Volltext Seite (XML)
June 15, 1883.] THE PHOTOGRAPHIC NEWS. 383 enlargements, though he himself did not like the rapid plates. He did not think there was any reason why comparatively rapid plates should not be prepared without granularity. Mr. Foxlee observed that the grain in some of the bromide plates, especially the rapid ones, was very coarse indeed; of course, the effect of enlarging a very coarse film (say) from 4 to 16 inches, was very different from enlarging an 8-inch four diameters ; in the one case the grain would naturally look much coarser than in the other. Mr. W. Brooks showed some prints from negatives, some enlarged two diameters, and some four, in which he did not think much falling off would be found from pictures taken direct. He quite agreed with Mr. Foxlee that it was much better to enlarge two diameters than four, and he considered that a nega tive taken on a slow gelatine plate was better for enlarging than one taken on a rapid plate. He stuck to one process, the collo- dio-bromide, and had taken a 36-inch plate with better results than even with wet plates. Mr. T. Bolas thought that for moderate sizes it was prefer able to take pictures direct. Mr. Howard said it was very seldom they had an opportunity of seeing large photographs taken direct, but there was no doubt, he thought, that in taking a large picture, provided the subject admits of a long enough exposure, better results are obtainable direct than by enlarging. He endorsed Messrs. Taylor and Foxlee’s views as to the advisability of using albumen as a medium. Mr. Foxlee remarked that Mr. Vernon Heath’s negatives were all 12 by 10, and were enlarged about two-and-a-half diameters. He thought if the enlargement were only to be (say) 12 inches, the better plan was to make it as a transparency, and from that transparency to print the negative. This plan was much used for making small enlargements, and had at one time been sold as a secret process. Mr. F. A. BRIDGE exhibited some specimens of microscopic enlargements of diseased brains, enlarged from one to two thousand times, by Mr. Ayres. The Chairman said Mr. Howard had touched upon the size of the apparatus to be used. Some years ago they had had a dis cussion as to whether, by enlarging the camera, more correct direct images could be obtained, and he thought Mr. Taylor had then expressed an opinion that there was a limit to this, and that by going beyond a certain point they would only magnify the defects of the picture. He had seen in a notice of the Sydney Exhibition, there was one picture 36 inches long, which was asserted to have been taken direct. Mr. TAYLOR had a feeling against taking very large pictures direct. Mr. Cobb was very much surprised to find a feeling amongst photographers generally to run after sharpness and smoothness, he considered it was highly desirable to obtain the correct texture in their pictures, and never mind the smoothness. Mr. E. Dunmore held, with Mr. Foxlee, that within a certain size, direct pictures were certainly preferable to enlargements; he thought there was a delicacy about direct pictures which was missing in enlargements. Mr. P. Mawdesley was glad to notice a very general expres sion of opinion that for plates 10 by 8 or 10 by 12 the results were superior when taken direct, to those obtained by enlarge ment. He thought there were few amongst them who desired larger sizes than these, and he would prefer, in taking a moderate sized picture, to take it direct; but, after all, he thought it was a matter of personal convenience. He agreed with Mr. Cobb with regard to the tendency towards working to destroy natural effects, the result of which was that what should appear in their pictures as flesh, resembled marble. Mr. Smith said the question at issue was, would it be more desirable in the future to adhere to taking large pictures direct, which seemed to be generally acknowledged to be the best, or to try after improvements in enlarging small ones ! He thought there was room for the latter. Mr. HaLLIER thought that in taking a copy, even the same size, it could not be equal to the original, provided, of course, the original negative were a perfect one ; therefore it was much less likely that an enlarged copy would be as good as the original. Mr. Brooks showed two collodio-bromide negatives with the same exposure, one developed with alkaline-pyro, and the other with ferrous-oxalate, the latter having the appearance of five times the exposure of the former. The meeting then adjourned. North STAFFORDSHIIRE Photographic Association. A meeting of this Association was held at the Town Hall, Hanley, on Wednesday evening, June 6th. M. A. Humboldt Sexton occupied the chair. There was a good attendance of members, and a discussion took place upon the relative value of the wet collodion and dry gelatine processes in weak light. Mr. Potter found a wet plate almost as sensitive as a dry one, and obtained better results in a weak light; he preferred the wet process for everything not requiring a short exposure. Mr. Burgess concurred with Mr. Potter’s remarks ; he had obtained good wet plate negatives recently at and after 7 p.m. Mr. Potter, in reply to a question from a member, found in photographing interiors requiring a prolonged exposure, that the great disadvantage of a wet plate was that the film was apt to dry, and cause “ silver stains.” Mr. Alfieri had found, in using glycerine as a hygroscopic, that collodion films had a tendency to come bodily from the plate; he had in some cases prevented this by giving the plate a preliminary edging of shellac varnish. He had also noted, as a curious thing that in working in the field, the direction of the wind interfered with the flowing of the collodion (notably, an east wind). Mr. Potter, for landscape work, much preferred wet collodion, and asked the opinion of those present. Mr. Allison agreed with Mr. Potter. Mr. Alfieri said that if the question had been put to him a short time ago, he also should have agreed with the last speakers ; but that now, although an experienced wet plate worker, he had with proper alkaline development and dry plates obtained nega tives so closely resembling those by the collodion process that he considered one as good as the other. In reply to a question, Mr. Alfieri said that he used for his dark room window book-binder’s cloth; he had also found that in developing a plate, if it were left exposed to the ruby light during the whole time occupied in the operation, the same would be much retarded. A short paper being read upon “ Various Modes of Develop ment,” by Mr. Allison (see page 375), the Chairman asked whether, pre-supposing the use of alum, plates were as liable to frill under the oxalate as under pyrogallic development. Mr. Allison had found that plates liable to frilling were best developed with ferrous oxalate, after previously soaking them in alum and washing; and, in reply to another query, had found scarcely any appreciable difference, in developing negatives between the ferrous oxalate and ferrous citro-oxalate developers ; he thought that hydro-quinone gave more detail than pyrogallol’. After deciding to hold the next meeting at Stoke-upon-Trent, and Mr. Henk having been proposed as a member, the meeting was adjourned. Edinburgh Photographic Society. The eighth ordinary meeting of this Society was held in 5, St. Andrew Square, on the evening of Wednesday, 6th June, Mr. A. Craig-Christie, F.L.S., vice-president, in the chair. The minutes of previous meeting having been approved, Messrs. James Hay, James Cobb, W. G. Campbell, L.A., W. J. Cockerine, A. Stewart, David Watson, A. Ayton, jun., and Hugh Brebner were unaminously elected ordinary members of the Society. The evening was devoted to an exhibition of a large collection of transpirencies from micro-photographs. Mr. W. Forgan gave an interesting information as the various objects appeared on the screen. Mr. J. M. Turnbull successfully conducted the lantern manipulations. A most curious print from a negative by Mr. Annan was handed round, showing a double impression of the same view, as though two lenses of differing foci had been employed. The only explanation Mr. Annan could suggest was that by some means a duplicate image had been thrown on the plate from a large volume of steam not within the angle of view. Another plate taken under precisely similar circumstances, except that the steam was absent, exhibited no peculiarity. A c nversation took place as to the desirability of having an annu d trip and holiday, and it was ultimately decided to appoint Mr. M. Kean, Mr. W. Dougal, and Mr. Wardale as a committee, with power to add to their number, to find out the general feeling of members in regard to the matter. The usual votes of thanks terminated the proceedings.