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Explore Scientific 3″ Flattener and .7X Focal Reducer

Explore Scientific 3″ Flattener and .7X Focal Reducer


In Stock

Explore Scientific’s 3” Field Flattener .7x Focal Reducer is a multi-faceted accessory designed to enhance your astrophotography experiences. As a field flattener, this piece addresses the edge-of-field aberrations caused by curved focal planes to ensure your night at the eyepiece will result in crisp, true images.

As a focal reducer, this device will reduce your f-ratio by .7, which results in a wider field of view, brighter images and less exposure time. Recommended for our 127mm and 152mm refracting telescopes, this field flattener/focal reducer boasts fully multi-coated optics and comes with 2 adapters to accommodate different focuser sizes.

While technically this was designed for the F/8 system, through user experiences and our subsequent testing we have concluded that our 3″ Flattener / Reducer performs very well with our F/7.5 refractors.

In Stock



The 3-Inch Focal Reducer and Field Flattener by Explore Scientific is a versatile accessory made to augment your astrophotography adventure. As a field flattener, this accessory will take care of annoying edge-of-field aberrations brought about by curved focal planes, resulting in clear, sharp images. As a focal reducer, this accessory will reduce your focal ratio by 0.7 for a wider field of view and increased image illumination in shorter exposure intervals.

Explore Scientific recommended this accessory for their 127 mm and 152 mm APO refractors. Features fully multi-coated optics and comes with a 3-inch Nosepiece, 2 adapters for various focuser sizes and a male T-thread adapter for the camera.


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  • 3-inch .7x Focal Reducer & Field Flattener
  • 3-inch Nosepiece Adapter
  • 2 adapters for various focusers
  • T-Thread Adapter


Description3″ Field Flattener .7x Focal Reducer for ED APO 152mm F/8 and ES Refractors down to F/7.5
Item NumberFFFR507X-00
Weight1.4lb; .64kg

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