Abstract: An exposure control mechanism for use with chemical flash illumination includes a shutter having a primary shutter blade mounted for pivotal movement between a rest position wherein the shutter blade covers an exposure aperture, through an intermediate position wherein the shutter blade uncovers the exposure aperture, and a rebound position. A spring urges the shutter blade toward the rest position. A shutter driver drives the primary shutter blade from the rest position to the rebound position, and a flash firing mechanism synchronized with the shutter driver ignites a chemical flashlamp substantially simultaneously with the start of movement of the primary shutter blade.

Abstract: a photographic element is disclosed which includes a support having as a coating thereon a radiation-sensitive layer capable of selectively releasing protons in exposed areas. In direct contact with the radiation-sensitive layer is an image-forming dye capable of shifting between a mobile and an immobile form in an aqueous medium upon protonation of a carboxy or amine substituent. The portion of the dye remaining mobile after imagewise protonation can be transferred to a receiver sheet to form a viewable dye image.

Abstract: An exposure control mechanism for use with chemical flash illumination includes a shutter having a primary shutter blade mounted for pivotal movement between a rest position wherein the shutter blade covers an exposure aperture, through an intermediate position wherein the shutter blade uncovers the exposure aperture, and a rebound position. A spring urges the shutter blade toward the rest position. A shutter driver drives the primary shutter blade from the rest position to the rebound position, and a flash firing mechanism synchronized with the shutter driver ignites a chemical flashlamp substantially simultaneously with the start of movement of the primary shutter blade.