We use Optical Character Recognition (OCR) during our scanning and processing workflow to make the content of each page searchable. You can view the automatically generated text below as well as copy and paste individual pieces of text to quote in your own work.
Text recognition is never 100% accurate. Many parts of the scanned page may not be reflected in the OCR text output, including: images, page layout, certain fonts or handwriting.
The Optical Magic Lantern Journal and Photographic Enlarger.
123
paper in shop windows, and also ranged in a row close to the window-pane with dark objects
behind, or else in front of a strip of mirror
placed at anything but the correct angle for
passers-by to see. Again, we have seen the Same dozen or more slides doing duty in a window for several months at a time, it
evidently being thought quite unnecessary that ;
a change would be.of any advantage.
Those who would wish to have a little extra shop window attraction by way of displaying slides for the season now at hand might do worse than resort to something of the following style. The appliance can hold any number of slides according to the diameter of the wheel portion, but in the diagram herewith, it is for holding a dozen. The slides can be changed readily, hence, little time would be expended in making a complete change at least once a day.
The relative portions of the sketch being to scale, particulars as to the making of the revolving wheel need not be entered into, as any mechanic could grasp the whole idea at a glance. The edge of the wheel should, of course, be placed facing the window, and a band on the pulley wheel (a) attached toa clockwork or electric motor would supply all the driving power necessary.
In order to get good illumination on the slides it will be necessary to have a piece of white cardboard or opal glass (B) hung on the
axle, the lower side being the heavier, so that although the wheel revolves it will remain stationary.
Various devices may be resorted to for hanging the slides on the cross rods, but perhaps the method shown at (c) will prove as simple as any, and consists of small’ springs which grip the slide at both sides.
By the judicious arrangement of shielded lights placed at side of reflector, a pretty effect is produced as each slide is gradually brought to view.
Stereoscopic Effects on the Lantern Screen.
WHAT HAS BEEN DONE AND WHAT MAY BE DONE.—No. IV.
By Txomas Bouas, F.C.S., F.I.C.
(Continued from page 118.)
FURTHER development of the
principle of the anaglyph, whereby
stereoscopic effects in colour may
be obtained, and a method appli
cable to lantern projection, has been
recently described by M. Ducos du Hauron (Revue Swisse de Photographie, Nov. 1895, p. 394), and a shorter account is to be found on p. 111 of The Amateur Photographer for February 7th, 1896. The principle of the method consists in making two of the coloured elements of the three-colour set correspond to one of the pictures of the stereoscopic pair, and making the third element of the three-colour set to correspond to the other picture of the stereoscopic pair. The sense of relief in this case is produced by the difference in drawing between one element of the threecolour set and the other two elements. In either of the above-mentioned places will befound a statement as to the three possible ways of