Quantum PAR Meter Full-Spectrum High Precision PPFD Tester for Photosynthetic Activity of Indoor and Outdoor Plants 400-700nm Light Lux Tester

Works good and seems to be accurate.

Appears to be well made and solid. It is simple to use with clear instructions. My prior PAR meter, which I paid $172 for was cheaply made and would not hold a charge. This model uses batteries which eliminates the cheap battery issue. So far I am very pleased with it.

Great purchase! Does what it was made to do! Pivotal in dialing in conditions in my grow tent! Affordable price is well worth it👍

A PAR meter is useful to know if plants are receiving enough light of the kind that they need. Using this has been very useful for adjusting grow lights and understanding when a grow light is needed. I am completely reliant on the claims of accuracy since I don't own an apogee meter to test it against. Maybe someone does and can report the results. But I'm happy with it and do recommend it if you aren't sure that your plants are getting enough light, or you are not getting the results you want with the lights you have. Use the PAR reading along with DLI (daily light integral) to adjust your light intensity or distance to your plants and how many hours the light must run for the plants you are growing. Different plants need different total amounts of usable light. There are websites and videos that cover PAR and DLI which are a good resource. Addendum: This is really intended for use with indoor or greenhouse lighting, not for outdoor use. It works fine outdoors, but outdoor light is very strong and there is seldom any need to measure that. This is very useful when growing or starting plants indoors, even in a greenhouse. Plants need a certain total amount of light each day. The PAR meter measures the INTENSITY of the light spectrum that is usable by plants. Intensity is one part of the equation. The other part is QUANTITY needed which is measured by DLI (daily light interval). That varies depending on the type of plant and even its stage of growth, if you want optimal results. Think of your plants needing a certain quantity of daily light. PAR indicates how fast the light is coming in, DLI shows the total amount of light needed. PAR x Hours of light = Quantity (DLI). Knowing the PAR allows you to calculate the number of hours that grow lights must be on to get the necessary DLI. I start plants early in the year in my starter greenhouse. The days are short so I must supplement the natural light with grow lights. Usually a PAR of 700 - 750 is sufficient for most plants over about 16 hours. During the day, natural light supplies a good portion, so I use a timer to turn the grow lights on early in the morning when it is dark, then off once the sun is strong enough, then back on in the afternoon as the sun dims, and then off for the day late at night. If you are growing indoors, then the lights would be on from early morning to late at night. A PAR meter is crucial to properly adjust your lighting. A PAR meter will quickly show the insufficiency of light coming in through a window for most plants.

Works as advertised. A very useful tool every indoor home grower should have. Knowing right where to put your light is a game changer. You spent money on the lights and you spend money on the electricity you would be remiss not to maximize the efficiency and get the most out of your grow.

I like it, definitely helps keeping my plants at consistent setting across brands of light. Showed me that my big box store lights were not cutting it

Very accurate right out of the box and fairly easy to use.

I purchased new led lighting system to start my vegetable seedlings and was unsure what distance to keep the lights for different varieties . This meter works great to measure how much light the seedlings are receiving at leaf level making sure they are r receiving enough light and not too much for proper growth.

Funktioniert extrem präzise und zeigt mir genau an ob alles stimmt oder nicht, bin sehr glücklich dass ich mich nicht mehr auf das dämliche Handy verlassen muss wo die Werte sowieso kaum stimmen wenn man nicht eine entsprechende teure Kamera hat.

It does its job, taking the guesswork out of providing the correct amount of light for my seedlings. Easy to use.

Amazingly accurate for the price.Have recommended it to a lot of other growers.

Pratique, fiable et pas trop cher !

Indispensabile per non improvvisare