Star Trail Calculator
Calculate exposure time for star trail photography
Star Trail Settings
3h 0m
Total Exposure Time for 45° Arc
18 mm
Trail Length on Sensor
360
Frames (30s each)
Recommended Settings
f/2.8-4
Aperture
800-1600
ISO
30s
Per Frame (stacked)
1-2s
Interval Gap
Tips: Stars rotate 360° in 24 hours (15°/hour). For a full circle, you need ~24 hours. Use stacking method to avoid noise buildup and battery issues. Point toward Polaris (Northern Hemisphere) or Southern Cross for circular trails.