Orthochromatic.

Also “ortho.” Black and white photosensitive material which responds to blue and green light but which does not respond to red light.

This property is useful for photographic paper used in darkrooms, as it means you can illuminate the room with light from a red or red-orange safelight and still see what you’re doing.

Orthochromatic black and white film is available, though it isn’t as common as it once was. The later technological development known as panchromatic film is most common today.

cf. black and white, panchromatic, photosensitive.

Entry last updated 2002-04-03. Term 869 of 1487.

Previous term: ortho.

Next term: OTF.

 

This document is copyright © 2002-2008 NK Guy, PhotoNotes.org. This information is provided with neither warranties nor claims of accuracy or completeness of any sort. Use this information at your own risk. All trademarks mentioned herein belong to their respective owners.

You may copy and print this document for your own personal use. You may not, however, reprint or republish this work, in whole or in part, without prior permission from me, the author. Such republication includes inclusion of this work in other Web sites, Web pages, FTP archives, books, magazines or other periodicals, CD-ROM and DVD-ROM compilations or any other form of publication or distribution. Please do not frame this site within another.

Please send comments or error reports using the feedback form.