Lumu Light Meter vs LightScope

The light metering tool for every great image maker. Use the standalone app as a reflective light meter or use it in combination with Lumu Power hardware for professional Flash and Color Temperature measurements. Lumu Power is an easy-to-use digital incident color and light meter that works seamlessly with the free Lumu app to deliver Color Temperature, Illuminance, Spot, Ambient, and Flash Exposure metering functionality on your iPhone. A new expression of what a light meter can be, Lumu meets the needs of enthusiasts, professionals, and students who find existing light metering solutions too bulky, expensive, and complicated. “The Lumu Power is without any doubt the most full featured light meter I have ever owned. It’s tiny, it weighs hardly anything, it manages to offer a feature set that expands way beyond what most will ever need from such a device.” - www.35mmc.com Key features: - SPOT METERING: Use your phone’s camera as a reflective light meter. With Lumu Power: - PHOTO SINGLE mode: Giving you exact parameters: exposure time, f-number, ISO, EV, lux. - PHOTO MULTI mode: Calculating average value or contrast between multiple measurements. - PHOTO PINHOLE mode: Measuring exposure time for custom pinhole camera settings. - CINE/VIDEO mode: Set FPS, F-number, exposure time and ISO. Get the values for the ambiental light. - FLASH EXPOSURE: See the graph of flash duration, measure its intensity. - COLOR TEMPERATURE: Read light Color temperature in Kelvin and Green/Magenta shift. - CHROMATICITY: See light colour in CIE1931 diagram and get X,Y,Z coordinates. - ILLUMINANCE mode: showing incident light level in lux / foot-candle values. - NOTES: Store all your measurements together with geo-location, custom notes and your photo in one place. + ND FILTERS, EXPOSURE COMPENSATION and more… Visit http://lu.mu/ to learn more.

LightScope is a comprehensive solution providing professional light measurement and analysis using your iOS device's camera sensor. 【Key Measurement Features】 • Illuminance (lux) Measurement: Calculates accurate illuminance by analyzing EXIF data from the camera sensor. Illuminance is derived using the formula: (F-number² / (Exposure Time × ISO)) × Calibration Factor. • Exposure (EV) Calculator: Converts measured illuminance to EV and suggests proper exposure combinations in standard stops for your ISO and aperture (or shutter) settings. • Luminous Intensity (candela) Calculation: Automatically calculates the luminous intensity of a light source based on the set distance. Uses the formula: Illuminance (lux) × Distance². • Color Temperature (K) & Tint Analysis: Precisely measures the light source's color temperature (1500K~15000K) and tint (green-magenta bias) by analyzing the camera's white balance sensor data — useful for identifying fluorescent and LED lighting. • Real-time Histogram: Visualizes the balance of shadows, midtones, and highlights through 16-level brightness distribution analysis. • Contrast Ratio Measurement: Evaluates the brightness ratio between bright and dark areas of a scene (based on 10th/90th percentiles) according to WCAG accessibility standards. • Noise Measurement (SNR): Calculates the signal-to-noise ratio in dB to evaluate image quality in the shooting environment. 【Advanced Features】 • Image Capture and Storage: Captures camera images at the time of measurement and stores them with measurement data. • Full-screen Image View: Zoom, pan, and rotate captured images for detailed inspection. • Gallery Saving: Save captured images to your device's photo library. • Measurement History and Trends: Save all measurements chronologically and chart trends for lux, EV, color temperature, contrast, and SNR. • Continuous Logging: Automatically record measurements at a set interval (1-60s) — great for lighting design and site surveys. • Full-Resolution Image Storage: Keep captured images at original quality for detailed inspection and gallery saving. • Export All History: Export every measurement as a CSV file or a PDF report. • Notes & Location Tags: Attach notes to measurements and optionally save the measurement location. • Home Screen Widget: See your last measurement (lux, color temperature, contrast, SNR) right on the home screen. • Camera Full-screen Mode: Hide panels to focus on the camera view while checking key measurements via a mini info panel. • Measurement Lock: Freeze exposure and white balance for stable, steady readings. • Spot Metering: In full-screen mode, tap anywhere to meter around that point. • Perfect Dark/Light Mode Support: All UI elements automatically adapt to the system theme. 【User Settings】 • Calibration Wizard: Enter a reading from a reference lux meter and the calibration factor is calculated automatically. Manual slider adjustment is also available. • Distance Setting: Set the distance to the light source for precise luminous intensity (cd) calculations. • Front/Rear Camera Selection: Choose the appropriate camera for your measurement situation. 【Technical Features】 • Support for measuring various light source types: natural light, LED, fluorescent, incandescent, etc. • Color temperature and tint sourced directly from the camera ISP's white balance estimation for reliable readings • 10-frame moving average filter for measurement stabilization • Center-weighted or spot (tap-to-meter) analysis for accurate evaluation of the main subject • Automatic exposure quality assessment based on histogram analysis Perfect tool for photographers, videographers, lighting designers, UI/UX developers, and anyone who needs accurate light measurements.