Silverlog Stars

Calculate the longest exposure for sharp stars at any focal length. Avoid star trails with the 500 Rule, NPF Rule and more.

Silverlog Stars calculates the maximum exposure time for sharp, pinpoint stars — helping you avoid unwanted star trails in astrophotography.

HOW IT WORKS Enter your focal length and sensor/film format. The calculator shows your maximum shutter speed using multiple established rules (500 Rule, NPF Rule) so stars remain points of light rather than streaks.

FEATURES • 500 Rule calculation • NPF Rule calculation (more accurate for modern sensors) • Multiple sensor and film format support • Adjustable pixel pitch for precise NPF results • Star trail mode — calculate exposure for intentional trails • Works offline — no internet connection needed • Clean, focused interface • Dark mode support

USEFUL FOR • Milky Way photography • Nightscape and starscape shooting • Choosing the right focal length for astrophotography • Understanding the relationship between focal length and star movement • Planning intentional star trail exposures

Part of the Silverlog photography toolkit. No account required. No data collected.