{"product_id":"ioptron-fa30","title":"iOptron iAFS3 - 3-inch Inline Automatic Focuser","description":"\u003cul class=\"DAV-feature-list\"\u003e\n\u003cli\u003e3-inch inline auto focuser with iLock™ technology\u003c\/li\u003e\n\u003cli\u003eSupports heavy imaging payloads up to 6kg\u003c\/li\u003e\n\u003cli\u003e68mm clear aperture minimizes vignetting\u003c\/li\u003e\n\u003cli\u003ePrecise 0.4um focusing resolution\u003c\/li\u003e\n\u003cli\u003e30mm of drawtube travel distance\u003c\/li\u003e\n\u003cli\u003eASCOM and INDI compliant for computer control\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\u003eiOptron iAFS3 - 3-inch Inline Automatic Focuser\u003c\/h2\u003e\n\u003cp\u003eThe iOptron iAFS3 is a 3-inch inline automatic focuser engineered to eliminate mechanical shift, supporting imaging payloads up to 6kg with its patented iLock™ technology. A generous 68mm clear aperture provides unvignetted fields for large sensors, while the stepper motor achieves a focusing resolution of 0.4um over 30mm of travel. Weighing 1062g and featuring dual USB-C ports, the iAFS3 integrates seamlessly into advanced imaging setups requiring absolute focus stability.\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\u003eiLock™ Technology: Zero-Shift Focusing for 6kg Payloads\u003c\/h3\u003e\n\u003cp\u003eAt the core of the iAFS3 is iOptron's iLock™ system, which uses a lead worm movement to passively lock the drawtube's position the instant the motor stops. This design prevents any focus drift or slippage, even when a heavy 6kg payload of a camera, filter wheel, and off-axis guider is pointed near the zenith. This mechanical certainty ensures that the focuser's precise 0.4um step size translates directly to sharp stars, without any backlash or flexure compromising your data.\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\u003eTriple Control System: ASCOM, Onboard Buttons, and Manual Override\u003c\/h3\u003e\n\u003cp\u003eThe iAFS3 offers three distinct methods of control for complete flexibility in the field. For fully automated sessions, it connects to your PC via one of two USB-C ports and is controlled through ASCOM or INDI drivers in software like NINA or SGP, using data from the built-in temperature sensor to maintain focus all night. For quick adjustments at the telescope, integrated motorized buttons allow for powered focusing without a computer, while a manual override wheel gives you tactile control for initial setup or situations where power is unavailable.\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\u003eEngineered for Large Imaging Trains: 68mm Aperture and 30mm of Travel\u003c\/h3\u003e\n\u003cp\u003eDesigned specifically for serious astrophotography, the iAFS3 features a large 68mm clear aperture to illuminate full-frame and larger sensors without vignetting. Its 30mm of drawtube travel provides sufficient range to achieve focus with various accessories and optical configurations. The focuser also includes a camera angle adjustment mechanism, allowing you to perfectly frame your target without disturbing the optical train. While a 2\" visual back is included, you will need to acquire the appropriate telescope-side adapter to match your specific instrument.\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\u003eiOptron iAFS3 vs. iAFS2: Choosing the Right Focuser Size\u003c\/h3\u003e\n\u003cp\u003eThe primary difference between the iAFS3 and its 2-inch sibling, the iAFS2, is the clear aperture and intended application. The iAFS2 is a more compact and lighter option, ideal for smaller refractors and systems using APS-C or smaller sensors where the larger barrel of the iAFS3 is unnecessary.\u003c\/p\u003e\n\u003cp\u003eYou should choose the 3-inch iAFS3 when your imaging train involves a full-frame or larger format sensor, or when you are using a large aperture telescope where a 2-inch focuser would become a bottleneck in the light path. The iAFS3's 68mm clear aperture is essential for preventing vignetting and ensuring even illumination across these larger fields of view.\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 benefit of the iOptron iAFS3's iLock™ technology?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe iLock™ technology uses a lead worm drive that passively locks the focuser's position when the motor is not moving. This completely prevents the drawtube from slipping or shifting under the weight of a heavy camera, ensuring your focus remains perfect regardless of the telescope's orientation. It's critical for maintaining sharpness during long exposures or automated imaging runs.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eHow does the iOptron iAFS3 handle a heavy payload on a large SCT?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe iAFS3 is rated for a \u003cstrong\u003emaximum payload of 6kg (13.2 lbs)\u003c\/strong\u003e, making it more than capable of handling a typical imaging train with a cooled camera, large filter wheel, and off-axis guider. The rigid, all-metal body and iLock mechanism ensure there is no flexure or drift, even on a system with a moving primary mirror like a Schmidt-Cassegrain Telescope.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eCan I control the iOptron iAFS3 without a computer?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes. The iAFS3 has two non-computer control methods. It features \u003cstrong\u003eonboard motorized focusing buttons\u003c\/strong\u003e for powered, push-button adjustments at the telescope. It also includes a \u003cstrong\u003emanual focusing wheel\u003c\/strong\u003e that overrides the motor, allowing for fine, tactile control without any power required.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat adapters do I need to connect the iOptron iAFS3 to my telescope?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe iOptron iAFS3 does \u003cstrong\u003enot\u003c\/strong\u003e include a telescope-side adapter. You must purchase an adapter specifically designed to connect the iAFS3 to your telescope's particular rear thread or visual back type (e.g., M68, SCT 3.25\", etc.). iOptron offers a range of optional adapters to fit various OTAs.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat is the purpose of the built-in temperature sensor on the iAFS3?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe built-in temperature sensor allows automatic focusing software (via ASCOM\/INDI) to monitor ambient temperature changes throughout the night. As the temperature drops, the optical tube can contract, causing the focal point to shift. The software uses the sensor's data to trigger periodic refocusing routines, ensuring your images remain critically sharp from dusk till dawn.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWill the iOptron iAFS3 cause vignetting with my full-frame camera on a fast refractor?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe iAFS3 is specifically designed to prevent vignetting in such scenarios. Its large \u003cstrong\u003e68mm clear aperture\u003c\/strong\u003e provides a wide, unobstructed light path that can fully illuminate sensors up to and beyond the standard 35mm full-frame format, even when used with fast optical systems.\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\u003eFocuser Size\u003c\/td\u003e\n\u003ctd\u003e3\"\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFocuser Type\u003c\/td\u003e\n\u003ctd\u003eInline Auto Focuser with iLock™\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eMaximum Payload\u003c\/td\u003e\n\u003ctd\u003e6kg\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eClear Aperture\u003c\/td\u003e\n\u003ctd\u003e68mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eDrawtube Travel\u003c\/td\u003e\n\u003ctd\u003e30mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFocusing Resolution\u003c\/td\u003e\n\u003ctd\u003e0.4um\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eDrive System\u003c\/td\u003e\n\u003ctd\u003eStepper motor\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eComputer Control\u003c\/td\u003e\n\u003ctd\u003eYes (ASCOM and INDI)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eAutomatic Focusing\u003c\/td\u003e\n\u003ctd\u003eYes\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eManual Control\u003c\/td\u003e\n\u003ctd\u003eMotorized Buttons \u0026amp; Manual Override Wheel\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003ePorts\u003c\/td\u003e\n\u003ctd\u003e2x Type-C USB2.0\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eTemperature Sensor\u003c\/td\u003e\n\u003ctd\u003eYes (Built-in)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCamera Angle Adjustment\u003c\/td\u003e\n\u003ctd\u003eYes\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eDimensions\u003c\/td\u003e\n\u003ctd\u003e94 x 133 x 108mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eWeight\u003c\/td\u003e\n\u003ctd\u003e1062g\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eShipping Weight \u0026amp; Dimensions\u003c\/td\u003e\n\u003ctd\u003e4 lbs, 11 x 8 x 7 in\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\"\u003eiAFS3 Focuser Body\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\" Visual Back\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\/ioptron-warranty-policy\" rel=\"noopener\" target=\"_blank\"\u003eiOptron 2-Year Limited Warranty\u003c\/a\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"iOptron","offers":[{"title":"Default Title","offer_id":52917289779485,"sku":"IOP-FA30","price":755.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/files\/iOptron-iAFS3-iOptron-3-Inline-Automatic-Focuser-1_ece6b400-c720-4f0e-bc74-f72cf6d18645.jpg?v=1789141981","url":"https:\/\/davidastro.com\/products\/ioptron-fa30","provider":"David Astro","version":"1.0","type":"link"}