{"overview":"The Rodenstock Sironar 210mm f\/5.6 is a large format plasmat-type lens intended primarily as a standard optic for 5x4 sheet film and a moderately wide option on 5x7. It is supplied in a leaf shutter for use on monorail and field cameras, covering the typical studio, landscape and architectural work associated with the focal length.","market_narrative":"At recent UK auction, hammer prices for the 210mm Sironar have ranged from £60 to £200, with a median closer to £90 based on the limited sample of three sales between 2022 and 2025. As of 2026, this remains a wholesale, saleroom-level value — clean copies in a reliable Copal shutter tend to sell for more, while examples with shutter faults or cosmetic wear pull the price down. Buyers asking what a Sironar 210mm is worth should expect that condition and shutter accuracy, rather than cosmetic grading alone, drive where an individual lens lands in that range.","buying_guide":"Inspect the glass under a torch for fungus, haze and any sign of separation around the cemented groups, and check the front and rear coatings for cleaning scratches. Work the aperture through its full range to confirm the blades are dry and snappy with no oil migration, and fire the shutter at every marked speed — sticky slow speeds are the most common fault and a service can cost as much as a cheap lens. Confirm the retaining ring, flange and cells all match and that the lens stops down evenly.","specs":"Specifications beyond the 210mm focal length and f\/5.6 maximum aperture are not documented in the supplied data.","faq":[{"q":"What is a Rodenstock 210mm f\/5.6 Sironar worth today?","a":"Based on UK auction hammer results, recent value has sat between £60 and £200, with a median around £90 — condition of the shutter and glass is the main price driver."},{"q":"How much does a Rodenstock Sironar 210mm sell for at auction?","a":"Recorded UK hammer prices sit in a £60–£200 band across the last few years, so a working copy typically sells for somewhere in the middle of that range."},{"q":"Is the Sironar 210mm a good standard lens for 5x4?","a":"Yes — 210mm is the classic standard focal length for 5x4 large format work, and the Sironar is Rodenstock's plasmat-type design aimed squarely at that use."},{"q":"What should I check before buying one?","a":"Check for fungus, haze and separation in the glass, confirm the aperture blades are dry, and test every shutter speed — a shutter service can exceed the price of the lens itself."}],"confidence":45,"reasoning":"Only three sales records and no supplied specs or variant data, so price signal is thin and technical detail is limited to publicly known category knowledge."}