Abstract: An exposure control device for use with a camera provided with two objective lenses having different focal length which are selectively used includes two exposure control elements which are disposed in front of and facing to the two objective lenses, respectively, and simultaneously driven by a drive means. One of the lights passed through the respective exposure control elements which is selected by optical path changing means is allowed to reach a film. The exposure control elements are used either diaphragms which usually allow the admittance of light into the objective lenses or shutters which are usually forced to be in positions where intercepting the optical paths of the objective lenses.

Abstract: An automatic focusing apparatus for use with a camera of the type having two interchangeable lenses with different focal lengths, includes a ranging device for finding in which distance range is located an object to be photographed, i.e., close range or long range. The ranging device is capable of shifting the position of the boundary between short range and long range when interchanging lenses in order to widen the limits of the range in which either of the lenses can be focused better.

Abstract: An exposure control device for use with a camera provided with two objective lenses having different focal lengths which are selectively used includes two exposure control elements which are disposed in front of and facing the two objective lenses, respectively, and simultaneously driven by a common drive. The light passed through the respective exposure control elements which is selected by an optical path changer is allowed to reach a film. The exposure control elements are diaphragms which allow the admission of light to the objective lenses. A pivotal arm has at least one pin at at least one end that engages in a slot in each of the diaphragms. Another end of the arm carries an armature that can be moved by at least one electromagnet and that is urged toward an intermediate position by a spring.

Abstract: A dual lens camera having a relatively long focus lens and a relatively short focus lens either one of which is selected for telephotographing and wide angle photographing is provided with a movable mirror and an exposure aperture located behind the short focus lens, and a fixed mirror located behind the long focus lens with an angle of inclination more than a right angle relative to the optical axis thereof. Upon wide angle photographing, the light passed through the short focus lens can travels straightly to the exposure aperture. When selecting the long focus lens to effecting telephotographing, the movable mirror is pivoted to position in front of the exposure aperture so as to reflect the reflected light by the fixed mirror and thereby organize a Z-shaped optical path for the long focus lens. Simultaneously, the short focus lens is shifted in the direction perpendicular to the optical axis thereof for the purpose of the pivotal movement of the movable mirror without any interference therewith.

Abstract: A camera comprising two parts, i.e., a main camera body and a movable body portion, one of which includes a film supply chamber and the other includes a film take-up chamber. The movable body portion is capable of extensibly moving to its film loading position so as to get a lengthened film passage way extending between the film supply and film take-up chambers. A container with a previously drawn film leader is inserted axially into the film supply chamber with the threading of the film leader into the film passage way. Closing a film loading door causes automatically the movable body portion to move toward and incorporate with the main camera body as a complete camera body. In the complete camera body, the film loading door is restricted to open and a motor for film advancement is actuated.

Abstract: A photographic camera having a configuration like a thin box comprises a camera body and a handle grip. When the camera is used, the camera body is rotated relative to the handle grip through an angle of about 90.degree. to be transverse to the handle grip. When not in use, the handle grip is aligned with the camera body. The handle grip is hollow to receive the camera body therein; and a support housing slidable and permanently disposed in the handle grip is rotatably secured to the camera body.

Abstract: One or more polymeric peroxides and vinyl type monomers containing vinyl type unsaturated carboxylic acid monomers are subjected to copolymerization, followed by neutralizing more than 50 mole percent of the carboxylic acid groups in the resultant product, thereby obtaining copolymers having peroxy bonds therein which are soluble in water or a mixed solution of water and anaqueous organic solvent (represented as solvent D in this disclosure). The said copolymers having peroxy bonds therein and vinyl type monomers are subjected to block-copolymerization, in the presence of solvent D, whereby the said copolymers having peroxy bonds in the molecule thereof are cleavaged at the peroxy bonds thereof, obtaining block copolymers with high efficiency.Combining order of the vinyl type monomers employed in the first copolymerization and the ones employed in the second copolymerization may be reversely employed. The neutralization of the carboxylic acid groups may be carried out after the second block copolymerization.

Abstract: An aqueous liquid dispersion of polymers can be obtained by two steps of reaction comprising the first step of copolymerizing polymeric peroxide with vinyl type monomers, whereby copolymers having peroxy bonds therein are obtained and the second step of subjecting said copolymers having peroxy bonds therein to block copolymerization with vinyl type monomers which are different in kind from the one employed in the first step of reaction, whereby said copolymers having peroxy bonds therein are cleaved at the peroxy bonds thereof, thereby obtaining block copolymers with high efficiency.

Abstract: A photographic camera is provided with a pair of data printing systems. The first data printing system is arranged to print an image of data-representing characters along one of the longer sides of the image frame of the film so that the characters are printed on the printed photo in the same orientation as the subject matter of the photo when the photo is taken with the camera body held in its normal position. The second data printing system is arranged to print an image of the data-representing characters along one of the shorter sides of the image frame so that the characters are also printed on the printed photo in the same orientation as the subject matter of the photo when the photo is taken with the camera body held sideways with the shorter sides of the image frame oriented horizontally.

Abstract: When a photographic camera is set to take a picture using a strobo, depression of a shutter release button of the camera is prevented until the charge stored in a capacitor for the strobo reaches a required level to flash a strobo discharge lamp. A shutter lock means includes a mechanical locking lever, an electromagnetic lock releasing means and a control circuit for controlling the electromagnetic lock releasing means. The mechanical locking lever is located at a lock position where it prevents depression of the shutter release button when the camera is set to take a picture using the strobo, and is held in the lock position until the electric charge stored in the capacitor reaches the required level by the attractive force of an electromagnet of the electromagnetic lock releasing means.

Abstract: An exposure control device for a photographic camera including an exposure control plate for changing an aperture size, a mark indicating plate bearing a plurality of weather marks arranged in a line movable in the direction in which the marks are lined, and a manually operable exposure control knob connected with the exposure control plate. The exposure control knob has an index to be selectively aligned with one of the weather marks. A plurality of distance marks are arranged in a line parallel to the weather marks on the mark indicating plate. The mark indicating plate is movable in a direction perpendicular to the direction in which the marks are lined so that one of the two lines of marks is selectively indicated through an indicator window.

Abstract: An accessory foot fixed to an accessory such as a strobo flash light unit has a demountable foot member in addition to a standardized foot part. The demountable foot member is removably mounted to the foot to elongate the length of the standardized foot part to be inserted into a shoe fixed to a camera body. The elongated foot is engaged with a specially designed long accessory shoe to firmly hold the accessory on the camera body. When the accessory is mounted to a camera body with an ordinary standard accessory shoe, the demountable accessory foot member is removed from the accessory so that the standardized foot part of the foot may be accommodated with the standard accessory shoe.