1·When viewing extended objects, the apparent brightness seen in the eyepiece is a function only of aperture and magnification, it is not related to focal ratio.
当观察扩展光源时，目镜中所看到的亮度只跟孔径和放大率有关，它跟焦比并没有关系。
2·Or, you can calculate the exit pupil by dividing the focal length of the eyepiece (in mm) by the focal ratio of the telescope.
或者，你还可以将目镜的焦距除以望远镜的焦比来得到出瞳尺寸。
3·To calculate exit pupil, divide the aperture (in mm) by the power of the eyepiece being used.
为了计算出射光瞳，可将孔径(单位mm)除以目镜的放大倍数。
4·An eyepiece with wide apparent field (in degrees) and lower powers used on a telescope allow wider fields of view.
较宽的目镜视场搭配较低的放大率可以得到更宽的视场角。
5·Adjust the right eyepiece (No. 3 in Fig. 1), to get the visibility adaptive with operators eyesight, obtain the clear image.
调整右目镜(图1序号3)，以获得与操作者视力相适应的视度，获得清晰的图像。