视场计算器公式

## True Field of View

**TFOV = AFOV / Magnification**

The apparent field of view (AFOV) is a property of the eyepiece design (e.g., 52° for Plossl, 68° for wide-angle, 82° for ultra-wide). Dividing by magnification gives the actual sky patch visible.

The full Moon is about 0.5° across, useful as a reference.

计算示例

52° AFOV eyepiece at 48×.

  1. Magnification = 1200 / 25 = 48×
  2. TFOV = 52 / 48 = 1.083° = 65.0 arcmin
  3. This fits about two full Moons side by side.