Page:Popular Science Monthly Volume 88.djvu/745

 Popular Science Monthly

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��of taking observations is to hoist an officer to the top of an extension or telescopic mast or tower. There the view is excellent until a bullet or shell interrupts his work.

If in place of a human observer, the "eye" or semi-spherical mirror of the ob- servation apparatus were substituted the securing of necessary observations would not be as costly to life, and the view ob- tained would be a

��more extensive one.

More Motion - Pictures in Color

NATURAL- color moving- pictures have so far achieved very little success, mechanic- al difficulties being thestumblingblock which no inventors have yet been able to overcome suc- cessfully. One com- pany has developed hand-tinting to a fairly satisfactory degree, although the results have not yet attained the necessary stand- ard. The color ef- fects are somewhat obvious. Another maker of colored moving- pictures placed his on the market before be- ing commercially perfected. With this process it was

necessary to run the film through the projecting machine at twice the normal speed, natural-color results being ob- tained by a revolving color disk which allowed red and green pictures to be flashed alternately on the screen. The same process took place when the picture was taken. The latest attempts at moving-picture color photography is suggested by an English inventor who proposes to expose alternate "frames" or pictures of a film through a shutter provided with a color filter. On one "frame" the colors in the photographed

���object which contain green will be regis- tered on the next "frame;" various shades and tones of red will be separated out. When the positive film is printed from the negative strip it will be stained orange and green in alternation. Two positive films will be printed from the one negative and stained, then super- posed and cemented together. Alternate frames are stained green and orange, and the two strips

��The observer sits safely inside the hut and watches what is going on in the semi- spherical mirror on the table

��SO arranged in as- sembling that when the film is ready for projection one green frame will be opposite an or- ange frame. The film will be run through the pro- jection machine at normal speed, i. e., sixteen frames a second, and the re- sultant image on the screen, if the process works out as it is planned, will be lifelike in color. By a com- plication of the pro- cess, using three fundamental col- ors, instead of or- ange and green, fin- er gradations of color will be possi- ble. The difficul- tues which beset this plan can be removed by ade- quate mechanical means. Coloring alternate frames red and green has not yet been successfully accomplished — at least on a commercial scale — although it probably could be done. The other difficulty is to secure positive film half the present thickness which would be sufficiently flexible and durable when two strips were cemented. The matter of superposing two film sections, so that the images exactly coincide- — and this is absolutely necessary due to the immense magnification which takes place — is an important mechanical problem which must be thoroughly worked out.

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