Abstract: A view camera which includes, among other components, a lens standard for containing a lensboard and lens and a film standard for receiving a film holder containing film is disclosed herein along with a reliable technique for aligning the lens and film standards such that the lens plane defined by the lens standard and the film in the film standard are in confronting, parallel relationship to one another. This is accomplished by optically utilizing a set of mirrors within the camera and indicia located on at least one of the mirrors. The latter are manipulated until the indicia takes on a specific form, as viewed from outside the camera, which form corresponds to the desired parallel relationship between the film and lens plane.

Abstract: A hermetically sealed cassette cartridge is disclosed, which encapsulates an optical disk suitable for use in an optical information recording and retrieval device. The cassette cartridge comprises a structural casing having a cavity for containing said recording medium and a spindle hub adapter for rotating the disk for data access. Data transfer is accomplished through a flexibly mounted transparent window, said window serving not only as a hermetical seal but also to alleviate the need for a thick dust defocusing layer on the said encapsulated recording medium.