Celestron Right Angle Correct Image Finderscope RASA In his own words

In his own words

Tuning the etalon to each side of the central wavelength is needed because local changes in atmospheric pressure change the refractive index of your local air mass

OTA Outer Diameter 9

With two extra eyepieces and a Barlow lens

Celestron Right Angle Correct Image Finderscope RASA In his own wordsComfortable Right Angle Design: Keeps your neck and back at ease during long sessions Correct Image Optics: Produces natural viewsideal for both day and night use 9x Magnification with 50mm Aperture: Captures bright, sharp visuals with a 5 field of view Double Crosshair Reticle: Fine etched lines help you center targets precisely without obscuring stars Adjustable Eyepiece Orientation: Rotate for the perfect viewing angle Durable Bracket & Dovetail