Optical Tube Assembly (OTA)

An optical tube assembly, or OTA, is a telescope's tube with its optics and focuser, sold without a mount or tripod. It suits you if you already own a mount, or want to choose one to match the tube for observing or astrophotography.

Ours are Explore Scientific: AR doublet and ED and FCD100 triplet refractors from 80 to 152 mm, and the FirstLight 127 mm Maksutov-Cassegrain. For three grades of refractor compared, read AR102 vs ED102 vs ED102-FCD100.