In photography, an enlarger is a piece of equipment that projects a smaller image onto a photosensitive material below using a strong light source and a negative to produce a much larger print.And while these have historically relied on single-color incandescent bulbs, such as in the case of Redditor wgimbel’s Beseler 45, there are also models that can produce polychromatic projections for more accurate color reproduction.Because of this limitation, wgimbel sought to replace his Beseler 45’s lamp with an Arduino-based system and several LEDs.
Responsible for acting as the light source, this project utilizes a total of 40 RGBW LEDs on the Adafruit NeoPixel Shield.They, in turn, are connected to an Arduino Nano ESP32 via a level shifter along with a 75W power source for the full range of brightness.In addition to producing far less heat due to their reduced energy consumption compared to a traditional lamp, these RGBW LEDs can output a wide range of colors over time for very fine-tuned control over the image’s final appearance.
The last component in this enlarger upgrade is the use of an Arduino GIGA WiFi R1 + GIGA Display Shield to let wgimbel input the brightness, grading, color values, and more through an easy-to-use interface.Selecting ‘Start’ or touching the foot pedal will initiate the timer and communicate the values to the ESP32 over BLE.To read more about this project, you can check out wgimbel’s post here on Reddit.
