Photography – With exposure objective focusing means – focusing aid – or... – Mechanical rangefinder
Reexamination Certificate
2003-06-09
2004-08-17
Perkey, W. B. (Department: 2851)
Photography
With exposure objective focusing means, focusing aid, or...
Mechanical rangefinder
C396S145000, C396S360000, C396S446000, C396S536000, C396S541000, C396S349000
Reexamination Certificate
active
06778772
ABSTRACT:
FIELD OF THE INVENTION
The invention relates to a method of making an interface for changing the film format of cameras and the modification of a 3¼″×4¼″ format camera into a 4″×5″ format camera utilizing such interface. In particular, the interface is a modification of a Polaroid CB 103 film magazine, which is designed for 3¼″×4¼″ film format, to accept films in the 4″×5″ film format.
BACKGROUND OF THE INVENTION
Different film formats exist for still photography to accommodate the needs and demands in the art of still photography. The most common small film format is the 35 mm used in common point and shoot camera. The medium film format is between 35 mm and 6 cm in height, which includes 6 cm×9cm and ¼″×4¼″, which is commonly referred to as 3¼×4¼. The large film format is greater than 6 cm in height, which includes 4″×5″, commonly referred to as 4×5, and 8″×10″, commonly referred to as 8×10.
Larger film sizes provide better quality and more detail images. The largest practical format for a production hand held camera is the 4×5 format because of the limitation on the portability and maneuverability of the camera. An 8×10 format camera is heavy and cannot be used as a hand held camera.
All 4×5 camera in the marketplace have either a double window rangefinder that has one viewfinder window for framing the photograph and one rangefinder window for focusing or only has a rangefinder without parallax. Single window rangefinder/coupled rangefinder parallax combination camera exists for the 3¼×4¼ format, but not for the 4×5 format because of the tighter tolerances required for the 4×5 format camera and the need for highly skilled workers in the manufacturing process, making it economically impractical to manufacture. A couple rangefinder/parallax combination camera provides the focusing system and crop lines which permit accurate composition via the rangefinder, i.e. can adjust the crop lines in the viewfinder when adjusting the focus on the subject to take a picture. Therefore, it is easier to adjust rangefinder and cropping frame because it uses only a single window rangefinder that includes both the parallax and the rangefinder.
Therefore, there is a need for a lightweight 4×5 camera having a single window rangefinder/coupled rangefinder parallax combination.
SUMMARY OF THE INVENTION
The invention provides a method of making an interface and single window rangefinder 4×5 camera by converting existing products designed for the 3¼×4¼ format.
One aspect of the invention is the modification of a film magazine processing back designed for the 3¼×4¼ format produced by Polaroid Corporation of Cambridge, Mass. called the Model CB 103 camera back for pack films, into a CB 103 interface that may be adapted to accept different format films, including the 4×5 format.
Another aspect of the invention is the modification/combination of Polaroid's cameras that accept series 40 roll film (which is out of production and was in the 3 ¼×4¼ format) and did not allow the use of conventional wet film holder, such as Model 110/110A/110B/120/900/150, to a single window rangefinder 4×5 camera with the CB 103 interface.
A further aspect of the invention is the necessary improvements of the modified Polaroid Models 110/110A/110B/120/900/150 camera to allow it to become an operable coupled parallax/rangefinder 4×5 camera.
The CB 103 interface of the present invention comprises a frame that acts as a spacer for interconnecting two photographic components, such as a 4×5 format film and a camera that accepts the 3¼×4¼ format film magazine.
The single window rangefinder 4×5 camera of the present invention modifies the Polaroid Models 110/110A/110B/120/900/150 camera and utilizes the CB-103 interface to convert a 3¼×4¼ camera into a 4×5 camera with a coupled rangefinder/parallax combination that allows sequence shots taken at a higher speed than ever before possible for a 4×5 format, at about 1 shot/sec, and allows increased concentration on artistic aspect of picture taking and the ability to capture snap shots with spontaneity without asking the subject to wait until the camera is being readied. Additionally, the modified single window rangefinder 4×5 camera of the present invention provides a proper turn knob focusing system for accuracy and improved tolerances for a 4×5 format.
REFERENCES:
patent: 3266396 (1966-08-01), Padelt
patent: 3491671 (1970-01-01), Engledrum
patent: 4648696 (1987-03-01), Park et al.
patent: 6608971 (2003-08-01), Litman
Esq. Gloria Tsui-Yip
Miskin, Esq. Howard C.
Perkey W. B.
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