Lens Pattern vs Light Meter

Grid Professional Test Patterns for Camera Calibration Turn your iPad, iPhone, or Apple TV into a precision test pattern generator for camera and lens analysis. Lens Pattern displays pixel-accurate test charts directly on your device screen — no printed charts, no extra hardware. Perfect for camera calibration, lens quality testing, color grading verification, and production monitoring. INCLUDED TEST PATTERNS: Markers & Calibration • Grid Tags — AprilTag marker grid with adjustable tag size and start ID, ideal for camera calibration and spatial tracking Color & Exposure • SMPTE Bars — Standard SMPTE EG-1-1990 color bars • SMPTE 303M — HD color bars with PLUGE and Y-ramp zones • EBU Bars — EBU Tech 3325 color bars (75% and 100%) • ColorChecker — Classic 24-patch color reference chart • Color Scales — R/G/B/C/M/Y/W gradient ramps with percentage markers • Clipping — Shadow and highlight clipping test (1% steps) with stepped ramp • Grayscale — 21-step grayscale ramp with percentage labels Geometry & Focus • Crosshatch — Grid pattern for distortion analysis • Checkerboard — Black/white checkerboard for resolution testing • Caro — Diamond pattern (45° rotated checkerboard) • Dot Grid — Uniform dot array for distortion measurement • Siemens Star — Resolution target for sharpness evaluation • Focus Chart — Comprehensive focus and resolution target Timing & Animation • Motion Test — Moving bars for rolling shutter and motion blur analysis • Timecode — Real-time HH:MM:SS:FF display at 60fps • Flicker — Adjustable frequency flicker (0.5–30 Hz) KEY FEATURES: • Full-screen, pixel-perfect rendering on any screen size • Physical dimensions in millimeters displayed on iOS devices

Turn your iPhone into a real photographic light meter. Point the camera at any scene and read its exposure value (EV) and illuminance in lux instantly, then dial in the exact aperture, shutter and ISO for a perfectly exposed frame. Most "light meter" apps just show a brightness bar. This one does the math a classic handheld meter does: it reads the light your camera actually sees, smooths it in real time, and solves the full exposure triangle so you walk away with real camera settings, not a guess. WHAT YOU GET - A live EV and lux readout that reacts the instant the light changes - The exact aperture, shutter and ISO to expose any scene correctly - An exposure solver: lock any setting and get the others worked out for you - ND filter and long-exposure times so moving water and clouds go silky - Scene presets from Sunny 16 to candlelight and star trails for instant reference - Saved readings that keep EV, lux and full settings so you can revisit any scene PERFECT FOR - Film and analog shooters metering by hand with no in-camera meter - DSLR and mirrorless photographers double-checking tricky light - Long-exposure and landscape shooters stacking ND filters - Students learning how aperture, shutter, ISO and the Sunny 16 rule work WHY NOT JUST USE YOUR CAMERA'S METER? Your camera meters through the lens and averages the whole frame, so it gets fooled by snow, backlight and shade. This gives you an independent EV reading you can trust, plus ND and long-exposure math your camera will never do, and it calibrates to your gear so the numbers match what you actually shoot. PRIVACY The camera is used only to measure light on your device. Nothing is recorded, uploaded or shared, no account is required, and your saved readings stay on your iPhone. FULL ACCESS The live meter and the Learn guides are free. Full Access unlocks the exposure solver, scene presets, the ND long-exposure calculator, and unlimited saved readings: - Weekly - Yearly (best value) - Lifetime (one-time purchase) Point your phone at the light and read your next perfect exposure. Terms of Use (EULA): https://web-levi.web.app/terms Privacy Policy: https://web-levi.web.app/privacy-policy Questions? tphuc.work@gmail.com