The photographic news

• Bandzählung: 11.1867
• Erscheinungsdatum: 1867
• 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-id1780948042-186700008
• PURL: http://digital.slub-dresden.de/id1780948042-18670000
• OAI: oai:de:slub-dresden:db:id-1780948042-18670000
• Sammlungen: LDP: Historische Bestände der Hochschule für Grafik und Buchkunst Leipzig
• Sammlungen: Fotografie
• Strukturtyp: Band

• Digitalisat: SLUB Dresden
• Strukturtyp: Ausgabe

He was uncertain whether this would be a real or only an apparent advantage. Mr. Solomon read some remarks to the effect that Mr. Dallmeyer’s new lens resembled the doublet of Mr. Grubb in general form, the chief novelty being that the back lenses were not cemented, and had facility for separating them, so as to diffuse the focus. Mr. Hughes said the discussion seemed to have a singular tendency to depart from the subject before them, and bring up subjects discussed and settled at a former meeting. The question before them was the new lens introduced by Mr. Dall- meyer. It had been pointed out that in some respects this lens resembled other lenses, only differing from them in this power of separating the back lenses, and so producing depth of focus. Now this little difference really embraced the whole question. Opticians had hitherto aimed to produce exclusively sharp lenses, and photographers had been driven to various shifts to gain diffusion. Mr. Dallmeyer came forward with a great innovation, and said, “ I will give photographers a lens which can be employed so as to give perfect sharpness, but which can also be made to give any amount of deviation from sharpness, the responsibility for the kind of definition employed resting on the photographer, and depending for its excellence on his skill and judgment.” The merit chiefly claimed for the new lens was this. It was alleged to be as good as the best existing lenses, and to have, indeed, some general points of superiority ; but its chief claim was, that it put this new power into the hands of the photographer himself. Hitherto opticians had acted as an artist’s colourman might do if he insisted that painters should only use fine-pointed pencils for whatever class of work they required. Mr. Dallmeyer’s point was, that photographers who wished for soft and diffused definition should have an instrument which would give it to them ; whilst those requiring extreme sharpness should have the means of securing that. After all, it would continue a matter of taste and judgment. Some subjects would require sharpness in everybody’s hands. Some photographers would insist on having it in all cases; others would prefer a soft suggestive picture, free from sharpness. Here the power was given to each to secure his own class of results, and be solely responsible for them, the responsibility no longer resting on the optician. It might be that some might prefer Mr. Claudet’s plan as well. If so, let them use it. But if diffu sion could be obtained by simpler and less troublesome means, by all means let them avail themselves of that first, and then, if it failed in giving all they required, it was always open to them to supplement it by Mr. Claudet’s moving focus. Mr. Debenham exhibited a diagram, and made some remarks to the effect that a perfectly corrected lens had one plane perfectly sharp, the planes in front and back gradually passing out of focus, or from a point to a disc or circle. The same sized lens with spherical aberration would simply have no point in focus, and would proceed from a circle to still larger circles. In short, that whilst the latter would have no point perfectly sharp, the distant planes would be in no respect better defined than by the perfectly corrected lens. Mr. Hughes suggested that Mr. Debenham should proceed to show the practical relation of his remarks to the subject before them. Mr. DALLMEYER proceeded to reply. He agreed with Mr. Claudet in referring the matter to practical results, and con fidently invited comparison between the pictures produced by Mr. Robinson, Mr. Hughes, and others, with his lens contain ing optical diffusion, and those by Mr. Claudet’s plan of moving. He willingly gave the highest credit to Mr. Claudet for the skilful application of his plan of moving, which had failed in the hands of others. He must repeat his conviction, however, that in a picture there should be certain parts better defined than the rest. Absolute equality of definition was not desirable. The eye and its markings ought to be sufficiently indicated; and in the pictures he now placed on the table this was so, but was absent in those of Mr. Claudet’s. Again, the moving plan could not be successfully applied, because the time of exposure could rarely be determined accurately beforehand. Changes in the light, movement in the sitter, &c., might often induce the photographer to shorten the exposure, and endeavour to compensate in development, &c.; and when this was the case, a steady movement of the lens—so as to bring the focus on all the planes—would be impossible, and a pause at any part would produce a distinct impression instead of a general soft ness. In answer to Mr. Reade’s question, he might say that he had distinctly stated in his paper that in any separation of the components of the old combination portrait lens, coma was pro duced in the marginal definition; and it was one of the points of his lens that the separation proposed did not produce coma, circles remaining circles throughout. Mr. Davis was perfectly correct in saying that sharpness would not be necessarily incom patible with softness, but that would only be the case in defining a plane surface. But in defining a solid body it was different. In reply to Mr. Solomon, as to the points of novelty in his lens, his claim was this : that the back combination was uncemented, that the adjacent surfaces were dissimilar, and that they admitted of separation for producing diffusion ; the whole being perfectly corrected and perfectly sharp when screwed home. He believed that no such portrait lens had ever previously been made. The aim was, as Mr. Hughes had said, to place the power and responsibility in the photographer’s hands, and let the results depend on his artistic skill, any degree of sharpness or diffu sion being within his power. In relation to as much as he could understand of Mr, Debenham’s remarks, he seemed to have overlooked the fact entirely that the effective power ot the rays was altogether altered by the diffusion of focus. He might easily satisfy himself, however, by reference to prac tical illustrations, when he would find that by such diffusion objects in planes wide apart were defined better, not simply relatively, but absolutely. The discussion then closed. Me. W. England then read an interesting practical paper on the preservation of negatives, and the revarnishing and modifying of intensity of varnished negatives. The Chairman said he was certain that all photographers would appreciate the valuable practical information contained in Mr. England’s paper, which, as its statements could not be gainsaid, did not admit of discussion ; he therefore proposed a most cordial vote of thanks to him. Also to Mr. Dallmeyer for his excellent and important paper their cordial thanks were due. Thanks passed by acclamation. The Chairman read a letter from Mr. Ross, accompanying some fine specimens intended to show that flare was not a characteristic of his doublet, as it was stated to be of all doublets at the last meeting. The Chairman said the pictures were very fine, and showed no signs of flare. The angle included was also very large. The Chairman also called attention to an example of Monk house’s Water Agitator, which was a very efficient aid in washing prints. A description would appear in the Journal. The Secretary read a letter from Mr. Wharton Simpson, stating some arrangements for sending photographs to the forthcoming Exhibition at Paris. The proceedings then terminated. Oorxesgondenre. ART AND PHOTOGRAPHY. Sir,—Allow me to submit to you a few lines upon a sub ject which should be of the past, and the revival of which seems very like Art versus Art. Surely a better feeling subsists between the photographer and the artist than might be supposed from the remarks occasionally made (not in a spirit of moderation) by some talented enthusiast. The artist is often indebted to photography, and it is palpable that the photographer should be an artist; thus their inte rests are becoming identical. The time has passed when the portrait painter looked with a jealous eye (and naturally enough) upon that which appeared likely to snatch his occupation from him, and the photographer, rejoicing in the power which the discoveries of great and scientific men had given to him, felt inclined to domineer over the artist, forgetting that his (the artist’s) talent came with great study and great application only; while ordinary photo graphy had been made, unfortunately, too easy, for any one could attain it. I say unfortunately, for the conse quence was, that many among its numerous practitioners were dishonourable and unscrupulous men, whose bad practices and want of integrity too frequently disgusted the public. It has often occurred to me that the cavilling spirit