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Hand Cameras 162

shutter, camera, adjustments, return, various and sizes

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HAND CAMERAS 162. General Notes. Owing to the great variety of hand cameras, a detailed description of them would demand more space than is warranted by the interest of such an account, which would to a large extent be a repetition of the catalogues of makers and dealers. We shall therefore restrict ourselves to some notes on the principal types in use at the present time, and to the description of some of the essential parts.

The first thing to emphasize is that a cheap camera, if handled intelligently, can yield quite as interesting and artistic photographs as those taken with a costly instrument. The superiority of the latter lies in the fact that it permits of a larger range of subjects being tackled, and allows of exposures being made under conditions where the owner of a cheap camera would have to abstain from taking a photograph. But the beginner stands a much better chance of success with a very simple camera, one with the least number of adjustments, than with one of many movements, some of which may be overlooked and others used wrongly.

Let us, however, note that some makers have recently developed, especially in the very small sizes (3 X 4 cm. and under), various patterns embodying the automatic linkage of various components and various safety devices, leaving only a very few manipulations or adjustments to the operator, thus removing almost all possi bility of faulty manipulation. Such devices include the coupling of a range-finder with the focussing adjustment, the correction of finder parallax (§ 169), the linkage of the shutter and iris diaphragm adjustments [either checked or actually governed by a photo-electric cell (§ 326) with correction in case a light-filter carried on a swinging arm is placed before the lens], the auto matic changing of exposed film, the linkage of this changing mechanism with the setting mechanism of the shutter, the bolting of the shutter until the exposed film has been changed., the return to normal adjustments (closed shut ter if it has been left open after exposure, return of the shutter to " instantaneous - marking, return of the iris to full aperture, removal of the light-filter from the lens) by the act of closing the camera, the automatic return of the exposure counter to zero when the loading door is opened.

163. A prime consideration in the selection of cameras for use in hot and very damp climates, particularly in the tropics, is the choice of the material of which they are made.

Many modern instruments, especially of very small sizes, are built entirely of bare or lac quered non-rusting metals or alloys, or with bodies moulded in materials which, like bake lite, are not affected by the worst atmospheric conditions. Hot, damp air tends to cause leather coverings and bellows to become detached, to warp the wood (and often to separate the glued joints), and to rust all fittings of iron or ordinary steel. Attacks by insects complete the destruc tive effect of damp air on leather bellows.

Teak is one of the few woods that resist such climates. All parts must be screwed with brass screws. The wood should not have a leather covering. The shutters of the dark slides must never be of the curtain or hinged types, for the wooden strips may come unstuck. Single slides or changing boxes of almost rustless metal (special steels, nickel, German silver, aluminium) should be used exclusively. The shutter should preferably be of simple construction, without parts of iron or ordinary steel, and easy to repair in case it gets out of order.

164. Miniature Cameras. Since 1925 there has been a marked tendency to adopt smaller and smaller sizes, sometimes indeed beyond reason able bounds (a camera was built for 9 )< 12 mm. pictures on roll-film mm. wide 1). This reduc- tion in size, involving a considerable decrease in bulk and weight, has been very favourably received by amateurs and even by a fair num ber of professionals. It is indeed justified for various technical reasons.

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