What people are saying - Write a review
We haven't found any reviews in the usual places.
Other editions - View all
absorbed acid actinometer aperture appear Autochrome Autochrome plate bath bichromate bleached blue blue-violet bright bromide camera celluloid chrome alum coated colour filter colour photography colour plates colour-filter colour-screen coloured lights complementary colour dark developer discs Dufay dyes effect emulsion Erythrosine exposed exposure film fixed fovea front gelatine green filter grey grms Hydroquinone hypo inches intensified Kinemacolor lantern plate layer lens lines Lumiere macula method Metol microscope minutes negative object Omnicolore orange ordinary Paget panchromatic panchromatic plate paper particles pass photograph picture pigment pinatype placed positive prism produced purple red and green result retina screen seen sensitive shadow sheet silver silver bromide slide soaked solution spectrum spot squeegee stained starch grains surface theory of colour thickness thin three colours three primary colours tint transmitted transparency Uto-color varnish violet vision visual purple wash wave-length waves white light yellow Young-Helmholtz theory
Page 280 - Rodinal, 1 in 30, and development should be complete in 2 minutes. Unless a green safelight is used development must take place in total darkness. On no account should a red light or one of any colour other than the safe green be used. Development in total darkness presents no difficulty, as if the exposure given is about right, the time of development with Rodinal as given above will be correct.
Page 29 - I usually found the chloride unaltered ; sometimes, however, it had a slight yellow tint. In the red, or beyond the red, it looks a rose or lilac tint. The image of the spectrum shows beyond the red and the violet a region more or less light and uncoloured. Beyond the brown band, which was produced in the violet, the silver chloride was coloured a grey-violet for a distance of several inches. In proportion as the distance from the violet increased, the tint became lighter. Beyond the red, on the...
Page 40 - The speed of a lens is usually denoted by its f/number which is the ratio between the focal length of the lens and the diameter of its entrance pupil (see page 86).
Page 29 - Goethe in 1810. It is there stated that ' if a spectrum produced by a prism is thrown on to moist chloride of silver paper, if the printing be continued for fifteen minutes, I observe the following : In the violet the chloride is a reddish brown (sometimes more violet, sometimes more blue), and this coloration extends well beyond the limit of the violet ; in the blue the chloride takes a clear blue tint, which fades away, becoming lighter in the green. In the yellow I usually found the chloride unaltered...
Page 29 - I usually found that the chloride was intact ; sometimes, however, it had a light yellow tint ; in the red, and beyond the red it took a rose or lilac tint. " This image of the spectrum shows, beyond the red and the violet, a region more or less light and uncoloured ; this is how the decomposition of the silver chloride is seen in this region.
Page 29 - ... whilst a constant position for the spectrum is maintained by any means, I observe the following : In the violet light the chloride becomes a reddish-brown (sometimes more violet, sometimes more blue), and this colouration extends well beyond the limit of the violet. In the blue part of the spectrum the chloride takes a clear blue tint, which fades away, becoming lighter in the green. In the yellow I usually found the chloride unaltered ; sometimes, however, it had a light yellow tint. In the...
Page 280 - OF NEGATIVE. Most developers may be used, provided the resulting negative be clean and soft. The best results are obtained with Rodinal, 1 in 30, and development should be complete in 2 minutes. Unless a green safelight is used development must take place in total darkness. On no account should a red light or one of any colour other than the safe green be used. Development in total darkness presents no difficulty, as if the...
Page 280 - Rinse the plate and fix in the following bath : — Hypo . . . . . . . . . . 6 ozs. Potass, metabisulphite . . . . J oz. Water . . . . . . . . . . 20 ozs. Wash again for about 15 minutes, and put to dry. MAKING THE TRANSPARENCY. To obtain the best results the following conditions must be observed: — The transparency should be of black tone, perfectly clear, and free from fog, brilliant and full of detail. These conditions can be secured by using the special transparency plates and developer issued...
Page 30 - Abney were experimenting to increase the range of the collodion plate affected by the action of coloured lights. By bathing a plate in Eosin, Vogel found that he could extend the sensitivity of the plate from the yellow-green as far as the orange, and Abney, going a step further, extended it to the red by means of Cyanin blue.