ZWO 90APO+AM3N bundle Vespera This is a field flattener

This is a field flattener for refractor-type telescopes with a focal ratio of f/5 to f/7

fuel filter

5 mm  Included adapter threads M42 male top (M54 top sold separately) Optional Filter Slider Threads Both M42 male and M54 male Origin 🇺🇸 Designed and built in Tucson

Optimized for APS-C sized sensors

The Everbrite is offered in both 1¼" and 2" models

ZWO 90APO+AM3N bundle Vespera This is a field flattenerPackage Includes: ZWO FF90 APO Astrograph f 6. 8 609mm focal length ZWO AM3N Harmonic EQ Mount ZWO TC40 Carbon Fiber Tripod PE160 Extension Pier The FF90 APO's 609mm f 6. 8 optics cover a full frame, 44mm imaging circle, and can be used for both visual observation and astrophotography. The telescope's four element designincluding an ED elementmeans no more precisely calculating your backfocusif you've got accurate focus, you'll get sharp stars out to