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November 12, 1880. J THE PHOTOGRAPHIC NEWS. 541 UhePhotographit Elehs, Tobember 12, 1880 PHOTOGRAPHY IN AND OUT OF THE STUDIO. TIE Vienna International PHOTOGRAPHIC Exhibition— Collotype Printing Process—Rose-Coloured ALBU- menized Paper—Blisters in Albumenized Paper. Thu Vienna International Photographic Exhibition.—Three weeks ago we gave an account of the approaching Vienna Exhibition, and expressed the hope that portraits and land scapes would be put rather more in the foreground than they were in the Belgian Exhibition. Now we have received the programme of the Austrian Exhibition, and learn from it that we had been greatly mistaken in our expectations. Landscape and portrait photographs seem to be excluded. In the programme, historical pictures are announced, illus trating the development of different photographic processes— also heliograpby, Woodbury process, Lichtdruck, photo lithography, photo-zincogrephy, applications of photo graphy to art, manufactures and schools, instruments, new photographic processes, and works illustrated by photo mechanical processes. Not a word is said about portraits or landscapes. Prizes are also offered—viz., silver and bronze medals and certificates of honourable mention ; but portrait and landscape photography is not mentioned in the prize lists, so that it has more the character of a photo-mechanical than a photographic exhibition. Collotype Printing Process.—Collotype printing is practised little in England and France, but much in Germany. The collotype process may be said to have been invented at Metz, by Tessie du Motay, but it was im] Others recommend the use of alum, &c., in the silver bath, the action of which is somewhat doubtful. A manufacturer informs us that the reason why more complaints are made now about the quality of albumen paper than three years ago is, because nowadays weak baths are generally used. This is no doubt true to some extent, for formerly printing baths of 80 grains were in vogue, while now baths of about 40 grains are in general use, and it may be concluded that the albumen is better coagulated with the stronger bath than with the weaker; but, on the other hand, it must be re membered that the albumenized paper now in the market ' contains much less chloride than that manufactured ten | years ago, and therefore a strong bath is on that account no I longer necessary. Even with strong baths blisters are not I avoided in all cases. It seems to us that the blisters must arise when the adhesion between the albumen film and the paper is not strong enough. It may be that spots of greasy matter in the paper interfere with the adhesion of tho albumen solution, and on these spots blisters are formed. The following is a very convenient method for avoiding blisters, which has given us excellent results: a solution of eight grains of chloride of sodium in an ounce of water is prepared, and the plain albumenized paper is floated on its back in this bath, until tho albumen film becomes smooth, which is easily observed by feeling ; then the sheet is dried in the usual manner. The paper is softened by the water in this operation, and therefore the albumen impregnates the pores better. A chloride solution is used, because with pure water the paper would lose some of its chloride. PITTING OF GELATINE PLATES. BY W. BARRY. Since my communication on this subject, last week, I have had occasion to use some emulsion hurriedly—that is, I had to wash and melt, and use at once ; when, to my surprise, I licences for working the process. A number of photo graphers obtained the latter, but nobody works any longer with it. The American climate, by reason of its extraordinary changes between damp and dryness, may probably put more difficulties in the way of its working than the English. Lichtdruck is used in Germany in many cases for repro ducing maps, but in most cases photo-lithography is pre ferable for this object. The stone can always be retouched ; corrections can be made to a great extent, which is not; the case with Lichtdruck. The importance Lichtdruck has obtained in Germany is best shown by the fact that there are three German handbooks on Lichtdruck, two of which are in the second edition. Rose-coloured Albumeniud Paper.—The employment of rose- coloured albumenized paper for silver prints is increasing. It is well known that this paper is coloured with fuchsine, which changes very quickly in daylight, so that tho rose colour fades very soon. Trapp has now prepared a rose- coloured albumen paper, which is not changed by light. This paper seems to be coloured by alizarin; we have exposed it eight days to sunlight, and observed no change at all. This reminds us that not only rose-coloured albumen paper, but also purple collotype, fades in the light. Purple collotypes are printed with a fatty ink containing crimson lake, and it would be better to substitute alizarin for the latter. Blisters in Albumenized Paper.—Blisters generally occur in as the Continental, because it is damper ; but, on the other hand, we are informed that the “ Lichtdruckers ” in Munich get the best prints if the weather is a little damp. It is further said that few Lichtdrucks are prepared in England, because only limited ordeis are given for them. If orders for Lichdrucks were given, it is said, then Lichdrnck estab lishments would not be wantiug. But we know that there are twenty presses in action in the collotype printing section of the Autotype Company, and thus there is already a call for the collotype in England. We hear that in Germany the collotype printing establishments are occupied generally with—(1). Illustrations for artistic or scientific works. There are a good many of such works in Germany, illustrated in this way. (2). Reproductions of old engravings or pencil drawings. The engravings of Drer, Holbein, Rembrandt, and others are reproduced very accurately and cheaply by Lichtdruck. (3). Taking pic tures of specimens of ancient and modern art industry. All the first rate works in wood, bronze, iron, &c., which are exhibited in the art industrial museums of Germany, are reproduced by Lichtdruck, anil many thousands of those pictures are used by art students and workmen. (4). Taking pictures of landscapes and architectural views. A great many of the pictures purchased by travellers on the Con tinent arc silver prints, but many of the larger architectural views sold in Germany are collotypes, and they are so similar to silver photographs, that anybody may mis take them ; very often shopkeepers sell them as ordinary photographs, and, curiously enough, deny that they are collotypes. A great many of these architectural views are used for study in architectural schools. No pictures will ever be prepared so cheap as those by Lichtdruck, and in consequence orders for Lichtdruck establish ments will never bo wanting. At present tho Licht druck is not used for portraits. A year ago strenuous endeavours were made to introduce tho Lichtdruck into portrait ateliers in America. It was called “ Artotype ” there. A company of shareholders patented it, and sold summer, but it happens sometimes that they appear also I in cold weather. Much has been written on this subject, 1 and the matter does not seem to be quite settled yet. Some iprovedand made of 1 photographers use four or more different fixing baths if they practical application by Albert of Munich. We are have blistering paper and make each a little stronger than informed that there are about forty collotype printing the next; thus with four baths of 80, 50, 25 and 12 grains establishments in Germany, about ten in France, and per ounce, they would fix the print in the first, and then put scarcely half a dozen in England. It is said that the it in the other three in succession. Other photographers English climate is not so favourable for collotype printing ' prefer to use only one.yery weak fixing bath (about 20 grains • ~ - - - • - r • ° per ounce). In a bath as weak as this, the pictures must remain about half a hour before they are completely fixed.