Grow Light Theory

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Far-Red 730 nm: Why It's Added to Grow Lights and How Much You Actually Need

Far-red light (730 nm): why it is added to grow lights and the required amount. The Emerson effect,…

02 Aug 2026 Read →

How Much Light Does the Sun Give: PPFD and DLI by Latitude, Season and Cloud Cover — With a Visual Simulator

Supplemental seedling light in winter? Interactive widget and light calculator: PPFD and daily dose…

29 Jul 2026 Read →

PPFD Calculator: How to Convert Lux to PPFD by Lamp Spectrum

A lux meter costs pennies; a quantum meter costs hundreds. Our PPFD calculator turns any lux meter …

22 Jul 2026 Read →

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DIY, Lighting and Electrical

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PPFD & PAR Map Simulator for Grow Tents

PPFD calculator for grow tents: build a PAR map grid, check coverage and uniformity, read the PPFD…

19 Aug 2026 Read →

Lighting Calculator: Lux, Uniformity and Glare to EN 12464-1

Room illuminance calculator: lux, UGR, and W/m² according to EN 12464-1. Calculate the number of lu…

18 Aug 2026 Read →

SunLike LED Spectrum Mixer: The Perfect Custom Light for Duv

How to properly mix SunLike LEDs, avoiding DUV and MacAdam step errors. A review of the SunLike LED…

16 Aug 2026 Read →

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LED news

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What's really soldered onto your Quantum boards from AliExpress? Samsung LED's exit from the LED market

Samsung has officially ended production of the LM301H EVO and the entire LM301 line — the last ship…

28 Jul 2026 Read →

Review of the new Seoul SZDR5A0G phytoLED: 660nm evolution and comparison with the Osram Osconiq GH PUBRA1.25

A detailed review of the new Seoul SZDR5A0G (660 nm Deep Red S1CH-3535660002-0000000) LED for plant…

21 Jul 2026 Read →

Acrich technology from Seoul Semiconductor or LEDs 220 volt

The History of Acrich Technology from Seoul Semiconductor. Direct-on-Board (DOB) AC LED Matrices: D…

02 Jul 2026 Read →

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Electronics, equipment and smart lighting

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How to calculate resistors in series and parallel - formules and calculator

Resistors in series and parallel: formulas, resistance calculation, and a series parallel resistor …

03 Sep 2026 Read →

Resistive voltage divider — calculator, formula and calculation

Voltage divider calculator & formula. Free resistor divider tool — enter values (1kΩ–100kΩ) to calc…

31 Aug 2026 Read →

LED Resistor Calculation: Theory and Formulas

Complete guide to LED current limiting resistor. Learn manual LED resistor calculation & how to cho…

30 Aug 2026 Read →

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Electricity and solar energy

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How to Choose a Circuit Breaker: Rating, B, C or D Curve and Sizing by Power

A breaker protects the cable, not the load. The coordination rule, what separates B, C and D curves…

04 Aug 2026 Read →

Solar Panel Output Calculator: Accurate PV Generation, Payback & Tilt Angle

Accurate solar panel output calculator. Estimate annual PV generation, optimum tilt angle, and payb…

03 Aug 2026 Read →

Wire Gauge & Voltage Drop Calculator: AC/DC, Single & Three Phase

Online wire gauge and voltage drop calculator. Convert AWG to mm², calculate size for AC/DC, 1 and …

02 Aug 2026 Read →

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Industrial and domestic LED lighting

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Melanopic EDI Calculator: How Much Blue Light Before Bed Is Too Much

Turn lux into melanopic EDI for any lamp spectrum: the 250 lx daytime target, how much blue light b…

20 Sep 2026 Read →

How Does an Integrating Sphere Work: Working Principle & Calibration Procedure

Learn what an integrating sphere is used for and exactly how it works. Interactive 3D widget, theor…

09 Sep 2026 Read →

CQS Color Quality Scale: Differences from CRI in LED Lighting

Explore the CQS Color Quality Scale and its benefits for CQS LED lighting. Learn how the color qual…

29 Aug 2026 Read →

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