{"product_id":"askar-50p-f-3-8-quadruplet-apo-telescope","title":"Askar 50P f\/3.8 Quadruplet APO Telescope","description":"\u003cul class=\"DAV-feature-list\"\u003e\n\u003cli\u003e50mm Aperture Quadruplet APO Optics\u003c\/li\u003e\n\u003cli\u003eUltra-Fast f\/3.8 Focal Ratio\u003c\/li\u003e\n\u003cli\u003e190mm Focal Length\u003c\/li\u003e\n\u003cli\u003eNatively Flat Field for APS-C Sensors\u003c\/li\u003e\n\u003cli\u003eStandard 55mm Back Focus Requirement\u003c\/li\u003e\n\u003cli\u003eCompact 147mm Length and 1.4kg Weight\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\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\u003eAskar 50P f\/3.8 Quadruplet APO Telescope\u003c\/h2\u003e\n\u003cp\u003eThe Askar 50P f\/3.8 Quadruplet APO Telescope combines a 50mm aperture with a fast 190mm focal length for ambitious wide-field imaging. Its quadruplet Petzval optical design delivers a natively flat field suitable for up to APS-C format sensors, while its compact 147mm length and 1.4kg weight make it the definitive grab-and-go astrograph.\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\u003eUltra-Fast f\/3.8 Quadruplet APO Optics\u003c\/h3\u003e\n\u003cp\u003eAt f\/3.8, the Askar 50P gathers light dramatically faster than typical refractors, allowing you to capture deep signal on faint nebulae in a fraction of the time. The quadruplet Petzval design, which includes one piece of SD glass, corrects for chromatic aberration and field curvature without the need for an additional flattener, ensuring sharp, color-pure stars across the entire frame.\u003c\/p\u003e\n\u003cp\u003eThe 190mm focal length produces an expansive field of view, perfect for framing large celestial canvases. Targets like the Andromeda Galaxy (M31), the North American Nebula (NGC 7000), and the vast Rho Ophiuchi cloud complex fit comfortably within the frame of a modern APS-C sensor.\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\u003eFlat-Field Imaging for APS-C with 55mm Back Focus\u003c\/h3\u003e\n\u003cp\u003eThe Askar 50P is engineered for seamless camera integration. The optical system is optimized for 1-inch sensors but provides excellent correction for larger APS-C formats, delivering a corrected image circle without the complexity of calculating spacing for a separate reducer or flattener. This simplifies your imaging train and eliminates potential sources of tilt.\u003c\/p\u003e\n\u003cp\u003eConnection is made via a standard M48 adapter, requiring a common 55mm back focus. This is compatible with most dedicated astronomy cameras and DSLR\/mirrorless cameras using a standard M48 T-ring. The focuser also supports a back focus range from 50mm to 65mm, offering flexibility for unique imaging setups.\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\u003eCompact and Lightweight at 1.4kg for Grab-and-Go Imaging\u003c\/h3\u003e\n\u003cp\u003eDesigned for portability, the Askar 50P weighs just 1.4kg and measures a mere 147mm with its dew shield retracted. This minimal footprint makes it an ideal companion for lightweight star trackers and portable mounts, allowing you to set up a powerful imaging rig far from city lights without hauling heavy equipment.\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eSliding Dew Shield:\u003c\/strong\u003e The integrated dew shield extends to 182mm, providing excellent protection from stray light and moisture during long imaging sessions.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSolid Construction:\u003c\/strong\u003e Despite its small size, the telescope is built for rigidity, ensuring the optical elements remain perfectly collimated from your backyard to a remote dark-sky site.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eAskar 50P vs. RedCat 51: Focal Ratio and Field of View\u003c\/h3\u003e\n\u003cp\u003eWhen choosing a portable astrograph, the primary competitor to the Askar 50P is the William Optics RedCat 51. While both are excellent Petzval designs, they serve different imaging goals.\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eCompetitor Advantage (RedCat 51):\u003c\/strong\u003e The RedCat offers a slightly larger 51mm aperture and a longer 250mm focal length. This provides a tighter field of view and more image scale, which can be beneficial for framing smaller deep-sky objects.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eAskar 50P Advantage:\u003c\/strong\u003e The 50P's key advantage is its f\/3.8 focal ratio, which is significantly faster than the RedCat's f\/4.9. This allows for roughly 68% more light gathering in the same amount of time, drastically reducing required exposure times. Its 190mm focal length also captures a wider true field of view, ideal for the largest nebulae and mosaics.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003eYour choice depends on your primary targets. For the widest possible vistas and the shortest possible exposures, the Askar 50P is the superior instrument.\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\"\u003eDo I need a field flattener for the Askar 50P telescope?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eNo. The Askar 50P uses a \u003cstrong\u003equadruplet Petzval optical design\u003c\/strong\u003e, which has a built-in corrector. It produces a natively flat field suitable for up to APS-C sensors without requiring any additional flattener or reducer.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat is the main advantage of the Askar 50P's f\/3.8 focal ratio?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eAn \u003cstrong\u003ef\/3.8 focal ratio\u003c\/strong\u003e is extremely fast, allowing the telescope to collect a large amount of light in a short period. This means you can use shorter sub-exposures to capture faint details in nebulae and galaxies, reducing issues with guiding, tracking, and changing sky conditions.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat is the correct back focus for the Askar 50P?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe recommended back focus is \u003cstrong\u003e55mm\u003c\/strong\u003e from the base of the rear M48 threads. This is the standard distance for most dedicated astronomy cameras and for DSLR\/mirrorless cameras when using a compatible T-ring. The system supports a total range of 50mm to 65mm for added flexibility.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat kind of camera sensor is the Askar 50P designed for?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe Askar 50P provides a corrected image circle that supports \u003cstrong\u003eAPS-C format sensors\u003c\/strong\u003e and is specifically optimized for 1-inch sensors. This makes it compatible with a wide range of popular CMOS astronomy cameras and many DSLR\/mirrorless models.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat kind of mount is required to image with the Askar 50P?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eWith a gross weight of only \u003cstrong\u003e1.4kg\u003c\/strong\u003e, the Askar 50P is exceptionally lightweight. It can be carried easily by compact, portable tracking mounts like the Sky-Watcher Star Adventurer or iOptron SkyGuider Pro, making it an ideal choice for a travel imaging setup.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eIs the Askar 50P's 190mm focal length suitable for large targets like the Andromeda Galaxy (M31)?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes, perfectly. The \u003cstrong\u003e190mm focal length\u003c\/strong\u003e provides a very wide field of view that is ideal for framing enormous targets. With an APS-C sensor, you can easily capture the full expanse of the Andromeda Galaxy (M31), the North American Nebula (NGC 7000), or the Veil Nebula complex in a single shot.\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\u003eAperture Size\u003c\/td\u003e\n\u003ctd\u003e50mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFocal Length\u003c\/td\u003e\n\u003ctd\u003e190mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFocal Ratio\u003c\/td\u003e\n\u003ctd\u003ef\/3.8\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eObjective Lens\u003c\/td\u003e\n\u003ctd\u003eQuadruplet Petzval APO (with one SD glass element)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eImage Circle\u003c\/td\u003e\n\u003ctd\u003eSupports APS-C format (optimized for 1-inch sensors)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eTotal Length (Dew Shield Contracted)\u003c\/td\u003e\n\u003ctd\u003e147mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eTotal Length (Dew Shield Stretched)\u003c\/td\u003e\n\u003ctd\u003e182mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eGross Weight\u003c\/td\u003e\n\u003ctd\u003e1.4kg (including tube ring and dovetail plate)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eRear-end Thread\u003c\/td\u003e\n\u003ctd\u003eM48x0.75 Adapter\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eBack Focus\u003c\/td\u003e\n\u003ctd\u003e55mm Recommended (50-65mm range supported)\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\"\u003eAskar 50P OTA\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\"\u003eManual\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\u003cli\u003e\n\u003cul class=\"DAV-grid\"\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\u003ca href=\"https:\/\/www.sharpstar-optics.com\/download_list_1\/7.html\" 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\"\u003eDownload Manual\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/a\u003e\u003c\/li\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\u003ca href=\"https:\/\/www.sharpstar-optics.com\/download_list_1\/7.html\" target=\"_blank\"\u003e\u003csvg xmlns=\"http:\/\/www.w3.org\/2000\/svg\" viewbox=\"0 0 640 512\" class=\"DAV-img-box\"\u003e\u003cpath fill=\"#0047a7\" d=\"M128 32C92.7 32 64 60.7 64 96l0 256 64 0 0-256 384 0 0 256 64 0 0-256c0-35.3-28.7-64-64-64L128 32zM19.2 384C8.6 384 0 392.6 0 403.2C0 445.6 34.4 480 76.8 480l486.4 0c42.4 0 76.8-34.4 76.8-76.8c0-10.6-8.6-19.2-19.2-19.2L19.2 384z\"\u003e\u003c\/path\u003e\u003c\/svg\u003e \n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eDownload Software \u0026amp; Drivers\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\/askar-warranty-policy\" rel=\"noopener\" target=\"_blank\"\u003eAskar 1-Year Warranty\u003c\/a\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"Askar","offers":[{"title":"Default Title","offer_id":50980013900061,"sku":"ASK-50P","price":299.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/files\/Askar-50P-Quadruplet-Telescope-1.jpg?v=1772217458","url":"https:\/\/davidastro.com\/fr-us\/products\/askar-50p-f-3-8-quadruplet-apo-telescope","provider":"David Astro","version":"1.0","type":"link"}