Sunday, July 13, 2008

EX CATHEDRA: Cheaper Plates; Supplementary Flashlight; Packing Negatives; Field-Camera and Cycle.

Cheaper Plates.

        It is announced that the prices of dry plates have been reduced as from March 11th last. The reduction brings quarter-plates to 3/- per dozen, half-plates to 6/6, and whole-plates to 12 3. Taking the quarter-plate as the basis of comparison it will thus be seen that the reduction to 3/- - from 3/8, which was the figure reached at the last rise on August 1st, 1918, amounts to a fraction over 19 per cent. The present price of the quarter-plate, in comparison with the pro- war figure of 1/3 per dozen, is still 140 per cent, higher. The schedules issued by the
Plate-makers give the complete figures of prices for extra rapid and ordinary plates, panchromatic and X-ray plates in both the English and metric sizes.

Supplementary Flashlight.

        Photographers as a whole are not fully aware of the advantages that flashlight has to offer as a supplementary illuminant when making exposures under difficult conditions. It sometimes happens that a certain amount of day or artificial light is available by which the exposure has to be made that is, in. sufficient of itself to light certain portions of the subject sufficiently for them to be fully exposed before the more brilliantly illuminated parts were hopelessly over-exposed. It is under conditions like these that the flash-lamp, which need only be of a simple form, or which may even be dispensed with if the prepared powder, such as Johnson, is employed, becomes of real assistance in solving the difficulty. We may, in explanation, cite an instance of this which occurred in our own work some years ago. The subject was an interior of an ancient abbey, the building badly lit through stained glass windows, two of which were directly facing the camera. The details of these windows, which were, of course, fairly well illuminated, were required in the negative together with a good rendering of some dark oak choir stalls in the foreground which were very badly illuminated indeed. A plate was exposed by meter for the windows, and just before this period was complete a strong flash was fired, sufficient to illuminate the whole of the interior. Careful development produced a negative that was "just right" for its purpose. The flash should be fired almost at the end of the exposure; if this is done before, there is a tendency for the smoke from the flash to cause a belt over the picture. The above indicates some simple means of overcoming difficulties due to bed illumination, and may be noted by commercial photographers who often are expected to produce first-class results under very unfavorable conditions of lighting. Some may be inclined to adopt the usual reflector and diffuser in connection with the flash, but though this may at times be desirable when dealing with very irregular lightings, we prefer to increase the flash in strength and keep further away from the subject if the building will admit.

Packing Negatives.

        Even in such simple matters as sending a negative through the post there are pitfalls for the unwary of which anyone to whom negatives come is being constantly reminded by the receipt of parcels of glass shattered to atoms by the thump of the post office stamp. Enlarging firms who would caution their customers ought to arrange for them to visit the sorting floors of a big postal depot. It would provide salutary warning against packing negatives between pieces of card or with no greater protection than the cardboard plate box in which they travel at the risk of their lives. Now that so many pursue the photographic process no further than the making of the negative the safe transit of the developed plates to the enlarger is as important an item of after-treatment as intensification, yet many people seem not to know that to make perfectly sure of its safe arrival the negative should travel in a wooden box so that the walls keep the shock of the defacing stamp off it. If it be prevented from shaking about in the box by cotton wool, wood shavings, or even crumpled paper above and below, the sender may challenge the Nasmyths of St. Martin's-le-Grand to do their worst. One other little precaution should be noted. If several negatives of different sizes are being sent together they should be placed so as to prevent the smaller bearing unevenly on the larger. For example, a quarter-plate should not be sandwiched between two half-plates, but be laid upon them with a piece of card between.

Field-Camera and Cycle.

        Those photographers who reside in country districts and have occasionally to carry a heavy field camera and tripod upon a cycle realize that if care is not taken such means of transit are likely to have a very detrimental effect upon their apparatus. The best place for the camera case is without doubt upon a strong back carrier firmly secured to the machine, though some workers have a preference for the front carrier. In the latter position there is a greater tendency for the camera to be shaken about, while if a proper carrier is not used there is a certain strain upon the aides in guiding the machine, especially if the instrument is a heavy one. Even on a back carrier there is a tendency for the case to get badly rubbed, and even the instrument itself may be scratched if a little care is not taken as a preventive. Some time ago, after a cycle journey of some miles across badly made roads, we had the experience of a camera case rubbed right through by the vibration between it and the cycle carrier, together with a broken plate in the dark slide, which necessitated a further journey for the purpose of making another exposure. Since then we have prevented such trouble ever recurring, very simply, in the following manner. A couple of strips of felt about two inches m width and about an inch in thickness, such as may be bought for a few pence at any saddler's, is placed the bottom of the camera case for the instrument itself slides to rest upon, and another strip of felt is I upon the carrier before the case is put on. The felt will absorb some vibration, and the troubles detailed above will not be encountered. We have also adopted this idea when traveling on a motor cycle, when is equally successful. The best place for the tripod is across the handle bars or along the top tube of the cycle. Such a plan is far better than slinging the case upon the operator s back when, if the instrument is a heavy one, its weight is soon felt.

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