Field of View Calculators
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Camera Field of View

Film - 35mm
Film - 645 Medium Format
Film - 4x5 sheet
Digital - Four Thirds
Custom Width: mm Height: mm

Optical Instrument Focal Length: mm

Field of View: ° x °

Calculations from Widefield Astrophotography by Robert Reeves

Eyepiece True Field of View

Magnification Data:
Focal Length: Telescope: mm Eyepiece: mm

Eyepiece Apparent Field of View: °

Actual Field of View: °