Set up your plants’ lighting with a proper PAR light meter.
Photone (previously named Korona) is the light meter app that allows you to take all the
light measurements relevant for your plants and for all widely used grow light technologies.
PAR / PPFD in µmol/m²/s
DLI in mol/m²/d
Illuminance in lux and foot-candle
Light temperature in Kelvin
Built for Grow Lights
We actively develop, test, and optimize for the widely used grow lights in the market.
No Costly Equipment
Photone only requires your smartphone’s camera — nothing else.
Tailored to Plants
Measure PAR in µmol/m²/s and even calculate your plant’s DLI at the palm of your hand.
Compared to various common hardware light meters, Photone is repeatedly achieving the lowest average error rates in measuring grow light illuminance.
More information regarding measurement and evaluation details on the above error rates can be found in our white paper.White Paper
Reviews and Mentions
Comparison to Apogee SQ-500 PAR Sensor
Comparison to Apogee MQ-500 PAR Meter
by Growing Answers
Comparison to Apogee SQ-120 Underwater PAR Sensor
Identify where and how high to hang your lamp
Your grow light is a massive investment and draws a lot of energy. Get the most out of your light by positioning it in a way that it causes the healthiest plants and biggest yield possible.
Identify which area you want to cover with your grow light. Your goal is to provide an even and intense spread of light over this area. By measuring the PPFD in specific locations such as the center and the periphery you can then adjust the light spread to be as balanced as possible.
We have written in more detail about this topic in an article on our blog.
Duration and Power
Regulate how long and how strong your lights are on
Running a high power grow light for 24 hours can easily cost upwards of three dollars. Reducing the time and power as much as possible therefore directly reduces the energy bill significantly.
Identify the daily amount of light your plant needs. Then measure the daily light integral (DLI) using the Photone app. By increasing or decreasing the specified time on the app, you can then identify your ideal lighting duration. If your duration must be fixed, your other variable is power by dimming or positioning.
Our article further explains the daily light integral. To simplify the calculation, we put all of this into our handy calculator.
Identify when a light bulb needs to get replaced or cleaned
Depending on the grow light technology, the light output depreciates over the lifespan of the bulb. However, the energy consumption stays the same and the light gets less and less efficient.
Whenever you use a new light bulb, take an initial PPFD meausurement and note the value along with the date. Then take the same measurement in the same spot every few weeks of using the grow light. If the measured PPFD value is considerably less than the initial measurement, consider to clean or replace the bulb.
Our article further explains why grow lights produce less light output over time.