{"overview":"The Zeiss Ikon 18mm f\/4 Distagon is an ultra-wide-angle prime lens built around Zeiss's Distagon retrofocus optical concept, which gives the rear element enough back-focus clearance to work behind an SLR reflex mirror. At 18mm with an f\/4 maximum aperture, it sits at the wider end of the Zeiss prime range and was aimed at architectural, interior and landscape photographers who needed coverage beyond standard 24mm and 28mm focal lengths.","market_narrative":"UK auction data for this lens is thin: only a single hammer result is on record, with one example fetching £500 at a UK saleroom in March 2023. With one data point that price should be treated as indicative rather than a true market median, and what a Zeiss Ikon 18mm f\/4 Distagon is worth today in 2026 will hinge heavily on glass condition, mount demand and how clean the helicoid runs — clean, fault-free copies sell for more, while hazy or fungused examples can sell for considerably less.","buying_guide":"Inspect the front and rear elements under a torch for fungus, haze and cleaning marks, as ultra-wide elements sit exposed and often pick up coating scratches over decades of use. Check the aperture blades for oil contamination and that they snap cleanly between stops, and rotate the focus ring through full travel to feel for stiff, dry or sticky grease in the helicoid. Finally, look at cemented groups for the rainbow-edged ring that signals early lens separation, and verify the mount, rear baffle and filter thread are undamaged.","faq":[{"q":"What is a Zeiss Ikon 18mm f\/4 Distagon worth at UK auction?","a":"On the limited record available, one example hammered at £500 at a UK auction in March 2023, exclusive of buyer's premium. With only a single sale logged, this is best read as a reference point rather than a firm market value."},{"q":"How much does a Zeiss Ikon 18mm f\/4 Distagon sell for compared to retail asking prices?","a":"The £500 figure on record is a UK auction hammer result — wholesale saleroom level, not a dealer or retail price. Dealer asking prices for clean, serviced copies typically sit higher than auction hammer levels once commission, warranty and servicing are factored in."},{"q":"What most affects the price of this lens on the used market?","a":"Glass condition is the single biggest driver of value: fungus, haze, separation and heavy coating wear all push prices down sharply, while a clean optical path with smooth focus and clean aperture blades commands the strongest results."}],"confidence":30,"reasoning":"Only one verified sale on record and no SPECS, variants or facts supplied, so market and technical claims are deliberately limited."}