Gear Database

Field Flattener for 480-700 mm Telescopes and 2" Focuser (SFF6)

Stellarvue

Field Flattener for 480-700 mm Telescopes and 2" Focuser (SFF6) is a matched reducer/flattener or field corrector for improving star shape and image scale on compatible optics.

corrector budget
Field Flattener for 480-700 mm Telescopes and 2" Focuser (SFF6)

Best Current Offer

Cloud Break Optics logo
Cloud Break Optics
In stock
$195.00

Specifications

Optics

Optical type
Reducer / field flattener
Threads
T-thread

Compatibility

Compatibility
480-700 mm Telescopes and 2" Focuser

Imaging

Camera format
2-inch / M48 imaging train
Full-frame coverage
No

Sensor / electronics

Back focus
55 mm

Specifications

Reduction factor
1.0x (no reduction)

Astrophotography Fit

Best when it is matched to the exact telescope design and installed at the specified back-focus spacing.

Field Flattener for 480-700 mm Telescopes and 2" Focuser (SFF6) should be treated as part of the optical prescription, not a generic accessory. The right reducer or corrector can flatten the field, improve corner stars, and in reducer form make the system faster and wider.

Spacing, tilt, and sensor size are the entire game. Even a premium corrector will disappoint if the camera sits at the wrong distance or the focuser cannot hold the train square.

Best paired with

  • The specific telescope model it was designed for
  • Threaded adapters and spacers that hit the published back focus
  • Cameras with sensors inside the corrected image circle

Not recommended for

  • Unmatched telescopes with different optical prescriptions
  • Rigs where back focus is already consumed by filters/OAG/rotator
  • Trying to fix guiding, focus, or collimation issues optically

Where To Buy

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Retailer Price Availability View Offer
Cloud Break Optics logo
Cloud Break Optics
Cloud Break Optics
$195.00
In stock
Updated 5/9/2026
View Offer - $195.00