{"overview":"The Contax 140mm f\/2.8 Sonnar is a medium-telephoto Sonnar-formula lens made for the Contax system. Sitting just beyond the classic 135mm portrait length, it was intended for portraiture, candid work and short-range telephoto shooting where the Sonnar design's smooth rendering is valued.","market_narrative":"Hammer prices at UK auction are thin on the ground for this lens, with a single recorded sale at £230 in 2023 setting the only firm reference point as of today. As wholesale saleroom results (excluding buyer's and seller's commission), that figure suggests a clean copy is worth broadly in that region, though with so few data points the lens's true value and what it sells for at retail can vary noticeably with condition and completeness.","buying_guide":"Inspect the front and rear elements under a strong light for fungus, haze and cleaning marks, and check internal elements for any signs of separation showing as edge discolouration. Work the focus through its full travel to confirm it is smooth rather than stiff or sticky, and rotate the aperture ring while watching the blades for oil residue or sluggish action that would indicate a service is needed.","specs":"Specific specifications beyond the 140mm focal length and f\/2.8 maximum aperture of this Sonnar-type lens are not documented in the data provided.","faq":[{"q":"What is a Contax 140mm f\/2.8 Sonnar worth today?","a":"Based on the limited UK auction record, a clean example sold for £230 at hammer in 2023, which is the best available guide to its current price."},{"q":"How much does a Contax 140mm f\/2.8 Sonnar sell for at auction?","a":"Only one verified UK auction sale is on record, at £230 hammer, so the value of any individual copy will depend heavily on condition, glass clarity and mechanical health."},{"q":"What should I check before buying one?","a":"Look closely for fungus, haze, oil on the aperture blades, coating scratches and any element separation, and confirm the focus helicoid moves smoothly across its full range."}],"confidence":35,"reasoning":"Only a single sales record and no SPECS or variant data are provided, which limits confidence in both pricing and technical detail."}