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ESP-Meter

2025 · ESP32 · Film · Metering

ESP Meter is a compact exposure tool I built for film photography, using an ESP32 C3, BH1750 sensor, and a low power OLED interface.

Background

ESP Meter is a personal project for analog photographers who want clearer exposure decisions, especially when learning how aperture and shutter speed interact. It is built around an ESP32-C3, a BH1750 ambient light sensor, rotary encoders, switches, and a small OLED display to keep power use low.

Calibration

I calibrated the meter against a Sekonic L-308S, a common incident meter priced around $300. In testing, ESP Meter tracked within roughly 98% of the Sekonic EV readings. Total parts cost is about $15, which is dramatically cheaper while still accurate enough for day to day film shooting.