{"product_id":"zwo-electronic-filter-wheel-efw-7x50-26-7-x-50mm-square","title":"ZWO Electronic Filter Wheel EFW Gen2 - 7 x 50mm Square","description":"\u003cul class=\"DAV-feature-list\"\u003e\n\u003cli\u003eHolds 7 individual 50mm square filters\u003c\/li\u003e\n\u003cli\u003eDesigned for large format monochrome cameras like the ASI461MM Pro\u003c\/li\u003e\n\u003cli\u003eAdds only 16mm of optical path length to the imaging train\u003c\/li\u003e\n\u003cli\u003eUpward-facing USB Type-C port\u003c\/li\u003e\n\u003cli\u003eDirectly bolts to the ZWO OAG-L-68 large off-axis guider\u003c\/li\u003e\n\u003cli\u003ePowered and controlled through a single USB connection\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\u003eSpecifications\u003c\/li\u003e\n\u003cli\u003eIn the Box\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\u003eZWO Electronic Filter Wheel EFW-7x50-26 - 7 x 50mm Square\u003c\/h2\u003e\n\u003cp\u003eThe ZWO Electronic Filter Wheel EFW-7x50-26 is engineered to automate filter changes for large-format imaging, holding 7 different 50mm square filters in a rigid, CNC-machined aluminum body. It adds a minimal 16mm of optical thickness to your imaging train, ensuring back focus can be precisely managed. This updated -26 model replaces the discontinued EFW-7x50, now with an upward-facing USB Type-C port.\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\u003e7-Position Carousel for 50mm Square Filters\u003c\/h3\u003e\n\u003cp\u003eDesigned specifically to prevent vignetting on large-format sensors, this filter wheel accommodates seven unmounted 50mm x 50mm square filters with a supported thickness from 3mm to 4mm. The internal carousel is driven by a high-precision NPM stepper motor from Japan, allowing for precise, reliable and bidirectional filter selection. This capacity lets you load a full LRGB and narrowband filter set for imaging sessions without manual filter changes.\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\u003eDirect-Bolt Integration and a 16mm Optical Path\u003c\/h3\u003e\n\u003cp\u003eThe EFW-7x50-26 creates a solid imaging train by bolting directly to the camera body of the ZWO ASI461MM Pro and the telescope side of the ZWO OAG-L-68. The wheel contributes a fixed 16mm of optical path length, a critical and known value that simplifies back focus calculations for your entire 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\u003eEFW-7x50-26 vs. EFW-7x50: Upward-Facing USB-C\u003c\/h3\u003e\n\u003cp\u003eThis -26 model is a direct replacement for the previous EFW-7x50, with a revised USB interface and housing. The main changes ZWO lists are:\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eUpgraded Port:\u003c\/strong\u003e The original side-facing USB port has been replaced with an upward-facing USB Type-C port.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eStreamlined Housing:\u003c\/strong\u003e The slots on the sides of the housing, which previously accommodated the side port, have been removed.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCable Requirement:\u003c\/strong\u003e This new version requires a standard USB Type-C cable for power and data; the original USB cable is no longer compatible.\u003c\/li\u003e\n\u003c\/ul\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 primary purpose of the ZWO EFW-7x50-26?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe ZWO EFW-7x50-26 is designed for advanced astrophotographers using large-format monochrome cameras, such as the ZWO ASI461MM Pro. It automates the process of switching between up to \u003cstrong\u003e7 different 50mm square filters\u003c\/strong\u003e (e.g., LRGB, Ha, SII, OIII) without needing to touch the telescope, enabling fully remote or scripted imaging sessions.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat filters are compatible with the EFW-7x50-26?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThis filter wheel is made for \u003cstrong\u003e50mm x 50mm square unmounted filters\u003c\/strong\u003e. It is optimized for filters that are \u003cstrong\u003e3mm thick\u003c\/strong\u003e, but the internal mechanism can support a thickness range from 3mm to 4mm.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eHow does the 16mm optical length of the EFW-7x50-26 affect back focus with an ASI461MM Pro?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe 16mm optical length is the amount of back focus the filter wheel itself uses. Add it to the camera's own back focus and the thickness of the ZWO OAG-L-68, then make up the rest of the distance your flattener or reducer needs with spacers.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eDoes the ZWO EFW-7x50-26 require an external power supply?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eNo. The EFW-7x50-26 is powered and controlled entirely through its \u003cstrong\u003esingle USB Type-C connection\u003c\/strong\u003e. It can be connected to a computer, a ZWO ASIAIR, or the USB ports of a ZWO ASI cooled camera.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhy are 50mm square filters important when imaging the Cygnus Loop (NGC 6960) with a fast astrograph?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eA large target like the Cygnus Loop, imaged with a large sensor and a fast optical system (e.g., f\/4 or f\/5), produces a steep light cone. Smaller 2-inch round filters would cause significant vignetting, darkening the corners of the image. The \u003cstrong\u003e50mm square format\u003c\/strong\u003e of the EFW-7x50-26 provides a large clear aperture needed to fully illuminate the sensor, ensuring even brightness from edge to edge.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat software can I use to control the ZWO EFW-7x50-26?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe filter wheel is compatible with a wide range of software. It works seamlessly with ZWO's own \u003cstrong\u003eASIAIR\u003c\/strong\u003e controllers and \u003cstrong\u003eASIStudio\u003c\/strong\u003e software. It is also supported through \u003cstrong\u003eASCOM\u003c\/strong\u003e and the ZWO SDK, so it works with ASCOM-compatible capture programs.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003ctable class=\"DAV-specifications\"\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003eModel\u003c\/td\u003e\n\u003ctd\u003eEFW-7x50-26 (replaces the discontinued EFW-7x50)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFilter Positions\u003c\/td\u003e\n\u003ctd\u003e7\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eSupported Filters\u003c\/td\u003e\n\u003ctd\u003e50 x 50 mm square unmounted filters, 3 mm thick (3 to 4 mm supported)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOptical Path Length\u003c\/td\u003e\n\u003ctd\u003e16 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eBody Construction\u003c\/td\u003e\n\u003ctd\u003eCNC-machined aircraft-grade aluminum\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eMotor\u003c\/td\u003e\n\u003ctd\u003eNPM (Japan) stepper motor, bidirectional rotation\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eConnectivity\u003c\/td\u003e\n\u003ctd\u003eUpward-facing USB Type-C\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003ePower\u003c\/td\u003e\n\u003ctd\u003eUSB powered, no external power supply\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eControl\u003c\/td\u003e\n\u003ctd\u003eASIAIR, ASCOM, and ZWO SDK\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eDriver\u003c\/td\u003e\n\u003ctd\u003eDriver-free\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCamera Side Connection\u003c\/td\u003e\n\u003ctd\u003eBolts directly to the ZWO ASI461MM Pro\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eTelescope Side Connection\u003c\/td\u003e\n\u003ctd\u003eBolts to the ZWO OAG-L-68 large off-axis guider\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eDiameter\u003c\/td\u003e\n\u003ctd\u003e239 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eWeight\u003c\/td\u003e\n\u003ctd\u003e1190 g\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eWarranty\u003c\/td\u003e\n\u003ctd\u003e2 years\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cul class=\"DAV-grid\"\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eEFW-7x50-26 Filter Wheel\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 1\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003e2.0 x 75 mm Phillips Screwdriver\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 1\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003e50 x 50 mm Filter Masks\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 10\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eDarkening Rings Set\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 1\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eM2.5 x 6 Screws\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 12\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eM2 x 4 Screws (26 pcs per bag)\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 2\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003e2 m USB 2.0 Right-Angle Cable\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 1\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003e0.5 m USB 2.0 Right-Angle Cable\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 1\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/li\u003e\n\n\u003cli\u003e\n\u003ca href=\"https:\/\/davidastro.com\/pages\/zwo-warranty-policy\" rel=\"noopener\" target=\"_blank\"\u003eZWO Warranty\u003c\/a\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"ZWO","offers":[{"title":"Default Title","offer_id":67952829464861,"sku":"ZWO-EFW-7x50-26","price":599.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/files\/zwo-efw-7x50-26-electronic-filter-wheel-1.jpg?v=1793721243","url":"https:\/\/davidastro.com\/en-int\/products\/zwo-electronic-filter-wheel-efw-7x50-26-7-x-50mm-square","provider":"David Astro","version":"1.0","type":"link"}