Long Exposure: Slow Shutter

Long exposure photography, without the guesswork.

An iPhone shutter physically cannot stay open for thirty seconds. So this app
does what a long exposure actually is: it stacks hundreds of live frames on the
GPU and blends them in linear light, the way the physics wants it done. The
result is a real long exposure — and you watch it form on screen while it
happens.


THREE WAYS TO STACK

Motion Blur — averages every frame into smooth, flowing movement. Waterfalls
turn to mist. Clouds smear across the sky. Crowds become ghosts.

Light Trail — keeps the brightest pixel from each frame. Headlights draw
ribbons through traffic, sparklers write in the air, stars arc across the night
sky.

Low Light — adds frames together to gather light a single shot could never
collect. The more frames land, the further noise falls away, and dark scenes
come back clean instead of grainy.


STOP WHEN IT LOOKS RIGHT

Most long exposure tools ask you to commit to a duration up front, then leave
you waiting blind. Here the exposure builds live in front of you. Watch the
trails grow, watch the water go silky, and end the shot the moment it looks
right.

Not there yet? Pick the exposure back up and keep stacking from exactly where
you left off. Nothing is thrown away until you say so.


TOOLS THAT TELL YOU THE TRUTH

• Live histogram that updates as the exposure builds
• Zebra clipping warning marks blown highlights before you lose them
• Running frame count and total exposure time, always on screen
• Review the finished frame full size before anything is saved


SEVEN SCENE PRESETS

Waterfall, Traffic, Star Trails, Fireworks, Light Painting, Night Scene, and
Empty the Street — the last one averages a busy scene until the people walking
through it simply disappear, leaving the street to itself.

Every preset is a starting point, not a cage. Adjust anything after loading one.


MANUAL CONTROL WHEN YOU WANT IT

• Lock exposure, white balance and focus so brightness and color never drift
mid-stack
• Manual ISO, or let the app work it out from the scene
• Set exposure length, or hold the shutter open and decide by eye
• 3 and 10 second self-timer for tripod work


BUILT PROPERLY

• 16-bit float accumulation, so nothing bands or clips partway through the stack
• sRGB is linearized before blending and re-encoded afterwards — highlights stay
honest instead of turning to grey mush
• Saved to your photo library as HEIC with real EXIF: total exposure time, ISO,
capture mode, and the exact number of frames stacked
• Full resolution. No watermark. No account.
• iPhone and iPad


WHAT IT IS GOOD AT

Silky waterfalls and coastlines. Car light trails on a night road. Star trails
and the Milky Way. Fireworks caught as complete bursts instead of fragments.
Writing in the air with a torch. City streets after dark, without pushing ISO
until the noise eats the shot. Clearing tourists out of a landmark photo.

A tripod or a steady surface will always give you the cleanest result — that is
true of every long exposure ever taken, on any camera.