"As the professional video DSLR continues to take hold of the market, the same problems have continued to exist: Foremost, many DSLRs are equipped with a non-full frame sensor (APS-C or Micro 4/3) most of these cameras are unable to shoot in a way that truly mimics Super 35mm film(full frame); Secondly, with all of these new mounts for cropped sensors, there are much fewer original lenses that are compatible with these cameras and the prices for them are much higher than most standard EF lenses. Designed for MFT Mount Cameras and Canon EF Lenses Magnification of 0.75x Increase an Additional Stop of Light, T-Stop Display 4 Element 4 Group Optical Element, Seven Layers Anti-Reflective Coatings Enhanced Performance on MTF Wireless Remote Focus and Aperture Solid Metal Build Quality, 1/4 mount Separate Extended Cable and Bracket The first solution most people think of to solve these problems is to use an adapter that allows for the use of Canon full-frame lens on cropped sensor cameras. These solutions exist, but they cause the frame of the camera to be cropped. That means what looks like a 100mm lens on a 35mm full frame sensor will actually only look like a 50mm lens on a micro 4/3 sized sensor because the micro 4/3 sized sensor, roughly 18mmx14mm, is smaller than 36 x 24 mm (35 mm) film frame. Since the sensor is smaller, the field of view captured on a cropped sensor camera is different than that of a full-fram|For Mounting Canon EF Lenses to MFT|0.75x Focal Length Reducing Optics|Wireless Control of Iris and Focus|Wireless Start/Stop of GH4 and BMPCC"