{"title":"Shelyak FIGU Fiber Injection and Guiding Units","description":"\u003cp\u003eShelyak FIGU units are fiber injection and guiding units that sit at the telescope focus. They send the star's light into a 50 µm optical fiber while a guide camera keeps the star centered on the fiber entrance. The fiber then carries the light to a spectrograph installed away from the telescope, which keeps the instrument stable and the load on the mount light.\u003c\/p\u003e\u003cp\u003eTwo versions match the focal ratio of your telescope: the FIGU F\/6 and the FIGU F\/9.\u003c\/p\u003e","products":[{"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"},{"product_id":"shelyak-pf0018","title":"Shelyak FIGU F\/9 – 50µm Fiber Injection \u0026 Guiding Unit","description":"\u003cul class=\"DAV-feature-list\"\u003e\n\u003cli\u003eOptimized for F\/9 telescope optical systems\u003c\/li\u003e\n\u003cli\u003eInjects starlight into a 50µm core optical fiber\u003c\/li\u003e\n\u003cli\u003eIntegrated guiding port for precise target centering (camera not included)\u003c\/li\u003e\n\u003cli\u003eAccepts calibration light via a separate 200µm fiber\u003c\/li\u003e\n\u003cli\u003eRemote-controlled mirror for switching between star and calibration source\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\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\/9 – 50µm Fiber Injection \u0026amp; Guiding Unit\u003c\/h2\u003e\n\u003cp\u003eThe Shelyak FIGU (Fiber Injection and Guiding Unit) F\/9 is engineered to mount at your telescope's focus, precisely channeling starlight from an F\/9 optical system into a 50µm fiber for analysis with an eShel or Whoppshel spectrograph. It features a remote-controlled mirror to instantly switch between your target star and a calibration module's 200µm fiber, ensuring seamless and accurate data acquisition for serious spectroscopy.\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\u003ePrecision Fiber Injection for F\/9 Telescopes and 50µm Fibers\u003c\/h3\u003e\n\u003cp\u003eThe core function of the FIGU F\/9 is to solve the critical challenge of efficiently feeding a spectrograph. By matching the F\/9 light cone of your telescope to the 50µm core of the spectrograph's optical fiber, it maximizes light throughput and ensures your instrument receives the strongest possible signal, which is essential for capturing high-resolution spectra of faint targets.\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\u003eIntegrated Guiding and Calibration via a 200µm Fiber Input\u003c\/h3\u003e\n\u003cp\u003eThis unit integrates two essential functions for successful spectroscopy. A port for a guiding camera (not included) allows you to view the telescope's field, locate your target, and guide directly on the star to keep it perfectly centered on the tiny 50µm fiber entrance. For calibration, a remote-controlled internal mirror flips to accept light from a 200µm fiber connected to your calibration module, letting you record reference spectra without altering your telescope's pointing.\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\u003eFIGU F\/9 vs. F\/6: Adapting for Slower Optical Systems\u003c\/h3\u003e\n\u003cp\u003eThis F\/9 model is a specialized variant of Shelyak's F\/6 FIGU, designed specifically for telescopes with slower focal ratios like Schmidt-Cassegrains or Maksutov-Cassegrains. It includes an integrated focal reducer that converts the telescope's F\/9 beam to the optimal input ratio for the spectrograph. This ensures that users of F\/9 systems achieve the same high efficiency and spectral resolution as those with faster telescopes, without needing external optical adapters.\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 purpose of the Shelyak FIGU F\/9?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe Shelyak FIGU F\/9 is a specialized adapter that mounts at your telescope's focus. Its primary job is to take the light from a star captured by your \u003cstrong\u003eF\/9 telescope\u003c\/strong\u003e and inject it precisely into the \u003cstrong\u003e50µm optical fiber\u003c\/strong\u003e that feeds a spectrograph like the Shelyak eShel, enabling you to perform scientific spectral analysis.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eDo I need a separate guide camera for the FIGU F\/9?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes, a guiding camera is required but \u003cstrong\u003enot included\u003c\/strong\u003e. The FIGU F\/9 has a dedicated port for a guide camera, which is essential for viewing the starfield, accurately placing your target onto the fiber's entrance, and maintaining precise tracking during an exposure.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eHow do I switch between my star and my calibration lamp with the FIGU F\/9?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe FIGU F\/9 contains a \u003cstrong\u003eremote-controlled mirror\u003c\/strong\u003e inside the unit. This allows you to electronically switch the input source from the telescope's starlight to the light from your calibration module (fed via a 200µm fiber) without physically touching or disturbing the telescope setup, ensuring repeatable and accurate calibrations.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhy do I need the F\/9 version of the FIGU instead of the F\/6 version for my SCT?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eStandard Schmidt-Cassegrain Telescopes (SCTs) typically operate around f\/10, very close to F\/9. The FIGU F\/9 includes a built-in focal reducer specifically to convert this slower light cone to the optimal angle for the spectrograph's fiber. Using the F\/6 version on an F\/9 telescope would result in significant light loss and inefficient performance. The F\/9 model is purpose-built for these systems.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat spectrographs is the FIGU F\/9 – 50µm designed for?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThis unit is designed as a core component for Shelyak's own spectroscopy systems. It is the standard fiber injection unit for the \u003cstrong\u003eeShel\u003c\/strong\u003e and \u003cstrong\u003eWhoppshel\u003c\/strong\u003e spectrographs when used with an F\/9 telescope.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eHow does the FIGU F\/9 help me get an accurate spectrum of Vega (Alpha Lyrae) with my C8 at F\/9?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eFirst, you would use the guiding port on the FIGU F\/9 to view the starfield and precisely center Vega (Alpha Lyrae) on the 50µm fiber optic input. Once centered, you can begin your exposure. Before or after, you use the remote control to flip the internal mirror, allowing light from your calibration lamp to enter the spectrograph. This provides a reference spectrum, which is critical for accurately calibrating the wavelength of the data you captured from Vega.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\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":52943036219677,"sku":"SHK-PF0018","price":6168.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/files\/Shelyak-FIGU-F-9-50-m-1_0bbbc0c1-6cdd-4d37-9342-0f8e6a2df26e.jpg?v=1789616062"}],"url":"https:\/\/davidastro.com\/en-us\/collections\/shelyak-figu-fiber-injection-and-guiding-units.oembed","provider":"David Astro","version":"1.0","type":"link"}