D800E的分辨率

Thom大婶又开始发烧胡说了。哦，不对，他也是抄的。意思就是买个800E就可以体验一下间谍卫星在轨分辨率高于一米是啥样子的了。

拿低端民品开军品的玩笑这还是头一朝。

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How Good is the Q? Feb 8 (commentary)--I'm going to let someone else do the talking: "I’ve spent the past 45 years involved in the analysis and design trades of spaceborne imaging systems (like the earth viewing Geoeye-1 telescope in orbit today), and Q is a wonderful, insightful and useful parameter. Q can be shown to be equal to wavelength x fno / pixel pitch. If we ignore the use of Bayer filtered pixels and do the calculation on a monochromatic basis (without a de-aliasing filter), for a Q=2 D800E (fully satisfying the Nyquist criterion at 0.55 microns), the fno turns out to be f/17.7. Thus an f/8.9 lens aperture setting on the D800E gives you a Q=1 system, which makes the D800E equivalent from a sampling standpoint to the Geoeye-1 telescope (which has a Q=0.95). In fact, many spaceborne imagers are about Q=1, which has turned out over the years to be a good compromise between resolution (NIIRS, if you are familiar with the government image quality measure) and low light performance (i.e. , SNR). And it’s interesting to note that the use of a lens set at f/8 (often the aperture that delivers the best quality image – i.e., best MTF) dovetails nicely with the achievement of a Q=1 D800E imaging camera.    So one could consider theD800E, at f/8, to be a miniature Geoeye-1 telescopic camera. The D800E has hit the traditional sweet spot for earth imaging satellite systems!"

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GeoEye－1的分辨率数字

Imaging & Collection Specifications

Launch Date	September 6, 2008
Camera Modes	Simultaneous panchromatic and multispectral (pan-sharpened) Panchromatic only Multispectral only
Resolution	0.41 m / 1.34 ft* panchromatic (nominal at Nadir)  1.65 m / 5.41 ft* multispectral (nominal at Nadir)

所有跟帖： 

• 不明白他在说什么 -云漫- ♂ (155 bytes) () 02/09/2012 postreply 08:07:57

• 早会听prez无聊时上网看到的。你是对的。整体系统里机光电分系统里，机电不再是障碍 -U96- ♂ (89 bytes) () 02/09/2012 postreply 08:21:11

• 两眼一麻黑， 没法Q了 -吴聚- ♂ (0 bytes) () 02/09/2012 postreply 09:07:43

• 老U看来是长草了，自打D800出来后， 不仅尼康粉 -天逸- ♂ (55 bytes) () 02/09/2012 postreply 09:35:01

• 没长草，按自己的计划来，不想拉人下水 -U96- ♂ (311 bytes) () 02/09/2012 postreply 09:48:42

• 老U玩起棚拍和NEX了，不过无论 -天逸- ♂ (154 bytes) () 02/09/2012 postreply 10:41:43

• 提醒一下Nex新一代用的是D7000水平的CMOS -U96- ♂ (212 bytes) () 02/09/2012 postreply 10:47:42

• Nex5N确实不错，不过，要考虑到用另一套镜头系统就很麻烦了 -天逸- ♂ (202 bytes) () 02/09/2012 postreply 11:39:22

• nex接环加peaking不用另配一套系统 -U96- ♂ (82 bytes) () 02/09/2012 postreply 11:55:10

• 可是对焦还得手动吧，老了，还是自动吧 -天逸- ♂ (0 bytes) () 02/09/2012 postreply 12:02:22

• 旁听你们的讨论， -空心竹- ♀ (50 bytes) () 02/09/2012 postreply 12:04:35

• 1系列还是另一套镜头。加自动接环可以用AF，不过暗光性能soso -U96- ♂ (75 bytes) () 02/09/2012 postreply 12:41:49

• 一半同意老u的观点，不会太快，４－５年吧 -大大仙- ♂ (0 bytes) () 02/09/2012 postreply 12:06:56

• 器材寿命+观念惯性。但感觉现在观念惯性比胶片进入数字时代小得多 -U96- ♂ (304 bytes) () 02/09/2012 postreply 12:47:26

• 天兄有钱树，进 D4 + D800E 的了！ -enTiger744- ♂ (0 bytes) () 02/09/2012 postreply 12:00:41

• 呵呵。我也想进D4， 还是太贵了，而且一个全福和一个半幅比较好match -天逸- ♂ (0 bytes) () 02/09/2012 postreply 12:04:46

• 纯理论的， 看不懂啊！ -Alabama- ♂ (0 bytes) () 02/09/2012 postreply 10:27:11

• 呵呵， 老U是见着新器材就真睡不着觉了。。。 -enTiger744- ♂ (0 bytes) () 02/09/2012 postreply 11:54:32

• ：－） 兴奋点嘛 -U96- ♂ (0 bytes) () 02/09/2012 postreply 11:58:54

• 等U班的好作品了，特别是棚拍哈，新领域，更刺激 -akuan- ♂ (0 bytes) () 02/09/2012 postreply 22:55:20