Telescope Comparison Calculator
Compare two telescopes by f/ratio, light-gathering power, and angular resolution.
Inputs
Results
Light Gathering (A/B)
1.78×
Scope A f/ratio5.9
Scope B f/ratio4.9
Resolution A0.57 arcsec
Resolution B0.76 arcsec
How to Use This Calculator
- Enter Scope A Aperture (in), Scope A Focal Length (mm), and Scope B Aperture (in).
- Set Scope B Focal Length (mm).
- Review the Light Gathering (A/B) (×) result.
- Use Scope A f/ratio and Scope B f/ratio to inform your decision.
- Use the chart to visualize the results and explore different scenarios by adjusting inputs.
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