A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
From: Joe Wong
Date: 2022 Sep 29, 01:18 -0700
Netflix has yet released another animated movie called 'The Sea Beast' for us to reminisce and enjoy our maritime culture and histories. Set in 1700s-ish era(tricornes,wigs), the movie tells the story of a particular 'sea monster' hunter Jacob and a young stowaway girl who joins him and his crew on their quest to search and kill the elusive 'Red Bluster',which after a misadventure led the hunter and the girl to befriend the creature. There's a scene in which the protagonist Jacob uses the sextant to shoot the sun while riding on the back of the Red Bluster.The movie then switches into a view through the sextant telescope, possibly the very first depiction of an actural sextant sight in any movies. By looking at the motion of the sextant sight,it is obviously that the character tries to bring the sun down to a position that is a little under the horizon,and then he let the sun to rise on its own until the lower limb kisses the horizon, a method appreciated by experienced navigators.(The movie sadly did not depict a 'swinging sun', a common practice in the end to do tangency checks) The image of the sextant view itself is errorneous, although the director or whoever rendered this scene is quite commendable for having an accurate idea on sextant sights being vertically split. Just not in the way they presumed to be: a sharp line cuts the sight in half,with only half the sun and half the horizon visible,the other halves being completely hidden. We know in actual practice, that is not the case,there is no sharp line in the middle if you are observing through the telescope, refractions in the telescope optics would enable us to see a more or less whole yet translucent sun, superimposed over the horizon image. Images depicted in the movie can only be observable if you remove the telescope on the sextant and look directly through the mirrors(or using any antique octant which usually doesnot have a telescope fitted)
Still, it's quite fun to see a proper sextant sight on the big screen,each time a sextant appears on the movie would let layman audiences wonder what would be the view through these eyepieces, this movie fullfills these wonders.