Silverlog Stars
Astrophotography Exposure Calc
Free · In‑App Purchases · Designed for iPad. Not verified for macOS.
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.
Ratings & Reviews
- This app hasn’t received enough ratings or reviews to display an overview.
The developer, Simon Westgate, indicated that the app’s privacy practices may include handling of data as described below. For more information, see the developer’s privacy policy .
Data Not Collected
The developer does not collect any data from this app.
Accessibility
The developer has not yet indicated which accessibility features this app supports. Learn More
Information
- Seller
- Simon Westgate
- Size
- 28.6 MB
- Category
- Photo & Video
- Compatibility
Requires iOS 15.1 or later.
- iPhone
Requires iOS 15.1 or later. - iPad
Requires iPadOS 15.1 or later. - iPod touch
Requires iOS 15.1 or later. - Mac
Requires macOS 12.0 or later and a Mac with Apple M1 chip or later. - Apple Vision
Requires visionOS 1.0 or later.
- iPhone
- Languages
- English
- Age Rating
4+
- 4+
- In-App Purchases
Yes
- Actual Saint $29.99
- Guardian Angel $9.99
- Absolute Hero $4.99
- Nice One $0.99
- Legend $2.99
- Copyright
- © SilverLog 2026