How to Measure Light With Photone

Get started on measuring light with Photone

As a plant owner you’re interested in measuring the incident light on your plants’ leaves, which is what makes them thrive. Light impacting a surface is called light intensity (intensity = energy per unit area). Photone measures light intensity by using the camera as a light sensor.

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On your device, Photone is using the built-in ambient light sensor (ALS) to measure light intensity as a fallback.

How Photone Works

To measure light, Photone configures the camera in a specific way and takes many images in a row. An image is in fact nothing else than a representation of how much light has entered the camera lens and which colors of light were present at a given point in time. By analyzing the raw image and the corresponding meta data, Photone’s measurement algorithm can then calculate the current light intensity and color temperature.

Thus, the camera should always point at your light source so you measure incident light. By “filming” your plants the camera would measure light reflected by the plants. This is why Photone uses the front (selfie) camera and not one of the back cameras.

Place your device on the top of your plants’ canopy to measure the light they receive

How to Set up Photone

To use your device to measure light intensity with professional accuracy with Photone you need two things:

1. A Diffuser

Learn what a diffuser is and how easily you can get or build one by reading this guide:

2. Selecting the Light Source to Be Measured

Selecting the light source you're measuring allows the measurement algorithm to adapt and correct potential spectral mismatch errors. Check this guide to learn which setting to choose for your light:

To set up Photone you just need to select the light source you're measuring so that the measurement algorithm can correct potential spectral mismatch errors. Check this guide to learn which setting to choose for your light:

How to Take a Measurement

Taking a measurement is simple: First, select a measurement value by swiping left or right on the main screen. Then, place your device on top of your plants’ canopy.

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If you’re unable to read the measurement (e.g. because your light is too bright), press the lower part of the screen to HOLD the measurement.

Check the guide below to see all light measurement values and units that are available on Photone:

Need to Measure Under Water?

If you have an aquarium and want to measure light intensity inside the tank, check out the guide on underwater measurements:

Not Measuring What You Expect?

Measuring light can be a complex task. But don't worry, we've got you covered. Learn more about common mistakes and how to fix them:

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