Zachary Marlow loves testing water and has a special interest in his hometown Lake of the Ozarks. Although he already owns a spectrometer, a photometer was out of his price range. So, like any good hacker, he decided to make his own and has posted a research note on Public Lab’s site. Using a 3D printer he made a box container to house an Arduino Nano, Adafruit’s GA1A12S202 light sensor, a cuvette and a dollar store laser. The laser turned out to be an interesting challenge.
This a part of the project I was worried about; I was afraid it was going to increase the cost above my goal. To get around this issue I found a pet laser for sale at Dollar General, but I knew aligning a laser with the sensor would add to the results changing too often and the data wouldn’t be constant. To solve this, I found that removing the lens of the laser made the laser act more like a red diode, which didn’t need to be aligned.
Zachary is studying Environment Management and Assessment /Biology, so he definitely has an interest in data. Here’s his hopes for his photometer.
My guess is that people will use it for what it’s designed for and test for turbidity or clarity of water, or combine these results with their spectrometer’s results to find true issues. I know certain construction industries and mining industries create a lot of these issues, and if we can eliminate some of these that would be great to see.
If you have an interest in a DIY photometer, make sure to check out Zachary’s project and give him a follow on Twitter @programmer1200. Testing water samples could be a great citizen science activity for a hike or camping trip!