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690 thing, the use of a plate larger than the lens U. to be made to cover. The exaggerated feet and hands—or even nose, and so forth, where a large head is taken—do not constitute true distortion, inasmuch as these portions of the person are represented precisely as they would appear to the eye of a person who would look at them from the same point as the lens is placed at. As a matter of fact, no person who had the means of retiring to a further distance would take up such a point of view, because he would only with difficulty get a general view of the subject if he did, the angle which it subtended being too great. Indeed, it may be said that, so far as the lens is con cerned, there is not in portraiture such a thing as distor tion brought about. It is true that certain lenses (and, among them, many portrait lenses) do give actual distor tion, straight marginal lines in the subject being shown as curved lines in the negative. This distortion is, how ever, so slight when the lens is used for a moderate angle, that in the case of a portrait it is quite inappreciable. If the angle of view be not greater than that given by a portrait lens of one of our best English makers, used on the size of plate mentioned by him, it is safe to say that even in the case of a large print, no point will be misplaced by as much as a hundredth of an inch. Actual distortion, although never the fault of the lens itself, may often be caused by the combined efforts of the lens and the swing back. The swing back, when used for architectural work, is generally employed merely as a means of getting parallel vertical lines in the negative, whilst the eamera is tipped so as to include all the view that is wanted. In portraiture, however, it is different. The swing back is used, as a rule, simply to get different portions of the sitter into focus, and is used quite regardless of whether or not it is kept in a vertical plane. We all know that of two lenses the longer focus one gives the larger image. Now when we use a swing back, this means that we have what may be styled different lengths of focus given by the same lens. The top portion of the plate will be further from the lens than the bottom portion, and the picture then will as a consequence be to a larger scale, or the matter will be vice versa. In either case, no one portion of the picture will be to precisely the same scale as another portion, and the result will be actual distortion. Such distortion only becomes very evident when it is added to the apparent distortion, which is, as has been explained, produced by the use of a lens of too short focal length. The true distortion is then at its greatest, and generally tends in the same direction as the exaggerated perspective which amounts to almost the same thing as distortion. The manner in which the paper on which prints are made stretches is, as is well known, the cause of an amount of actual distortion which is most noticeable. The paper stretches more in one direction than in the other, and if we print two copies from a negative of a large head, and let the length of one be cut parallel to the length of the sheet of paper, whilst the length of the other is cut parallel to the breadth, the difference in the finished prints is most noticeable. In fact, it will be remarked, even by one who is by no means accustomed to the critical exami nation of photographic or other portraits. The peculiarity is most of all noticable when the prints are mounted in optical contact with glass. The operation of so mounting is done when the print is wet, and the support does not give even to the small amount that a card does. This distortion is not confined to albumenized paper, but, at any rate at times, makes itself evident in the case of the paper from which carbon tissue is manufactured. Recently there was shown at a meeting of the London and Provincial Photographic Association, by Mr. W. E. Debenham, a species of actual distortion which we think will be new to many of our readers. aPHIC NEWS LNovEMBER 2, 1880 this form of distortion makes itself evident inthenega ! tive, and is peculiar to negatives taken with gelatine plates. ! It is caused by what can scarcely be called running of the gelatine, but to an action slightly akin to this. Many must have noticed that if the attempt be made to dry negatives by heat, even if the heat be far short of that which will produce running of the gelatine, a peculiar action takes place. This action appears to be due to a sort of surface tension of the dense portions of the image which have been hardened and rendered comparatively in soluble by the action of the pyro developer. These are, to a certain extent, drawn together, the result at times being a sort of chalkiness in prints taken from the negative. The effect is particularly noticeable in the case of a nega tive in which there have been transparent pin points in any of the high lights. These pin points were perhaps almost invisible before the heat was applied. When the plate is warmed, the film appears to be drawn together as described, and is drawn from the transparent spots, leaving them much larger, and in fact often rendering useless a negative which would otherwise scarcely have suffered from the pinholes. In the example shown by Mr. Debenham, the action had not gone the length of causing chalkiness in the lights, or, indeed, anything which would at first sight have been termed distortion; that is to say, no one simply looking at the portrait, even had he known the original, would have detected any error; yet in viewing a print taken before and after the drying, there was a most marked difference in the expression. The picture was that of a child with dark eyes taken front face. In the print taken after the drying process had been performed, the eyes appeared somewhat larger and finer, than in the other, and the face had somewhat of an expression of childish astonishment about it which was far from displeasing. Indeed, we can quite understand that, as Mr. Debenham stated, the parents like the picture particularly. As a print had been taken from the negative before the drying took place, it is evident that the negative had been dried and wetted again, either to undergo clearing or some other process, before the drying which had caused the change took place ; and we may mention in this connec tion that the use of at all a strong acid bath for clearing the yellow stains from negatives pre-disposes to the effect which we have described. Mr. Debenham was fortunate in having his negative rather improved than otherwise in the special case which we have cited, but we fear that photographers must not look to the process of drying negatives at too high a tem perature as a means of obtaining flattering portraits of their customers, but that, on the contrary, we must con sider the action which we have described as one which causes distortion, and that by no means only apparent, but, on the contrary, very real. PRACTICAL NOTES ON RETOUCHING. BY W. M. ASHMAN. Ten years ago, as probably most of my readers are aware, there was a great outcry against negative retouching. Those gentlemen who as usual knew all about it, con demned the practice as being calculated to do all sorts of mischief; in a word, to be thoroughly bad. Such opinions or prognostications were freely expressed in the current literature of that time ; but by degrees these writers have been drawn into the meshes, and put as much work on their negatives as other folks do. Certainly with the advent of gelatino-bromide plates, some few made a futile attempt to abolish the art; but they will scarcely try it again. The few enemies retouching has at the present day are invari ably found among those artists who, after pencilling away at the negative for half an hour, find it looks none the better for the treatment it has received. . Among the exhibits at the Photographic Society of