LumenLab vs Light Meter

LumenLab is 100% software, using your iPhone's built-in camera — no external hardware required. LumenLab turns your iPhone's rear camera into a real-time light meter. By reading the camera's exposure metrics (ISO, shutter, aperture), it computes the illuminance of your environment in lux — perfect for photographers, plant growers, interior designers, and anyone who cares about lighting. KEY FEATURES • Real-time lux reading using camera exposure parameters • Color-coded zones: dark · dim · normal · bright · glaring • Lighting recommendations for each level • One-tap session reset • Core measurement works offline — no tracking, no ads, no account USE CASES • Photographers checking ambient light levels • Cinematographers metering scene illumination • Plant growers ensuring grow-light intensity • Interior designers checking room brightness • Office ergonomics (recommended 300–500 lux) • Reading nook brightness check PRO FEATURES (optional subscription) • Advanced metrics row: EV, ISO, Shutter, Aperture (f/) • Session statistics: minimum, average, maximum lux • Calibration multiplier to align with a professional reference meter • CSV export of full session log (timestamp, lux, EV, calibration factor) • Zero ads forever HOW IT WORKS LumenLab opens the camera (no recording, no preview saved), reads the device's auto-exposure metrics every frame, and applies the photographic equation: EV = log₂(N²/t) − log₂(S/100) lux ≈ 2.5 × 2^EV × calibration This is a practical camera-exposure estimate. For critical comparisons, calibrate against a known light source or reference meter. LIMITATIONS The iPhone camera is not a calibrated photometer. Readings are estimates and can vary by device, lens, scene reflectance, and auto-exposure behavior. Not suitable for regulatory, lab, or safety measurements. PRIVACY The camera is opened only to read auto-exposure metadata. No images, video, or audio are recorded, saved, or transmitted. No analytics, no ads, no account. StoreKit is used only for the optional Pro subscription. SUBSCRIPTION INFO • Payment will be charged to your Apple ID account at confirmation of purchase. • Subscription automatically renews unless auto-renew is turned off at least 24 hours before the end of the current period. • Your account will be charged for renewal within 24 hours prior to the end of the current period. • You can manage and cancel your subscriptions by going to App Store → Account → Subscriptions. Privacy Policy: https://frexx.top/lumenlab/privacy.html Terms of Use: https://frexx.top/lumenlab/terms.html SUPPORT jie.xiang.jm@gmail.com

Light Meter helps you measure exposure in real time and find the right camera settings faster. Designed for photographers and filmmakers, the app turns your iPhone into a practical exposure meter for everyday shoots, studio work, portraits, landscapes, and low-light scenes. Quickly read the light in front of you, lock the settings you want to keep fixed, and let the app calculate the missing exposure value automatically. Whether you are shooting with a digital camera, film camera, cinema camera, or manual lens, Light Meter helps you work with more confidence before you press the shutter. • Live Exposure Reading Measure light in real time and instantly calculate camera-ready exposure settings. • Lock Any Two Controls Choose which two settings stay fixed - ISO, shutter speed, or aperture - and let the meter calculate the third automatically. • Shutter Priority Freeze motion or create blur while the app calculates the right aperture. • Aperture Priority Set your depth of field and let the meter solve the matching shutter speed. • Auto ISO Keep shutter speed and aperture fixed while the meter adjusts ISO automatically. • Spot Metering Tap the preview to meter a specific part of the scene with more precision. • Built for Real Shoots Use it for portraits, landscapes, studio lighting, street photography, film photography, and video exposure planning. Light Meter gives you a fast, visual way to understand exposure before shooting. It is especially useful when working with manual cameras, adapting to changing light, checking mixed scenes, or planning a consistent exposure setup. Simple enough for beginners, precise enough for advanced photographers. Terms of Use: https://www.optionalchaining.com/terms-of-use Privacy Policy: https://www.optionalchaining.com/privacy-policy