0.72x Focal Reducer Speed Booster Adapter for M42 screw lens to Sony E mount APS-C – A6500 A6000 NEX-6

Introduction 0.72x optical glass lens adapter for using Sony NEX (E) mount APS-C digital cameras with M42 mount (42mm x 1.0) lenses.(Optional M39-M42 adapter ring for M39 lens) Reduces focal length to 0.72, adjust the image size to near 1:1, so that the focal length of the image is close to actual focal length of the lens, e.g. 50mm x 1.5 x 0.72 = 54mm. Helps to increase the maximum aperture to 1 stop, also can use it faster by 1 stop. Switching camera to “Release w/o lens” mode is essential.Allows focus infinity.Blue spot will occur if lens is shot to sunlight or lamp directly.With front and rear caps.