Grid algorithm is a preferable star field identification algorithm. But it need many stars in FOV (field of view). Thereby CCD star tracker must have large FOV or be sensitive to dim stars.

栅格算法是一种较优秀的星图识别算法，但它要求视场中有较多的恒星，从而要求星跟踪器有大的视场或高的星等灵敏度。

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Optical systems with large FOV are usually complex in design and have large distortion due to such factors as eccentric, field of view, and focal length.

大视场光学系统由于非共轴、视场、焦距等因素的影响，光学设计比较复杂，光学系统的畸变比较大。

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FOV: Allows you to customise the amplitude of your field of view.

视场：让您自选振幅你的视野。

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And because I know some of you are bursting to know, yes, there is a Field of View (FOV) slider in the graphics options.

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The sensor's 720p HD video is captured in full field-of-view (FOV) with 2 x 2 binning, which doubles the sensitivity and improves the signal-to-noise ratio (SNR).

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