Part 247

Pho`to*glyph"ic (?), a. [Photo- + Gr. &?; to engrave.] Pertaining to the art of engraving by the action of light. [Written also photoglyptic.]

Photoglyphic engraving, a process of etching on copper, steel, or zinc, by means of the action of light and certain chemicals, so that from the plate impressions may be taken. Sir D. Brewster.

Pho*tog"ly*phy (?), n. Photoglyphic engraving. See under Photoglyphic.

Pho`to*glyp"tic (?), a. Same as Photoglyphic.

Pho"to*gram (?), n. [Photo- + -gram.] A photograph. [R.]

Pho"to*graph (?), n. [Photo- + -graph.] A picture or likeness obtained by photography.

Pho"to*graph, v. t. [imp. & p. p. Photographed (?); p. pr. & vb. n. Photographing (?).] To take a picture or likeness of by means of photography; as, to photograph a view; to photograph a group.

He makes his pen drawing on white paper, and they are afterwards photographed on wood.

Hamerton.

Also used figuratively.

He is photographed on my mind.

Lady D. Hardy.

Pho"to*graph, v. i. To practice photography; to take photographs.

Pho*tog"ra*pher (?), n. One who practices, or is skilled in, photography.

{ Pho`to*graph"ic (?), Pho`to*graph"ic*al (?), } a. [Cf. F. photographique.] Of or pertaining to photography; obtained by photography; used ib photography; as a photographic picture; a photographic camera. -- Pho`to*graph"ic*al*ly, adv.

Photographic printing, the process of obtaining pictures, as on chemically prepared paper, from photographic negatives, by exposure to light.

Pho*tog"ra*phist (?), n. A photographer.

Pho*tog"ra*phom"e*ter (?), n. [Photograph + -meter.] (Photog.) An instrument for determining the sensibility of the plates employed in photographic processes to luminous rays.

Pho*tog"ra*phy (?), n. [Photo- + -graphy: cf. F. photographie.] 1. The science which relates to the action of light on sensitive bodies in the production of pictures, the fixation of images, and the like.

2. The art or process of producing pictures by this action of light.

The well-focused optical image is thrown on a surface of metal, glass, paper, or other suitable substance, coated with collodion or gelatin, and sensitized with the chlorides, bromides, or iodides of silver, or other salts sensitive to light. The exposed plate is then treated with reducing agents, as pyrogallic acid, ferrous sulphate, etc., to develop the latent image. The image is then fixed by washing off the excess of unchanged sensitive salt with sodium hyposulphite (thiosulphate) or other suitable reagents.

Pho`to*grav"ure (?), n. [F.] A photoengraving; also, the process by which such a picture is produced.

Pho`to*he"li*o*graph (?), n. [Photo- + heliograph.] (Physics) A modified kind of telescope adapted to taking photographs of the sun.

Pho`to*lith"o*graph (?), n. [Photo- + lithograph.] A lithographic picture or copy from a stone prepared by the aid of photography.

Pho`to*lith"o*graph, v. t. To produce (a picture, a copy) by the process of photolithography.

Pho`to*li*thog"ra*pher (?), n. One who practices, or one who employs, photolithography.

Pho`to*lith`o*graph"ic (?), n. Of or pertaining to photolithography; produced by photolithography.

Pho`to*li*thog"ra*phy (?), n. The art or process of producing photolithographs.