Sunny16 Slider

Shooting film or a camera without a working light meter? Sunny16 Slider puts the classic "sunny 16" rule on a slide rule you can actually drag. The rule: in bright sun, set f/16 and a shutter speed of 1 over your ISO. Every step dimmer (hazy, cloudy, heavy overcast, open shade) opens up one stop. Sunny16 Slider does that math for you, and shows every equivalent exposure at a glance. HOW IT WORKS • Pick the light: tap the weather pill and choose Snow, Sunny, Hazy, Cloudy, Heavy or Shade, each described by what the shadows look like. • Slide the scales: ISO, aperture and shutter speed are horizontal scales. The aperture and shutter scales sit on top of each other like a real slide rule, so every aperture lines up with its matching shutter speed. • Set two, get the third: tap SET on any scale to make it AUTO. Auto shutter works like aperture priority, auto aperture like shutter priority, and auto ISO tells you which film to load for the shot you want. • Know your limits: shutter speeds too slow to hand-hold are flagged orange, and anything a camera can't do (faster than 1/8000, beyond f/45, outside ISO 25–6400) turns red. OPTIONAL: WEATHER AT YOUR LOCATION Not sure whether it counts as "hazy" or "cloudy"? Tap "Use weather at my location" and Sunny16 Slider compares the sunlight measured near you with a clear sky at the same sun height, then picks the matching step. It also accounts for a low sun near sunset and for snow on the ground. Location is only used when you turn this on, is rounded to about 1 km, and is never stored by us. ALSO • Exposure compensation from −3 to +3 stops, for backlit or deliberately dark scenes • Pinch or tap to zoom the slide rule • No account, no ads, no tracking • Works on iPhone and iPad Weather data by Open-Meteo.com.