Shutter Dissolve for Motion Picture Cameras developed by J.E. Leonard in 1919

Leonard was the first to develop what would be the core of the Mitchell camera, the planetary gear-driven variable shutter. Mitchell later bought Leonard's patent.

Finder Shifting Mechanism for Focusing developed by J.E. Leonard in 1919

Leonard's revolutionary new rack over concept which allowed focusing directly through the taking lens without moving the lens turret (as needed in the B&H 2709.

Adjustable Curtain for Cameras developed by J.E. Leonard in 1921

Leonard continues to pioneer his camera design with adjustbale mats that allowed camera effects inside the camera. This feature would be included in all future Mitchell Cameras.

Film Moving Mechanism developed by J.E. Leonard in 1921

Leonard targets the film path which produces a steady image but would pale in comparison to Mitchell's future design. This was known as the "Clatter" movement or Type AA.

Focusing Instrument For Cameras and the Like developed by G.A. Mitchell in 1927

Now we see George Mitchell taking the lead and submitting his own patents. Here he perfects the viewfinder with the ability to magnify the image for more precise focusing.

Viewing Device for Cameras developed by G.A. Mitchell in 1927

Turning to outside the camera, Mitchell designs the most popular external viewfinder in history. Many manufacturers would buy these from Mitchell to use with their own models.

View Finder Mounting for Cameras developed by G.A. Mitchell in 1931

Ingenious method to swing the view finder out of the way but return it without loss of focus. He references his previous design of 1927 and that it has been improved upon.

Dissolving Shutter developed by G.A. Mitchell in 1931

Here, Mitchell improves upon J.E. Leonard's design of 1919 which he had previously purchased but he now uses two 180 degree semi-circular leaves.

Film Movement developed by G.A. Mitchell in 1932

A huge leap in rock steady movements which he describes as quiet in operation that has a fast pull down claw and a long period of "dwell". Known as the AB movement.

Adjustable Mat for Optical Instruments developed by G.W. Jonson in 1933

His staff improves upon previous viewfinder adjustable focal length designs with a greater preview area outside the mats and all mats are internal vs. dropped in from the outside.

Camera Focusing Mechanism developed by G. A. Mitchell in 1933

Improved method to focus the lens from the rear of the camera and geared down to provide a long range of movement.

Film movement developed by G. A. Mitchell in 1932

His ground breaking and greatest achievement of his career: the NC Camera movement using eccentrics and sliding surfaces for a noiseless operation.

Film Movement Mechanism developed by G. A. Mitchell in 1933

Improvement on the NC camera movement to perfect its design. He changes the second eccentric and reduces the total throw and reduces sawing.

Camera focusing Mechanism developed by G. A. Mitchell in 1934

This invention targets models with a lens turret and allows compensating focusing adjustments.

Finder Swinging Mounting developed by G. A. Mitchell in 1935

A uniquely designed bracket and dovetail design allows the standard Mitchell external viewfinder to swung out for door access and then swing back without loss of focus.

Mat Box Mounting for Motion Picture Cameras developed by G. A. Mitchell in 1935

Allows the mat box to quickly moved to the inoperative position for easy adjustments. First introduced on the new BNC studio model.

View Finder Parallax and Focusing Mechanism developed by G. A. Mitchell in 1935

A series of cams allows the quick selection of the appropriate lens focal length and results in the parallax corrections. Unique downward view of the Mitchell View Finder.

Operating Means for Four-Way View Finder Mats developed by G. A. Mitchell in 1936

Single knob operates interconnecting opposing mats and a calibration scale allows a quick reference. Very detailed internal construction graphic views.

Shutter Dissolve Mechanism developed by G. A. Mitchell in 1937

Improved feature introduced on the Studio BNC model which eliminated shutter creep on the dual shutter dissolve mechanism and provided a automatic lock.

Adjustable Four way View Framing Device developed by G. A. Mitchell in 1937

Continued improvements with internal mats using an extremely simple and inexpense construction. Excellent exploded cross section of the Mitchell View Finder.

Shutter Dissolve Mechanism developed by G. A. Mitchell in 1937

Mitchell references his previous Shutter Dissolve patent in 1937 but this one features the external controls used to operate the dissolve through the BNC Blimp.

Sound Insulated Motion Picture Camera developed by G. A. Mitchell in 1937

This is the main patent that detailed the famous BNC Blimp with the ground breaking sound insulation qualities and the easy of use to control all features from the outside.

Intermittent Film Movement Mechanism developed by G. H. Worrall in 1941

Improvement on the Mitchell movement that space the bearing bushing inward from the pilot pin studs to reduce emulsion debris produced by the sawing actions of the pilot pins.

High Speed Film Movement Mechanism developed by G. H. Worrall in 1942

Using previous Mitchell patents, Worrall uses a single driving cam of the circular triangle type but reverses the relations of the film pull down stroke of the previous design.

Intermittent Movement with Improved Claw Action developed by G. A. Mitchell in 1951

Improvements in the intermittant movement's engagement claw to make it more positive and smooth with the virtual elimination of the sawing action.

Intermittent Movement, Improved Lubricating developed by V. J. Evraets in 1952

Provided an oil seal of novel construction between the claw arm and can be retro fitted to any mechanism having a film movement mechanism.

Camera Viewfinder developed by G. A. Mitchell in 1966

As the BNCR was introduced, Mitchell offered 3 different reflex systems. This patent uses a spinning mirrored surface and prevents film fogging.