The Stirn Vest Camera is a 19th-century German detective camera designed to be worn beneath a waistcoat, with the lens protruding through a buttonhole for concealed picture-taking. This particular variant exposed four circular images, each approximately 6.5 cm in diameter, onto a rotating dry plate. It was a novelty and surveillance instrument of the late Victorian era rather than a general-purpose camera.

Auction evidence for this exact variant is extremely thin: cameraworth.com has a single hammer result on file, a £1,200 sale from May 2005 at UK saleroom level (wholesale, before commission). With no recent data points it is not possible to give a current price range for today's market with any confidence, and what a Stirn Vest Camera is worth in 2026 will depend heavily on completeness, plate condition and provenance. Specialist photographica auctions remain the realistic venue, and values for early concealed cameras of this type can swing widely depending on condition.