{"product_id":"explore-scientific-2-field-flattener-for-f-5-f-7-refractors-es-ff2f5-f7","title":"Explore Scientific 2\" Field Flattener for f\/5 - f\/7 Refractors - ES-FF2F5\/F7","description":"\u003ch3 style=\"text-align: center;\"\u003eExplore Scientific f\/5 - f\/7 Field Flattener with 2\" Barrel\u003c\/h3\u003e\n\u003cul data-mce-fragment=\"1\"\u003e\n\u003cli data-open-accessibility-text-original=\"16px\" data-mce-fragment=\"1\"\u003eExplore Scientific 2\" field flattener for refractors with a focal ratio of f\/5 to f\/7\u003c\/li\u003e\n\u003cli data-open-accessibility-text-original=\"16px\" data-mce-fragment=\"1\"\u003eThis field flattener will not change (reduce) the telescope's focal length\u003c\/li\u003e\n\u003cli data-open-accessibility-text-original=\"16px\" data-mce-fragment=\"1\"\u003eFully multi-coated optics\u003c\/li\u003e\n\u003cli data-open-accessibility-text-original=\"16px\" data-mce-fragment=\"1\"\u003eEasily attaches to a a DSLR camera with user-supplied t-ring\u003c\/li\u003e\n\u003cli data-open-accessibility-text-original=\"16px\" data-mce-fragment=\"1\"\u003e38 mm of clear aperture\u003c\/li\u003e\n\u003cli data-open-accessibility-text-original=\"16px\" data-mce-fragment=\"1\"\u003eRequires 55mm of back focus\/spacing between the device and the camera sensor\u003c\/li\u003e\n\u003cli data-open-accessibility-text-original=\"16px\" data-mce-fragment=\"1\"\u003eThe body sports a premium high glossy anodizing finish\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp data-open-accessibility-text-original=\"16px\"\u003eIf you are doing astrophotography with a fast refractor, field curvature may appear in the corners of your images, making the stars smear perpendicular to the axis of the image. This is called coma -- coma is Latin for comet, because the stars look like comets. The faster the refractor, the more obvious the field curvature becomes, and as curvature increases, the closer to the center the coma appears. The larger the sensor, the worse the coma.\u003c\/p\u003e\n\u003cp data-open-accessibility-text-original=\"16px\"\u003eAstrophotographers can easily correct for coma by using a field flattener – an optical device that goes between the telescope and the camera. Field fatteners are not interchangeable, because these devices are designed to work with a small range of focal ratios.\u003c\/p\u003e\n\u003cp data-open-accessibility-text-original=\"16px\"\u003eThe Explore Scientific field flattener is designed to work with telescopes with focal ratios between f\/5 and f\/7.  Please note that this flattener does not reduce your telescope's effective focal length.  Like most field flatteners, it requires 55 mm (+\/-2 mm) of spacing between the back of the device and the camera sensor.  \u003c\/p\u003e\n\u003cp data-open-accessibility-text-original=\"16px\"\u003eAccording to Explore Scientific, this field flattener works with the following Explore telescopes:\u003c\/p\u003e\n\u003cp data-open-accessibility-text-original=\"16px\"\u003e\u003cbr\u003eDAR1020765-01\u003cbr\u003eDAR127065-02\u003cbr\u003eDAR152065-01\u003cbr\u003eES-ED0806-02\u003cbr\u003eES-ED10207-02\u003cbr\u003eFCD100-0806-01\u003cbr\u003eFCD100-10207-02\u003c\/p\u003e\n\u003cp\u003e \u003c\/p\u003e","brand":"Explore Scientific","offers":[{"title":"Default Title","offer_id":39838885773425,"sku":"EXP-ES-FF2F5\/F7","price":108.95,"currency_code":"EUR","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0851\/2766\/products\/ES-FF2F5_F7_standing_cap_and_adapter_off_jpg.webp?v=1776459118","url":"https:\/\/khanscope.com\/en-fr\/products\/explore-scientific-2-field-flattener-for-f-5-f-7-refractors-es-ff2f5-f7","provider":"Khan Scope Centre","version":"1.0","type":"link"}