spyglass telescope

spyglass telescope optical instrument magnification lens viewfinder observation astronomy stargazing navigation exploration nautical marine adventure discovery distant objects long distance sighting outdoor sightseeing nature wildlife birdwatching astronomy equipment sky stars planets celestial objects horizon scouting marine exploration travel journey expedition lookout periscope handheld scope optical lens field of view focusing zoom spotting nature observation adventure equipment travel gear exploration tool sightseeing optics astronomy observation device long range viewing navigation tool outdoor activity marine telescope handheld telescope optical viewing instrument skywatching research observation gear telescope lens optics gear