Inside the app
A closer look.








About this app
Made for a clear purpose.
Lumen Forge is a field exposure workbench for photographers, cinematographers, gaffers, students, and anyone who wants reliable light and exposure math close at hand.
Use the camera-based meter to read scene luminance and color temperature, then move directly into exposure planning, ND selection, flash guide-number math, zone-system notes, saved lighting recipes, or the new Field Pack.
Core tools: - Live camera-based light meter - Lux, foot-candle, EV, ISO, shutter, and aperture readouts - Exposure triangle solver with equivalent exposure ladders - Color-temperature reference swatches for common lighting conditions - Zone-system histogram with shadow and highlight warnings - ND filter calculator for daylight long-exposure planning - Flash guide-number math with ISO scaling - Lighting recipe notebook with modifier, subject, and location notes - Side-by-side recipe compare - B&W filter factor calculator with Kelvin interpolation - Hyperfocal, cine shutter, sunny f/16, macro, polarizer, and star-trail helpers - Film reciprocity correction and AEB bracketing planner - Field Pack with readiness scoring, support/gels/ND/bracket guidance, copyable shot brief, and ten offline reference sheets
Lumen Forge keeps the workflow focused: meter the light, compare choices, save a useful note, and get back to shooting.
Lighting recipes and app settings stay on the device. Camera access is used only for the live meter and color-temperature features.