Dallmeyer (J.H.) Oscillograph · 51mm f/1.9

{"overview":"The Dallmeyer 51mm f\/1.9 Oscillograph is a specialist fast prime from the long-established London optical maker J.H. Dallmeyer, built for recording cathode-ray oscillograph traces onto film. Its wide f\/1.9 aperture was designed to capture faint, fast-moving phosphor images rather than for general photography, and the lens is typically encountered in industrial or laboratory-style barrel form.","market_narrative":"At UK auction the 51mm f\/1.9 Oscillograph has shown a wide spread of hammer results, ranging from £200 up to £2,000, with the bulk of recent 2024 sales clustering between £850 and £1,625 and a median close to £1,237. As of 2026 these wholesale saleroom figures reflect what clean, complete examples sell for before buyer's premium, and condition, completeness of mount hardware and glass clarity appear to drive most of the variance in what the lens is worth.","buying_guide":"Inspect the elements carefully for fungus, haze and cleaning marks, as specialist industrial optics often sat unused in humid labs for decades. Check the aperture blades for oil and sluggish action, look for separation or cement yellowing between cemented groups, and confirm the focus or mounting collar turns smoothly; because this lens was made for oscillograph rigs rather than a standard camera mount, verify that any adapter or flange supplied is correct and undamaged.","specs":"Key published specifications are limited to a 51mm focal length and an f\/1.9 maximum aperture, with the lens identified by Dallmeyer as an Oscillograph objective.","faq":[{"q":"What is a Dallmeyer 51mm f\/1.9 Oscillograph worth today?","a":"Recent UK auction hammer prices have ranged from £200 to £2,000, with most 2024 results falling between £850 and £1,625 depending on condition and completeness."},{"q":"How much does a Dallmeyer 51mm f\/1.9 Oscillograph sell for at auction?","a":"Clean examples have sold for around £850–£1,625 at recent UK sales, while a rougher copy sold for £200 and an exceptional result reached £2,000 back in 2015."},{"q":"Why does the price and value vary so much between copies?","a":"Because this is a specialist industrial lens rather than a camera lens, value swings sharply with glass clarity, smoothness of the iris and focus, and whether the original mount or flange is present."},{"q":"Is the Dallmeyer Oscillograph usable on a normal camera?","a":"It was designed for oscillograph recording rigs, so using it on a stills camera requires a custom adapter, and buyers should confirm mount details before bidding."}],"confidence":45,"reasoning":"Only four sales records are available and SPECS\/variants\/facts are empty, so confidence is capped at 50 per the rules."}