Signal Lenses are very rare collectables in Horizon Forbidden West that you can find at the tops of Signal Towers, and that will be stored in the Special Gear section of your inventory. There are six Signal Towers, each with a unique Signal Lens. The only use for Signal Lenses is trading them with Raynah, an Oseram salvager who’s intent on “liberating” all of the lenses herself until she gets injured and asks you to find them on her behalf.
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To meet Raynah for the first time, start the Signals of the Sun errand quest by talking to Maleev, just outside Barren Light to the north of the settlement. You’ll meet Raynah further up the mountainside after killing some machines and, if you already have some Signal Lenses, you can trade them with her here. Once you’ve retrieved the Lens of Evening from the nearby Signal Tower and give it to Raynah, the Signals of the Sun errand will be complete, and Raynah will relocate to Barren Light. When you want to trade in more Signal Lenses, find her among a lot of tents, just south of the campfire in Barren Light. She’s marked on the map with a Signal Tower icon.
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