The Dictionary Of Photography

A True Historic Record Of The Art & Practice Of Photography 100 Years Ago.

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Film Photography
Bands of Film in the Roller Slide or Roll Holder. The roller system is by far the most popular at the present time (see Roller Slide), but as the mechanical arrangements for exposing are very obvious and simple we need not enter into particulars.
The Development^ Fixing and Drying of Films. Sometimes the cut films are so thick that they may be treated like plates, but more often the tendency of the
gelatine layer to expand produces so much curling of the film as to be incon-venient.Celluloid, ebonite, or metal rims into which the cut films can be slid for developing, fixing, or washing, are now obtainable in considerable variety from the dealers in apparatus, and when these are used all operations can be conducted as with plates. Portions of very thin film cut from bands of roll film are sometimes developed singly while held in spring frames; but a method which is often more convenient is illustrated by fig. 60. A few pieces of curtain-pole of suitable diameter, are fitted at each end with a rim expansion or distance piece ; stout india - rubber rings being convenient. The film being attached as shown by means of drawing-pins. The rollers can be kept turning in an ordinary dish con-taining the developer, after which fixing and washing may be done without re-
moving the film from the roller. There
is a great advantage in allowing roll-
Fig. 60.
films to dry while pinned on a wooden
roller as shown by fig. 60; but it is not desirable to dry them on the same rollers used for other operations. The film, if allowed to dry on the roller, with the gelatinous layer outside, gets a set or strain contrary to the usual tendency to curl.
Fig. 61 shows a convenient method of dealing with a piece of roll film of moderate length ; the clips used being then sold
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