极限星等

如能将其作为天文观测终端，必将在信噪比以及观测极限星等方面带来很大的提高。鉴于USB接口使用灵活、传输速率高，以及成本低廉，几乎成为了目前众多设备的标准接口。

IF it can be used as terminal of astronomy observation , it will take much benefits on SNR and limiting magnitude ,, Also , because USB interface is flexible for using , and have high transmission speed , have low cost .

在上面的图例中极限星等是9等。

In the illustration above , the limiting magnitude has been set to9 .

提出了一种计算APS探测极限星等的简单方法。

A simple method for calculating the stellar detection limit of APS is proposed .

试验和分析表明：当进行天文斑点成像观测时，该系统极限星等达到12m；

The test and analyses for the camera showed that the limit magnitude will be 12 m when it is used to do the observation of astronomical speckle imaging ;

该方法根据最佳检测原则，由信噪比阈值和APS噪声值得到APS探测信号值，再通过典型APS对0星等恒星的辐射响应求出APS相应的探测极限星等。

The APS detection signal is obtained from signal-noise ratio ( SNR ) threshold and APS total noise value based on optimal detection principle . The corresponding stellar detection limit of APS is obtained through the radiation response of typical APS to 0 magnitude star .

白天对空间目标进行观测时，采用光谱滤波技术可以提高光电系统的极限星等探测能力。

The limiting magnitude of an electro-optical system can he improved through the spectral filtering technology in daytime apace target observation .

要设置星图上显示的最暗恒星的星等，就在极限星等区域更改数值。

To set the magnitude of the faintest star which appears on the map , change the value in the Limiting magnitude field .

星图中的极限星等，即所显示的最暗星等。

The " limiting magnitude " of stars on the map , ie the magnitude of the faintest star which will be displayed .

本文给出了用几种达到不同极限星等的星系表确定宇宙分形结构上限截止尺度的公式。

A formula used to determine the upper cut off Rc of the fractal structure of the Universe is given by analysis of different apparent magnitude limited catalogues .

试观测内容包括：光度计系统与望远镜的匹配情况、仪器的稳定度的估计，观测精度、极限星等、消光归化系数的测定以及几个食双星的光电测光工作。

Among the contents of the test observation , there are the analysis of the stability of the photometer , the determination of the observation accuracy , the extinction and transformation coefficients . Also , a few eclipsing binaries are observed .

在信噪比阈值为5的情况下，得到某类APS的探测极限为6.31星等。

The stellar detection limit of one APS is 6.31 visual magnitude when the threshold of SNR is 5 .