Explore Scientific

3" Flattener and .7X Focal Reducer

SKU: FFFR507X-00


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  • Regular price $479.99

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  • For use with Explore Scientific ED127-152-165 Air-Spaced Triplets
  • 3.0-inch O.D. with Adapters for Explore Scientific Focusers
  • 0.7x Reducer and Field Flattener

NOTE: Separate adapter required for the ES 2.5" HEX focuser.

Explore Scientific's 3-inch Field Flattener/0.7x 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 0.7, which results in a wider field of view, brighter images and less exposure time. This field flattener/focal reducer boasts fully multi-coated optics and comes with 2 adapters to accommodate different focuser sizes.

The field flattener/focal reducer offers 55 mm of back focus from the rear flange. The M42x0.75 adapter is 6.25 mm thick.

While technically this was designed for the F/8 system, through user experiences and our subsequent testing we have concluded that our 3-inch field flattener/reducer performs very well with our F/7.5 refractors.

  Description 3" Field Flattener .7x Focal Reducer for ED APO 152mm F/8 and ES Refractors down to F/7.5
  Item Number FFFR507X-00
  Weight 1.4lb; .64kg
  Diameter 78.3mm
  Height 90.1mm
Barcode: 812257014408