Calculadora de Campo de Visão
Calcule o campo de visão real do seu telescópio com diferentes oculares.
°
mm
mm
True Field of View
1.083 °
Ampliação48.0 ×
True FOV (arcmin)65.0 '
True Field of View vs Apparent FOV of Eyepiece
Formula
## 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.
Exemplo Resolvido
52° AFOV eyepiece at 48×.
- 01Magnification = 1200 / 25 = 48×
- 02TFOV = 52 / 48 = 1.083° = 65.0 arcmin
- 03This fits about two full Moons side by side.
Perguntas Frequentes
What AFOV do common eyepiece types have?
Plossl: 50-52°, Erfle/wide-angle: 65-68°, Nagler/ultra-wide: 82°, Ethos: 100°.
How do I find objects in a narrow FOV?
Use a lower magnification eyepiece (wider TFOV) to locate objects, then switch to higher magnification for detail.
Does the true FOV change with a Barlow?
Yes. A 2× Barlow doubles the magnification, halving the true field of view.