Geoptik adapter for Canon EOS lens

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In November 2009 I purchased an adapter for my Canon Eos lens. So it is possible to use my lens from the DSLR also on my other cameras. The adapter fits on Canon lens with EF bayonet and EF-S bayonet. The identifier EF-S stands for Short-Back with a shorter distance between CCD plane and back lense. This new construction is used by Canon beside the EF format since 2003 for DSLR cameras with sensors in APS-C format. The EF bayonet was first used by Canon in the year 1987 and has now totally displaced the older Canon FD bayonet. The EF bayonet is a total new construction and so not compatible with predecessor FD bayonet. It is a inside bayonet with a diameter of 54 mm and a back focus of 44 mm.

Because of the adaption from Canon EOS bayonet to T2 thread (M42x0.75mm) I can use all camera types with the Canon EOS lens. This adapter from Geoptik has an optical installation length of only 19 millimeters. The Canon back focus is 44 mm to the point of focus on the CCD plane. With additional T2 extensions the reach of the focus plane is no problem with my cameras.

The free aperture of 35 mm is enough for bigger CCD sensors too without the danger of vignetting on the image edge. Additional a ring with a inside thread of 28 x 0.75 mm can be screwed in. So filters with a size of 1.25 inch can also be used.

The Geoptik adapter has a L-shaped mount plate with one 1/4 inch photo thread and three M5 threads. So a mounting on the gear tilt head of my Manfrotto 075 tripod or on a dovetail fitting on my EQ6 mount is possible. Two additional drilled holes sideways on the up side of the adapter allows the mounting of further accessory.

The Geoptik adapter for Canon EF und EF-S lens

The Geoptik adapter with Canon EOS bayonet and T2 thread mounted on a dovetail for the parallactic mount EQ6

Video camera and CCD camera with Geoptik adapter on Canon EOS Objektiv EF-S 17-85 IS UMS

Video camera and CCD camera with Geoptik adapter on Canon EOS Objektiv EF 70-300 IS UMS