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Orion Telescopes
Orion 3" Field Flattener for EON 115/130 EDT Refractors
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  • Optimizes flat-field imaging performance of the EON 115mm or EON 130mm ED Triplet (EDT) refractor
  • Corrects field curvature distortions to keep stars sharp all the way to the edge of camera sensors
  • Threads directly onto telescopes' 3" focuser drawtube for ultra-rigid connection
  • Secure, wide M48 threaded camera attachment optimized for use with DSLRs and other large-sensor cameras
  • Fully multi-coated optics for maximum light throughput and bright images

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Item #  08671

Boost the flat-field imaging performance of your EON refractor with this handy Field Flattener. Designed for use with Orion EON 115mm and EON 130mm ED Triplet (EDT) refractor telescopes, the Orion 3" Field Flattener minimizes field curvature distortions that can otherwise elongate stars at the edge of the field-of-view. With the Field Flattener installed, every exposure will exhibit tack-sharp stars all the way to the edge of the imaging field. Fully multi-coated, two-element optics ensure maximum light transmission to preserve image brightness and clarity. Since the Orion Field Flattener for EON 115/130 EDT Refractors does not act as a reducer, it will not alter the focal length of the EON telescope it's used with.   

One side of the Orion 3" Field Flattener for EON Refractors threads directly onto the 3" focuser of the EON 115mm or EON 130mm telescope, while the other end features wide, M48 threads to reduce vignetting when used with DSLRs and other large-sensor cameras. This secure threaded connection ensures a rigid connection with zero flexure. The M48 threads are wider than standard M42 "T-threads" found on some other field flatteners to minimize vignetting and provide better illumination of full frame camera sensors. Requires a compatible wide T-ring for use with DSLRs (sold separately).

The 3" Field Flattener has a backfocus, or flange focal distance, of 51.5mm, though it is known to be effective at up to 5mm on either side (46.5mm - 56.5mm). It adds 88.8mm of mechanical length to an imaging train.

The Orion 3" Field Flattener for EON 115/130 EDT Refractors weighs 1 lb., 2oz. Dust caps included.


Limited Warranty against defects in materials or workmanship for one year from date of purchase. This warranty is for the benefit of the original retail purchaser only. For complete warranty details contact us at 800-447-1001.


Please note this product was not designed or intended by the manufacturer for use by a child 12 years of age or younger.

Product Support
Visit our product support section for instruction manuals and more
  • Coatings
    Fully multi-coated
  • Number of elements
  • Mounting
  • Weight (oz.)
  • Additional included accessories
  • Other features
  • Warranty
    One year

Orion 3" Field Flattener for EON 115mm/130mm ED Triplet Refractor Telescopes
Dust caps

Orders received by 1pm Eastern Standard Time for in-stock items ship the same business day. Order received after noon will ship the next business day. When an item is not in-stock we will ship it as soon as it becomes available. Typically in-stock items will ship first and backordered items will follow as soon as they are available. You have the option in check out to request that your order ship complete, if you'd prefer.

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