AstroExposure vs Stopwise

AstroExposure is a simple, precise calculator for planning your night sky photography. Choose your calculation method, enter your focal length, aperture, and sensor specifications, and instantly get a recommended exposure time to minimize star trailing. The app supports the most widely used astrophotography rules, including the 500 Rule and the NPF Rule. You can also select a camera from the built-in database, adjust settings manually, and save your favorite configurations. Key features: • Astrophotography exposure time calculation • 500 Rule and NPF Rule support • Sensor or camera selection • Focal length, aperture, and pixel size settings • Favorites for quick access to your settings • Clean, fast, and distraction-free interface AstroExposure is designed for photographers who want to spend less time calculating and more time under the stars.

Stopwise is not a light meter — it is an exposure calculator. It does not use your camera or any light sensor. You enter what you already know — an EV value, or an existing aperture / shutter / ISO combination — and it works out the equivalent settings. Because it only does the maths, the result never depends on your lens, sensor or OS version. Fully offline, no network needed. ■ How it works Three dials: aperture, shutter, ISO. Each row has a lock on the right. ・One locked — turn either open dial and the other compensates. The EV stays the same. This is equivalent-exposure conversion. ・Two locked — only one dial is left; turning it changes the EV. Use this to derive EV from a known combination. ■ Accurate by design Labels like f/11 and 1/125 are photographic conventions, not exact values — f/11 is really 11.3137, and 1/125 is really 1/128. Stopwise always calculates with exact powers of two and only rounds for display. That makes it more precise than mental arithmetic or a printed table. ■ Free version ・Aperture f1.4 – f22 ・Shutter 120" – 1/4000 ・ISO 100 – 1000 ・1/3-stop increments ・The complete conversion engine and locking behaviour The maths is identical in both versions. The free version is not crippled. ■ Pro (one-time purchase) ・Aperture extended to f0.8 – f56 ・Shutter extended to 300" – 1/8000 ・ISO extended to 32 – 102400 ・Switch between 1/2 and 1/3 stops ・12 built-in scenes — pick one to set the EV directly ・Save up to 20 of your own scenes No subscription, no ads, no data collection. ■ Privacy Stopwise collects, stores and transmits nothing. No accounts, no analytics, no ad SDKs, and no permission requests at all.