Askar FMA135 Aperture ED Apochromat Lens Barrel 30mmF4.5

The common sense of small diameter will change! This is a palm-sized lens barrel that is ideal for television viewing. ●It is a 30mm aperture, 135mm focal length, F4.5 lens barrel that uses a 3-element objective lens and 3-element flattener, including one ED lens. It is a high-performance lens barrel that has almost no axial chromatic aberration and uses a flattener to form a flat image all the way to the periphery of the image circle. ●Image circle covers up to APS-C sensor. ●The standard mounting screw for the camera adapter is an M42 male screw. ●Back focus is 55mm. ●You can attach an American size filter in front of the objective lens using the included adapter. ●A 31.7mm eyepiece adapter is included and can also be used for visual observation. Installing a CMOS camera is also easy. ●Finder bracket included. It can also be used as a high-performance finder or guide mirror. In addition to being compatible with Vixen's finder pedestal standards, the bottom is equipped with a 1/4 inch camera screw, so it can be attached directly to a camera head.