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JOLy 2, 1880. I THE PHOTOGRAPHIC NEWS. 313 Ue A yotographic Tcs, Euly 2, 1880. PHOTOGRAPHY IN AND OUT OF THE STUDIO. Difficulties in Photo-Surveying—The Awards of the Sydney Exhibition—A FRESH-WaTER Medusa. Difficulties in Photo-Surveying.—In a communica ¬ tion to our pages, Lieutenant Darwin makes known some of the difficulties attendant on surveying with the aid of the camera. The advantage claimed for the employment of photography in this connection is, above all, expedition, and. on the face of it, there certainly seems no reason why the collodion or gelatine plate could not record observations more quickly and truthfully than the eye. In theory it is hard to see where any hitch can be. The far-seeing lens with its sharp and accurate observations should surely be able to appreciate all that the eye can discern, while the sensitive film is only too ready to record anything that may happen in its field of vision. But when we come to practically employ the camera, we do not find the matter so easy. In the first place, we are given a station, and directed to take (say) certain views in different directions. The first negative succeeds ; the atmosphere is clear, we can see the far hills in the dis tance, and the light shines exactly as it should shine in order to secure sharp detail and definition. The rays of light strike the heights in front, at an angle of something like 45°, and under these circumstances we are able to secure a perfect picture. But now we have to proceed with No. 2 view, and it is required to alter the direction of the camera. If the object to be photographed were bold and near at hand, it would not, perhaps, so much matter ; but it is distance to which we have to give our attention, and delicate distance requires to be very well lighted. When developed we get a flat picture, with an objectionable haze, through which everything is seen but indistinctly; or, may be, if we are not careful, we only get foreground and no distance at all. It is true there is a remedy for this. We may wait between the taking of the views, in order to let the light get round ; but then we lose valuable time, and the main advantage we were to secure in using the camera has gone. Again, landmarks which are very visible with the light shining in one direction may be almost invisible in a second photograph. Landscape photographers all know what a difference the angle of lighting has upon the appearance and shape of an object, and even its height is sometimes apparently altered ; and when we remember that it is the accurate rendering of certain objects in the camera upon which the photographic surveyor depends, the im portance of this matter will at once be seen. Another point, not less important, that Lieut. Darwin men tions, is the choice of a lens for the purpose. As he says, the best lens, of course, is one of long focus. A long focus lens is the only one that will do justice to the land marks you have chosen, and render these upon the photo graph in a clear and intelligible manner. But the use of a long focus lens involves difficulties. In the first place, you must take a large number of views to complete the panorama. No less than ten would be required, and as three fixed points are necessary in each picture, the work of triangulation would be considerable. Thirty fixed points would in this case be necessary, and we quite agree with Lieut. Darwin, when he says that to get fifteen clearly visible stations is quite difficult enough. Therefore the photo-surveyor abandons the long focus lens, and chooses one embracing a wider angle. Employ ing this instrument, he can manage to complete the pano rama in five views, requiring for the work fifteen stations ; but how unsatisfactory photographs taken in this way must be for surveying purposes is obvious to all. The Chevalier plane table, to which Lieut. Darwin in. cidentally refers, is, perhaps, the most perfect photo. surveying instrument that has yet been devised. It is a misfortune that the instrument was barely completed before the death of its inventor, for M. Chevalier might possibly have given us a more practical instrument. It is one that has been employe! both in this country and abroad, but the very limited use made of it shows that there is something wanted to bring it into everyday use. M. Chevalier was considerably encouraged in his work by the late Emperor of the French, and at the time of the inventor’s death he was engaged in making a modification of the photographic plane-table to render it applicable for siege-work, so that by its means the fire of a battery might be directed with the same certainty at night as by day. The Awards of the Sydney Exhibition.—The awards of the Sydney Exhibition have been made. There were four classes of awards, it seems, and all four have been con ferred. Colonel Stuart Wortley is fortunate in receiving the honour of the first class, his well-known masterly views of sea and sky no doubt having secured it him. The Colonel, we believe, is attending the Exhibition in an official capacity as a delegate from South Kensington, and it will be doubly gratifying to him, therefore, to be on the spot to receive the award personally. We con gratulate, too, Messrs. Marion and Co., who have had the good fortune to secure an honour of the same degree. In the second class, Mr. H. P. Robinson, of Tunbridge Wells, and Mr. R. Slingsby, of Lincoln, receive recogni tion, and from this fact we must either suppose that pic torial and portrait photography at the Antipodes is far in advance of the art in England, or that by some mischance our masters at home failed to be appreciated. Mr. York’s name we are always glad to welcome, and if it is his trans parencies that have gained the award, we know that he well deserves it. Mr. Frith’s views gain him also an award of the second class, and Mr. Weiller secures a similar honour. Mr. A. L. Henderson, who is well known to be facile princeps in the matter of enamel photography, does not receive more than a second class award either, but he may console himself by the fact that he is iu very good com pany. We have never seen any photographic enamels from Australia, but since Mr. Henderson’s are only considered worthy of a second class award, we anxiously look forward now to the fine work of our far-off brethren. Mr. Hedges receives a third award, presumably for his clever cattle studies; and Mr. E. Debenham is put in the same class. Mr. H. Manfield, of Northampton, receives an award of the fourth degree. A Fresh- Water Medusa.—Considerable excitement has prevailed among naturalists during the past month owing to the discovery of a new animal in the ponds of the Botanical Gardens. The Secretary of the Society appears to have found what turns out to be a sort of fresh water jelly fish, and very impartially sent specimens of it round to various gentlemen whom he believed would take an interest in the discovery. The result has been a series of high pressure; investigations and papers, each savan vieing to be before the other to give attention to the little animal. One investigator worked both night and day, and so was enabled to beat his brethren by several hours, furnishing the animal with a name, and thus adding a finishing stroke to his work. But a cry of “ not fair ” appears to have been raised by others in the race, and the fresh water Medusa will most likely be re. christened. In the meantime one naturally asks, what has become of the original discoverer in all these efforts to connect one’s name with the new-found jelly-fish? What squabblers naturalists are, to be sure ! Photographers never make such a fuss when they get hold of a fresh-water Medusa ? Messrs. Hyatt and Hyatt, of Portsmouth, send us a little carte almanac, an example of enamelling quite equal to that of the Paris houses which make) the Mrte entailUc a speciality.