No.24: See Through - Fresnel Lens

Visible from a distance of over 20 miles it was used in the Old Point Loma Lighthouse in the 1850's
It measures 5' 2" (1,58m) in height and weighs 1,985lbs. (900kg) and was made in France by the firm Henry-Lepaute with several hundred hand ground crystal prisms.
Original cost was $3,810 which included the lens with three lamps, brass frame, lantern and spare parts.


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Technical info for the challenge: manual mode, 1/160s @ f/4.0 at 21.0mm, iso200, auto focus, single point metering, auto white balance, handheld leaning against glass case, processed in HDR Efex Pro2, Photoshop CS5 and Lightroom 5