Samyang's budget telephoto mirror alternative — the 300mm f/6.3 ED for APS-C.
Samyang (marketed as Rokinon in North America) is a South Korean optics manufacturer producing affordable manual-focus lenses for multiple camera systems. The 300mm f/6.3 ED UMC CS is a telephoto prime with Extra-low Dispersion (ED) glass and Ultra Multi Coating (UMC), designed for APS-C sensor cameras in the CS (Crop Sensor) designation.
300mm focal length, f/6.3 maximum aperture, ED glass element, UMC (Ultra Multi Coated), manual focus only, APS-C image circle (CS), Sony E mount, 62mm filter thread.
The 300mm focal length on APS-C gives approximately 450mm full-frame equivalent telephoto reach at an affordable price. Manual focus only limits use for fast-moving subjects but ED glass and UMC deliver good optical quality for static telephoto work. The compact size and light weight compared to full-frame super-telephoto lenses makes it practical for travel.
Inspect for fungus, haze, and coating condition. Test manual focus helicoid smoothness throughout the range. Confirm Sony E mount engagement. Check aperture ring function — blades should be clean and the ring should click firmly at each stop.