Camera Sensor
Lens Settings
Calculation Method
Target Declination
Stars near celestial poles move slower, allowing longer exposures
Light Pollution (Bortle Scale)
Light domes visible
Planning Date
🌗
Last Quarter
59% illumination
Point Stars (No Trailing)
Recommended Max
14s
NPF Rule500 Rule
25s
Less accurate400 Rule
20s
ConservativeShooting Conditions for 12/12/2025
🌗
Last Quarter
Moon impact: high
- Fair - bright moonlight may wash out faint stars
- Acceptable conditions, may need light pollution filter
Recommended ISO
1131
Bortle 4Crop Factor
1×
Pixel Pitch
5.9µm
Understanding the Rules
- 500 Rule: Simple but often produces slight trailing on high-res sensors
- NPF Rule: More accurate - accounts for aperture and pixel density
- Declination: Stars near celestial poles (Polaris) move slower
- Star rotation: 15° per hour (360° in 24 hours)
Astrophotography Tips
- Use the widest aperture available (f/1.4-f/2.8 ideal)
- Set ISO based on light pollution conditions
- Use manual focus set to infinity (∞) and fine-tune on a bright star
- Shoot in RAW for better post-processing flexibility
- Consider a star tracker for longer exposures without trailing
- Check moon phase - new moon is ideal for Milky Way shots