VBR-20 DLI Meter,Full Sun,Partial,Shade,Record Long Term Daily Light Integral,180 Days,MOL/m²/d,can be exported as a File

In contrast to the impression I got from descriptions and reviews, you do not need to keep the app open or the phone nearby for the light meter to work. It keeps recording while disconnected, and when you want to read the results, you push the button on the meter and then click in the app.Seems pretty similar in accuracy to the $300 one I had before this that died due to rainstorms (though I can’t directly compare them). This one so far hasn’t died from rain though I haven’t left it out in major storms.

If you shop around, you're not likely to find a DLI logger anywhere near this low price, and that makes it worth a look. It's simple enough to set up, and depends on an app to view the data. I've attached a screen shot from my unit, placed a few days ago in a partial/mostly shaded area in my San Diego backyard. Average December DLI for this area without shade, according to the "U.S. Daily Light Integral Map", is 20-25, so these numbers are plausible.To connect the app to the logger, you need to press the yellow button to start up bluetooth communications. You can then view the current collected data (as in my screen shot). The chart is useful and easy to scroll through; I'm not sure what the numbers and buttons below the graph are for.When you're not near the logger, you can use the "record" button on the Devices page to see the data collected in the past.Bottom line: for very little, this product gives you an easy way to see how much illumination you're getting from the sun or from indoor grow lamps. And there are plenty of resources online if you want to learn more about DLI and how it affects your garden.

If I could give zero stars I would. It would not even turn on. The tiny screwdriver would not catch the screws to turn them to take the back off and replace the battery.

Great and useful tool for finicky plants to monitor and adjust your dli.

It seemed like a good value but it has to remain connected to Bluetooth to get an accurate reading. Unfortunately the app kept crashing on ios for me so I was never able to get an accurate reading. I will continue to mess with it and update if I am able to get it to give me a proper reading.

This worked great for about two weeks. It was helpful in the information it gave me. Now the green light no longer comes on and I cannot connect to it to download any information. Wasn’t worth what I spent on it.

This VBR-20 DLI meter measures the daily light integral in the 400-700 nanometer wavelengths of light, which are the frequencies that plants use. It uses the DLI because it balances the length of day with the amount of photons (expressed in a meter squared). Other measurements are not as handy for growers because they either measure frequencies not useful to plants or don't factor in the day length.Set up is super easy. You load an app and connect via Bluetooth to the meter to get its data.UPDATE after 30 days: (see screenshot) I stuck this in a flower pot on our patio. As you can see, we're in deep shade. My max reading is around 2.3 but, to get partial shade, it needs to average above 4.I'll report back when I get enough data to share.

The unit was either unable to store information or connect to Bluetooth consistently or both. It did connect one time