Compare calculators
Both calculators run independently — change the inputs on either side to compare results.
Astronomy
Light Pollution Sky Quality Calculator
Estimate the faintest star visible through your telescope by combining sky brightness, aperture, altitude, observer age, and moon phase. Useful for planning deep-sky sessions at any site.
Fill in the required fields to see your result.
Astronomy
Astrophotography Exposure Calculator
Calculate the recommended sub-frame exposure time for deep-sky astrophotography based on your telescope, camera, and sky conditions. Ideal for planning imaging sessions targeting galaxies, nebulae, or star clusters.
Fill in the required fields to see your result.
Key differences
| Light Pollution Sky Quality Calculator | Astrophotography Exposure Calculator | |
|---|---|---|
| Category | Astronomy | Astronomy |
| Inputs required | 4 | 4 |
| Result | Limiting Magnitude (mag) | Optimal Exposure Time (seconds) |
| What it does | Estimate the faintest star visible through your telescope by combining sky brightness, aperture, altitude, observer age, and moon phase. Useful for planning deep-sky sessions at any site. | Calculate the recommended sub-frame exposure time for deep-sky astrophotography based on your telescope, camera, and sky conditions. Ideal for planning imaging sessions targeting galaxies, nebulae, or star clusters. |