Max brightness & no sleep
Force the screen to maximum brightness and prevent it from sleeping while the meter is active.
Where to find it
Settings Theme Max brightness & no sleep
Summary
An opt-in toggle that pins the screen to maximum brightness AND adds FLAG_KEEP_SCREEN_ON so the device cannot dim or sleep while the metering camera is running. Used for outdoor metering in direct sunlight where auto-brightness would otherwise be unreadable. Two safety auto-releases protect a forgotten-on screen: a thermal monitor drops the lock when the system reports MODERATE heat, and an idle timer drops it after 15 minutes without user interaction.
Detail
How it works
What it does
Two things at once: it pins the screen to its maximum brightness (overriding the system's auto-brightness slider) and it tells Android to never let the screen sleep while the meter's camera is active. The combination keeps the viewfinder readable in direct sunlight and stops the device from dimming or locking mid-shot.
When to turn it on
Outdoor metering at midday, snow scenes, white-sand beaches, anywhere the ambient is brighter than your phone's auto-brightness ceiling. Also useful for long contemplative compositions where the device would otherwise drop the screen mid-decision.
Safety auto-release: device is warm
If Android reports the device has reached the MODERATE thermal state, the lock releases automatically and the system can dim and sleep the screen normally. A Toast tells you it happened. The lock re-engages on its own once the device cools back to NONE or LIGHT. This guards against thermal damage if the screen-on-max-brightness combination is left running in the sun.
Safety auto-release: app has been idle
If 15 minutes pass without any touch or key press while the app is in the foreground, the lock releases and the screen is allowed to sleep normally. A Toast announces it. Tapping anywhere on the screen counts as interaction and re-engages the lock within 30 seconds. The 15-minute window is long enough for a slow compose but short enough that a forgotten-on screen cannot drain or heat-soak the device unnoticed.
Pairs with Red Light
Red Light mode hard-disables this lock because darkroom and astrophotography work depends on the system brightness slider. If you turn Red Light on, the max-brightness toggle is ignored regardless of its setting and the system's brightness controls take over.
Battery impact
Max brightness is the single largest battery draw on a phone. Expect roughly 2x to 3x the drain of normal use while the lock is engaged. The auto-releases above mitigate the worst case but plan to top up the battery during long outdoor sessions or carry a power bank.