Microcontroller-based DIY light meter

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Title: Microcontroller-based DIY light meter
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My Notes
--------
2026 Dec 5

### References

(1) search: diy pico light meter
    - there are lots of projects, many are for photography but not all
    - pico, arduino

(2) https://github.com/veebch/photon
    Photon: an open-source incident light meter
    Components:
    Raspberry Pi Pico (or Pico Lipo, so you don't need to add the separate power shim)
    OLED Screen (Waveshare 128x128 full colour)
    LiPo Power shim (Pimoroni LiPo Pico shim - only if you a using a Pi Pico)
    Rotary encoder (adjust settings and change priority mode) (example)
    Two momentary switches (1x keyboard switch and 1x 6x6mm microswitch to measure light and set iso adjust mode respectively)
    Light Sensor (Pimoroni BH1745)
    LiPo/LiIon battery


(3) https://www.diyphotography.net/the-photon-is-a-tiny-open-source-handheld-light-meter-powered-by-a-raspberry-pi-pico/

(4) https://www.veeb.ch/projects/light-meter-on-a-shoestring
    - intended as a photography light meter

(5) search: diy microcontroller light meter

(6) https://www.pishop.ca/search.php?search_query=bh1750&section=product
    Arduino Compatible Digital Light Sensor (BH1750FVI)
    $4.95  in stock
    This is a digital light sensor that can be used to precisely measure the ambient light level.
    The sensor has a 16 Bit AD converter so it outputs a digital signal that can be read using the Arduino's serial connections.
    It measures light to a similar level as the human eye so is great for home automation projects.
    It is very easy to implement into your project as an Arduino library for this sensor already exists.

    If you are looking for a way to make this sensor work then we have found this very good instructacble here that includes a link to a Library file.

    Key Features:
    Based on the BH1750FVI light intensity Sensor
    16 bit AD converter takes an analog signal and turns it into a digital signal
    Output is in LUX (a measure of light intensity)
    Input voltage 3.3 to 6 volts
    I2C bus Interface with 2 alternative address (f/s Mode Support)
    The sensor is very robust to interference from different light source types and infra-red light
    Sensor range: 0.11 Lux to 100,000 Lux

(7) https://www.instructables.com/BH1750-Digital-Light-Sensor/
    - recommended in ref[6]
    - uses Arduino

(8) https://www.elechouse.com/elechouse/images/product/Digital%20light%20Sensor/bh1750fvi-e.pdf
    datasheet recommended in ref[7]

(9) https://www.pishop.ca/product/arduino-compatible-analog-light-sensor/
    Arduino Compatible Analog Light Sensor, $2.95
    - uses an LDR ?

() https://shop.pimoroni.com/products/bh1745-luminance-and-colour-sensor-breakout?variant=12767599755347
    BH1745 Luminance and Colour Sensor Breakout by Pimoroni
    $16.28 CDN, out of stock

() https://www.pishop.ca/product/bh1745-luminance-and-colour-sensor-breakout/?searchid=0&search_query=BH1745
    BH1745 $15.95, in stock, Pimoroni

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