{"product_id":"shelyak-pf0008","title":"Shelyak FIGU F\/6 – 50µm Fiber Injection and Guiding Unit","description":"\u003cul class=\"DAV-feature-list\"\u003e\n\u003cli\u003eeShel Spectrograph Interface: Mounts at the telescope focus to feed starlight into the required optical fiber for Shelyak eShel and Whoppshel systems.\u003c\/li\u003e\n\u003cli\u003eIntegrated Guiding Port: Allows a user-supplied guide camera to view the field of view for precise target acquisition and on-axis guiding.\u003c\/li\u003e\n\u003cli\u003eSystem-Matched Design: Engineered to work with the specific focal ratios common to telescopes used for high-resolution spectroscopy.\u003c\/li\u003e\n\u003cli\u003eDual-Source Input: A remote-controlled mirror switches between the target starlight and an external calibration light source.\u003c\/li\u003e\n\u003cli\u003eDedicated Calibration Fiber Port: Accepts a secondary fiber from a calibration unit for acquiring essential reference frames.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c!-- more --\u003e\n\u003cul class=\"tabs\"\u003e\n\u003cli class=\"active\"\u003eDescription\u003c\/li\u003e\n\u003cli\u003eFAQ\u003c\/li\u003e\n\n\u003cli\u003eDownloads\u003c\/li\u003e\n\u003cli\u003eWarranty\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cul class=\"tabs-content\"\u003e\n\u003cli class=\"active\"\u003e\n\u003cdiv\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section-center\"\u003e\n\u003ch2\u003eShelyak FIGU F\/6 – 50µm Fiber Injection and Guiding Unit\u003c\/h2\u003e\n\u003cp\u003eThe Shelyak FIGU (Fiber Injection and Guiding Unit) is the critical interface between your telescope and an eShel or Whoppshel spectrograph. It mounts at the telescope's focus to precisely inject starlight into the instrument's small-diameter optical fiber. This unit integrates on-axis guiding and remote source selection, forming the heart of your spectroscopic data acquisition system.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003ePrecise Fiber Injection for Shelyak eShel Spectrographs\u003c\/h3\u003e\n\u003cp\u003eThis unit is engineered for specific telescope focal ratios to ensure optimal light coupling into the small-diameter optical fiber required by Shelyak echelle spectrographs. To achieve and maintain this critical alignment, the FIGU incorporates a port for a guiding camera (not included). This allows you to view the starfield directly, center your target perfectly on the fiber's microscopic entrance, and maintain accurate tracking throughout the exposure for maximum signal-to-noise ratio.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eRemote Mirror for Starlight and Calibration Switching\u003c\/h3\u003e\n\u003cp\u003eThe FIGU includes a remote-controlled internal mirror that enables instantaneous switching between two light sources. In one position, it directs starlight from the telescope into the science fiber. In the other, it accepts light from a calibration module via a separate, larger-diameter optical fiber. This function is essential for capturing reference spectra like flats or arcs without altering the telescope's position or the instrument setup.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat is the main purpose of the Shelyak FIGU F\/6 – 50µm?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eIts primary role is to act as an interface at the telescope's focus, precisely injecting the light from a star into the optical fiber of an eShel or Whoppshel spectrograph while also allowing for guiding.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat else do I need to use the Shelyak FIGU?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYou will need a compatible telescope with the correct focal ratio, a Shelyak eShel or Whoppshel spectrograph, a guiding camera, and a calibration module with its own optical fiber. These items are not included.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eHow does the Shelyak FIGU help with guiding on a target star like Deneb (Alpha Cygni)?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe FIGU has a port for a guide camera that sees the area around the fiber entrance. You can place Deneb directly on the fiber, and then use the guide camera to keep it perfectly centered during long exposures, preventing signal loss from atmospheric turbulence or tracking errors.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eHow does the remote-controlled mirror on the FIGU work?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe internal mirror can be electronically flipped between two positions. One position directs the light from the telescope to the spectrograph's fiber. The other position blocks the starlight and instead directs light from a separate calibration fiber into the spectrograph, allowing you to take calibration frames.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eCan I use the Shelyak FIGU with any telescope?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eNo, this FIGU model is specifically designed for telescopes operating at a particular focal ratio to ensure the light cone correctly matches the acceptance angle of the optical fiber. Using it with significantly faster or slower telescopes will result in inefficient light injection.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhy is switching to a calibration source important for spectroscopy with the FIGU and an eShel?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eHigh-resolution spectroscopy requires calibration frames (like Thorium-Argon lamps) to accurately wavelength-calibrate the science data. The FIGU's remote switching lets you capture these calibration frames immediately before or after your science exposure without touching the setup, ensuring the highest possible accuracy.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\n\u003cli\u003e\n\u003cul class=\"DAV-grid\"\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\u003ca href=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/files\/Shelyak_eShel_Installation_and_Maintenance_Manual.pdf\" target=\"_blank\"\u003e\u003csvg class=\"DAV-img-box\" viewbox=\"0 0 512 512\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\"\u003e\u003cpath d=\"M0 64C0 28.7 28.7 0 64 0L224 0l0 128c0 17.7 14.3 32 32 32l128 0 0 144-208 0c-35.3 0-64 28.7-64 64l0 144-48 0c-35.3 0-64-28.7-64-64L0 64zm384 64l-128 0L256 0 384 128zM176 352l32 0c30.9 0 56 25.1 56 56s-25.1 56-56 56l-16 0 0 32c0 8.8-7.2 16-16 16s-16-7.2-16-16l0-48 0-80c0-8.8 7.2-16 16-16zm32 80c13.3 0 24-10.7 24-24s-10.7-24-24-24l-16 0 0 48 16 0zm96-80l32 0c26.5 0 48 21.5 48 48l0 64c0 26.5-21.5 48-48 48l-32 0c-8.8 0-16-7.2-16-16l0-128c0-8.8 7.2-16 16-16zm32 128c8.8 0 16-7.2 16-16l0-64c0-8.8-7.2-16-16-16l-16 0 0 96 16 0zm80-112c0-8.8 7.2-16 16-16l48 0c8.8 0 16 7.2 16 16s-7.2 16-16 16l-32 0 0 32 32 0c8.8 0 16 7.2 16 16s-7.2 16-16 16l-32 0 0 48c0 8.8-7.2 16-16 16s-16-7.2-16-16l0-64 0-64z\" fill=\"#0047a7\"\u003e\u003c\/path\u003e\u003c\/svg\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eShelyak eShel Installation and Maintenance Manual\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/a\u003e\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003ca href=\"https:\/\/davidastro.com\/pages\/shelyak-warranty-policy\" rel=\"noopener\" target=\"_blank\"\u003eShelyak 1-Year Warranty\u003c\/a\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"Shelyak","offers":[{"title":"Default Title","offer_id":52943034843421,"sku":"SHK-PF0008","price":4959.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/files\/Shelyak-FIGU-F-6-50-m-1_a71ab7fe-6e99-42cb-aa9d-6aa919ad831c.jpg?v=1789616037","url":"https:\/\/davidastro.com\/fr\/products\/shelyak-pf0008","provider":"David Astro","version":"1.0","type":"link"}