{"product_id":"takahashi-epsilon-130d-1-5x-extender","title":"Takahashi Epsilon-130D 1.5x Extender","description":"\u003ch3\u003e\u003cstrong\u003eProduct Overview\u003c\/strong\u003e\u003c\/h3\u003e\u003cp\u003eThe Epsilon Extender 1.5x E-130D extends the Epsilon-130D astrograph's native 430mm f\/3.3 to 650mm f\/5.0, while carrying the same coma correction that makes the Epsilon series sharp to the edge of frame at prime focus. Seven elements in five groups do the work of both magnifying the image and holding coma in check at the same time.\u003c\/p\u003e\u003ch3\u003e\u003cstrong\u003eWho It's For\u003c\/strong\u003e\u003c\/h3\u003e\u003cp\u003eThis extender suits Epsilon-130D owners who want a longer working focal length for tighter deep-sky targets — galaxies, planetary nebulae, small clusters — without switching to a slower, narrower-field telescope. It keeps the fast, coma-corrected imaging the Epsilon series is built for, just at 650mm instead of 430mm.\u003c\/p\u003e\u003ch3\u003e\u003cstrong\u003eKey Features \u0026amp; Design\u003c\/strong\u003e\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003e7 elements in 5 groups:\u003c\/strong\u003e a full optical assembly, not a simple magnifying lens, that maintains coma correction at the extended focal length.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e1.5x extension:\u003c\/strong\u003e takes the Epsilon-130D from 430mm f\/3.3 to 650mm f\/5.0.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eΦ44mm corrected image circle:\u003c\/strong\u003e diffraction-limited performance, about 2 microns at the center and up to 8 microns at the edge of a full-frame sensor.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eM60 input \/ M54 output threads:\u003c\/strong\u003e matches the Epsilon-130D's camera angle adjuster on one side and standard M54 camera adapters on the other.\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003e\u003cstrong\u003eOptical \/ Mechanical Design\u003c\/strong\u003e\u003c\/h3\u003e\u003cp\u003eThe extender's seven-element, five-group design re-corrects coma at the longer focal length rather than simply magnifying the uncorrected image the way a basic Barlow would. Back focus is 56.2mm, the same figure the Epsilon-130D uses at prime focus, so an existing spacing setup carries over. See the \u003ca href=\"\/pages\/takahashi-back-focus-guide\"\u003eTakahashi Back Focus Guide\u003c\/a\u003e for the full chain.\u003c\/p\u003e\u003ch3\u003e\u003cstrong\u003eRecommended Uses\u003c\/strong\u003e\u003c\/h3\u003e\u003cp\u003eImaging smaller deep-sky targets — planetary nebulae, compact galaxies, globular clusters — that are undersized in the Epsilon-130D's native 430mm field; narrowband imaging where the extra focal length helps frame a target more tightly; general astrophotography where 650mm f\/5.0 suits the target better than 430mm f\/3.3.\u003c\/p\u003e\u003ch3\u003e\u003cstrong\u003eCompatibility and Accessory Notes\u003c\/strong\u003e\u003c\/h3\u003e\u003ctable\u003e\n\u003ctr\u003e\n\u003cth\u003eTelescope\u003c\/th\u003e\n\u003cth\u003eResulting focal length\u003c\/th\u003e\n\u003cth\u003eResulting focal ratio\u003c\/th\u003e\n\u003cth\u003eImage circle\u003c\/th\u003e\n\u003cth\u003eBack focus\u003c\/th\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eEpsilon-130D\u003c\/td\u003e\n\u003ctd\u003e650mm\u003c\/td\u003e\n\u003ctd\u003ef\/5.0\u003c\/td\u003e\n\u003ctd\u003eΦ44mm\u003c\/td\u003e\n\u003ctd\u003e56.2mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/table\u003e\u003cp\u003eThe extender is specific to the Epsilon-130D — the Epsilon-160ED and Epsilon-180ED each use their own dedicated 1.5x extender, matched to their own thread sizes and back focus.\u003c\/p\u003e\u003ch3\u003e\u003cstrong\u003eGood to Know Before You Order\u003c\/strong\u003e\u003c\/h3\u003e\u003cp\u003e\u003cstrong\u003eScrew-in 2\" filters aren't recommended\u003c\/strong\u003e with this extender, since Takahashi notes they can introduce reflections at this focal ratio — a filter wheel or camera-side filter mounting avoids the issue.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eAt 450g,\u003c\/strong\u003e it's light enough that it's the camera and filter wheel on the other end of the train, not the extender itself, that will drive your balance point.\u003c\/p\u003e\u003ch3\u003e\u003cstrong\u003eFrequently Asked Questions\u003c\/strong\u003e\u003c\/h3\u003e\u003cp\u003e\u003cstrong\u003eIs it difficult to set up?\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003eNo — it installs between the Epsilon-130D's camera angle adjuster and your camera on M60 and M54 threads, and the 56.2mm back focus matches the telescope's native prime-focus figure.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhat is it best used for?\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003eImaging deep-sky targets that need more reach than the Epsilon-130D's native 430mm provides, while keeping the coma correction the Epsilon series is known for.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eDoes it work for visual observing?\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003eIt's built as an imaging accessory — the corrected image circle and mechanical interfaces are designed around camera sensors rather than eyepieces.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhat else do I need with it?\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003eYour camera's own T-ring or M54 adapter to complete the connection at the 56.2mm back focus figure.\u003c\/p\u003e\u003ch3\u003e\u003cstrong\u003eBottom Line\u003c\/strong\u003e\u003c\/h3\u003e\u003cp\u003eA coma-corrected 1.5x extender that takes the Epsilon-130D to 650mm at f\/5.0 across a Φ44mm image circle, at the same 56.2mm back focus the telescope already uses at prime focus.\u003c\/p\u003e","brand":"Takahashi","offers":[{"title":"Default Title","offer_id":54047111938159,"sku":"TAK-TKA69595","price":1287.0,"currency_code":"CAD","in_stock":false}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0686\/0049\/6239\/files\/tka69595_3.jpg?v=1786913997","url":"https:\/\/ontariotelescope.com\/products\/takahashi-epsilon-130d-1-5x-extender","provider":"Ontario Telescope and Accessories","version":"1.0","type":"link"}