2018年12月08日:小小行星的缩时景观-（Tiny Planet Timelapse）

2018年12月08日:小小行星的缩时景观-（Tiny Planet Timelapse）--原图下载

2018 December 8

Video Credit &Copyright: Brian Haidet -Music Credit:Space Walk - Silent Partner
说明: 在这颗小小行星上，你能够把大量的天空塞进30秒长的影片里。想当然耳，这些完整球形的缩时影像，是摄于地球之上；确切的地点则是美国．北卡罗莱纳州．派赫斯特镇郊的巨杉天文台。这部摄于今年9月初的影片，使用数位技术整合配置圆形鱼眼镜头的单一部相机在24小时期间朝上拍摄的影像，与及相机及镜头在另一个24小时期间朝下拍摄的影像。所取得的影像数据，然后经过处理并投影到以天底（相机的正下方）为中心的平场影框上。影片里，可见到云朵飘飞、暗影掠过、天空迴旋、与及从白画变成黑夜时，恒星在地平线附近迴绕。请继续观赏，在第二段时，投影的中心是南天极，在这颗小小行星地平面下方的地球自转轴指向。当以恒星为导星时，变成小小行星在迴旋，地平面也跟着转动，不论是白画或黑夜都遮住了一半的天空。

原文：

Video Credit &Copyright: Brian Haidet -Music Credit:Space Walk - Silent Partner
Explanation: You can pack a lot of sky watching into 30 seconds on this tiny planet.Of course, the full spherical image timelapse videowas recorded onplanet Earth, fromGrandePines Observatory outside Pinehurst, North Carolina.It was shot in early September with a single camera and circularfisheye lens,digitally combining one 24-hour period with camera and lens pointed upwith one taken with camera and lens pointed down.The resulting image data is processed and projected ontoa flat frame centered on thenadir,the point directly below the camera.Watch as clouds pass, shadows creep, and the sky cycles from day to nightwhen stars swirl around the horizon.Keep watching, though.In a second sequence the projected center is thesouth celestial pole,planet Earth's axis of rotation below the tiny planet horizon.Holding the stars fixed, the horizon itself rotates as the tinyplanet swings around the frame, hiding half the skythrough day and night.