You select your equipment from dropdown menus, choose a target (like the Orion Nebula), and click "Add to View." The tool overlays a colored rectangle representing your sensor over a real astrophotography image of the target.
Telescope Field of View - How much can you see? - Space Math @ NASA
See exactly how deep-sky objects (DSOs) fit your sensor. astro fov calculator top
FOV(degrees)=Sensor Dimension (mm)×57.3Telescope Focal Length (mm)FOV open paren degrees close paren equals the fraction with numerator Sensor Dimension (mm) cross 57.3 and denominator Telescope Focal Length (mm) end-fraction
An astro FOV calculator is a digital tool that simulates your imaging frame. It overlays your camera sensor's rectangular boundary onto a star map. You select your equipment from dropdown menus, choose
Beginners and quick equipment compatibility checks.
| Tool Name | Platform | Key Features | Target User | | :--- | :--- | :--- | :--- | | | Web | Three dedicated modes for visual, imaging, and binoculars; extensive equipment and target databases; visual simulation of object framing | All skill levels | | BINTEL FOV Calculator | Web | Newly launched, beta, photographic and visual scenarios; uses DSS2 Colour, PanSTARRS catalogues; supports custom equipment | Intermediate to advanced | | Stellarium Mobile / Stellarium Labs | Mobile & Web | Popular planetarium app with an integrated FOV Simulator; simulates views through eyepieces and cameras; connects to telescope control | All skill levels | | FOViewer Deluxe | Android | Simulates the view through your telescope with chosen eyepieces; supports custom telescopes, eyepieces, Barlows, and cameras; includes GPS and compass | Amateurs and intermediates | | Telescope Eyepiece Calculator | iOS (iPhone, iPad, Apple Watch) | 100% offline tool; supports custom eyepiece types, Barlow/reducer multipliers; night mode and haptic feedback | All skill levels | | Telescope Calculator Pro | Android | Calculates a wide range of parameters including FOV, magnification, exit pupil, angular resolution; provides visualizations | All skill levels | | KStars | Desktop (Windows, macOS, Linux) | Open-source planetarium with an FOV editor to calculate and display FOV for equipment; integrates with INDI for telescope control | Advanced | FOV(degrees)=Sensor Dimension (mm)×57
This is a common beginner issue. The difference often comes down to the of your eyepiece. Many eyepieces, especially budget-friendly ones, may not deliver their advertised AFOV. Always verify your eyepiece's specifications.
Use a calculator to plan 3-4 eyepieces that cover these FOV ranges: