cluded. Two oxyhydrogen lanterns fitted with twin conductors and objectives having been placed in a suitable position for throwing two 5-feet discs side by side on a screen, in each series of slides the negative was first exhibited, and its general character commented on, and then slides made from the gelatino-bromide process, gelatino chloride, direct printing, collodion, washed emulsion, and collodion emulsion with beer preservative, were submitted for the judgment of the members. The majority appeared rather to disregard the question of colour, and altach more importance to other qualities. The slides on gelatino-bromide plates were consideced the best; but in several instances these were closely run by chloride plates and washed emulsion. The colour of the latter elicited much ad miration from some of the members. The Chairman said he should hardly like to say there was any best process of preparation, so much depending on the skill