天哪! 我好像在在蒐集資料做學校的報告

慾罷不能, 再來一篇


所謂 Lucky imaging 也是 Speckle imaging 的一種, 只是他只取較清晰的影像做處裡(疊加),
這樣的效果比單張長時間曝光的影像有更高的解析度. 由於短時間曝光對儀器追蹤精準度的要求較較低,
做起來比較容易, 所以非常適合業餘天文使用, 這也是Webcam會被業餘天文界大量用在拍一些亮行星的原因吧. 之後可能會往拍攝暗星體發展, 或是更高超的處裡技巧.

好了, 有點頭暈了, 今天到此為止吧, 還好不用交作業啊


 

同樣節錄自 Wikipedia

Lucky imaging:

Lucky imaging is an astronomical photographic technique using a high-speed camera with exposure times short enough (100 ms or less) so that the changes in the atmosphere during the exposure are minimal. From these images, those least affected by the atmosphere (typically around 10%) are chosen and combined into a single image by shifting and adding the short exposures, yielding much higher resolution than would be possible with a single, longer exposure which includes all the frames.

...

(also called lucky exposures) is one of several speckle imaging methods used to remove atmospheric blurring. Used at a 1% selection or less, lucky imaging can reach the diffraction limit of even 2.5 m aperture telescopes, a resolution improvement factor of at least five over standard imaging systems.


Both amateur and professional astronomers have begun to use this technique. Modern webcams and camcorders have the ability to capture rapid short exposures with sufficient sensitivity for astrophotography, and these devices are used with a telescope and the shift-and-add method from speckle imaging (also known as image stacking) to achieve previously unattainable resolution. If some of the images are discarded, then this type of video astronomy is called lucky imaging. Many methods exist for image selection, including the Strehl selection method from the Cambridge group^[5] and the image contrast selection used in the Selective Image Reconstruction method of Ron Dantowitz.^[6] The recent development of EMCCDs has allowed the first high quality lucky imaging of faint objects.