1、​This 500mm F6.3 telephoto lens incorporates not only computer optical design, but also the latest optical multi-coating techniques. 2、​The process of multi-coating assures virtually flare-free photographs even under adverse lighting conditions resulting in crisp, high contrast pictures. 3、Fixed focus telephoto lens to use with DSLR SLR cameras. 4、Multi coated low-dispersion glass, anti-reflection coating. 5、​Telephoto lenses help catch distant landscapes and observe birds. Features: This 500mm F6.3 telephoto lens incorporates not only computer optical design, but also the latest optical multi-coating techniques. The process of multi-coating assures virtually flare-free photographs even under adverse lighting conditions resulting in crisp, high contrast pictures. Fixed focus telephoto lens to use with DSLR SLR cameras. Multi coated low-dispersion glass, anti-reflection coating. Telephoto lenses help catch distant landscapes and observe birds. Specifications: Condition: 100% Brand New Item Type: Telephoto Lens Material: Plastic + Optical Glass Color: White Angle of View: 5° Focal Length: 500mm Aperture: F6.3-22 Optical Construction: 4 Elements in 4 Groups Nearest Focus Distance: 3 meters Focus: Manual Filter Caliber: 86mm Optional Style: with T2-EOS Adapter for Canon, with T2-AI Adapter for Nikon, with T2-AF Adapter for Sony, with T2-PX Adapter for Pentax Size: Approx. 43 x 12 x 12cm / 16.9 x 4.7 x 4.7inch Weight: Approx. 1532g Package List: 1 x Telephoto Lens 1 x Adapter 1 x Storage Bag Note:Our 420-800mm zoom lens is fully manual operation, no electronic contactors, that's why your camera will not recognize the lens, it requires full manual settings on camera & lens body. If the camera model is D3400, use this lens in M mode smoothly. Here are some tips to use: 1) Set your camera to M mode with "shutter release: no lens" on(if any); 2) Adjust the lens to your desired aperature/focal length; 3) Fine tune the front focusing ring to make subject in-focus and take a sample picture. If the picture turns out dark, set the following steps: a. Lower the shutter speed, from 1/500s down to 1/100s or slower 1/50 etc; b. Raise the ISO Number, from ISO 100 to ISO 200/400/800 etc. c. Use a remote shutter release and tripod to increase image stability; d. Switch position to allow more environmental light coming through the lens into the camera imaging sensor; It might take time to get the perfect shot you want, just keep practicing and exploring the fun of manual telephoto lens.