Chase the Light

What Chase the Light does

Chase the Light shows photographers where the sun is right now and when the light is about to change, for the place you are or any place you search. The Light Loop lays out the whole day as one 24-hour loop of its seven light phases — night, astronomical twilight, nautical twilight, blue hour, golden hour, civil twilight and soft light — with the start and end of every window and what each one is good for. Above it, the sun arc tracks the sun's altitude live, and the background shifts with the sky outside.

Alongside the light: current conditions and a 24-hour forecast strip, live satellite imagery for the Americas, Europe/Africa and Asia/Pacific, and a Lock Screen countdown that appears when you open the app within 45 minutes before a golden or blue hour, or during one, and follows the window until it ends.

The Apple Watch app is free. The Light Loop runs around the edge of the watch screen with the time to the next golden or blue hour, or your next alert, in the middle. Turn the Digital Crown on the second page to move through the day's phases with a shooting tip for each. The Light Loop joins the Smart Stack before and during golden and blue hour, and two complications — Next Event and the Light Ring — keep the next window on your watch face.

What Pro includes

Chase the Light Pro is a one-time purchase. No subscription, no ads. It adds:

• Light alerts on iPhone and Apple Watch: golden hour, blue hour, sunrise and sunset
• Lead times for travel: set how early each alert should reach you
• A Light Loop Live Activity that starts on its own before every golden and blue hour
• Your choice of weather source: Apple Weather, Open-Meteo or the National Weather Service

Everything else — the Light Loop and all seven phases, the sun arc, weather, satellite imagery, the Lock Screen countdown when you open the app around a window, and the full Apple Watch app with its complications — is free. Bought Pro on another iPhone? Settings › Restore Purchase.

Frequently asked questions

How do alerts work?

Alerts are part of Pro. Tap the Alerts capsule on the home screen (or open Settings) to switch on any of the four — golden hour, blue hour, sunrise, sunset — and set a lead time for each. Every alert is a notification scheduled on your iPhone for its next occurrence at your current location. The schedule is rebuilt whenever the app is open, so the times follow you when you travel. Allow notifications when iPhone asks; you can change that later in Settings › Notifications › Chase the Light.

I didn't get an alert.

Check that notifications are allowed for Chase the Light and that a Focus mode isn't holding them back. Then open the app once: alerts are computed for where you were the last time the app ran, and the capsule on the home screen shows the next one and its rule ("Sunrise · 30 min early"). If the capsule reads "Nothing in the next week", nothing is switched on.

The same alert reached my watch twice.

With Pro, the watch schedules its own alerts, and when your iPhone is locked iOS also forwards the iPhone's alert to the watch. Both can arrive. The next update sends each alert from one device only, with a switch on the watch for alerts of its own.

What does the watch app need?

Nothing to buy. The watch asks for its own location the first time it opens, and shows the loop, the countdown and the day's phases without the iPhone nearby. Pro is bought on the iPhone and reaches the watch over Apple's device link; if the watch's Alerts page still shows the Pro gate, open the iPhone app while the watch app is open.

When does the Lock Screen countdown appear?

Open the app within 45 minutes before a golden or blue hour, or during one, and the Light Loop appears on the Lock Screen and in the Dynamic Island. It counts to each change of light, follows the whole window on its own and says when it's over. With Pro it also starts by itself before every golden and blue hour, with a short alert as it begins. It ends when the window does.

Where does the weather come from?

Open-Meteo, a free global model, credited at the bottom of the Current Conditions card. Pro can choose Apple Weather or the National Weather Service (US locations) in Settings › Weather Source. If Apple Weather can't be reached, the app falls back to Open-Meteo and says so on the card.

Why does a time differ by a minute from another app?

Since 1.2.1, sunrise, sunset, solar noon and every light phase match NOAA's calculations to within a few seconds. Apps round differently, and some define the twilights at other sun angles.

How is my location used?

Only while the app is open, and separately on iPhone and on the watch. The sun position and the light phases are computed on the device. Your coordinates go to the weather source for its forecast and to Apple Maps for the place name and time zone, and nowhere else. No account, no analytics, no ads. The privacy policy has the detail.

Contact

Questions, bug reports and ideas are welcome. Write to chasethelight@ihaupt.com or reach out through github.com/Haupt2it. For a bug, include your iPhone or watch model and the version shown in Settings › About.