PHOTOGRAPHY IN COLOURS.

Auckland Star, Volume XXXII, Issue 47, 25 February 1901, Page 2

PHOTOGRAPHY IN COLOURS.

f Photography in natural colours by the McDonough-Joly process was recently explained at the Queen's Hall, London, on the invitation of Mr Robert Kewmun. Mr H. Snowden Ward, who described the process, said that the process required verjr little special apparatus, and introduced no methods which were not known to all photographers. In making negatives, a glass screen, ruled in alternate parallel lines of transparent red, green and blue, was placed in contact with the sensitive photographic plate, and the image from the lens fell through this coloured screen upon the sensitive plate. The coloured lines only allowed light of their own colour to pass through them, ..with the Tesult that when the photographic plate was developed it formed a negative which showed no colour, but which recorded three' different fundamental colour sensations. Krom this negative a positive transpirency ova glass mig-ht be made, which, when iixed in contact with a coloured screen similar to the one through which the negative was taken, Would mask the colour lines not. needed, and show the colours present in the original object. By another modification of the process, white paper might be ruled with the fine red, green, and violet lines, over which a print might bo made from a letterpress printing b;ock produced from the colour-re-cord negative. Or, if the ruled paper were photographically sensitised, a print might be made in the ordinary photographic way, and would show a good replica of the colours of the original object.