Application Note AN108 Comparing Grow Lights

High-Wattage Special-Purpose Lamps A Comparison of Halogen, Compact-Fluorescent (CFL), High Pressure Sodium (HPS) and LED Lamps In High-Performance Photographic and Grow-light Applications.

Some Things Many Users Do Not Know

    Most professional photographers are familiar with terms like Lumens, Lumens-Per-Watt, Lux, Foot-Candles, etc. Likewise, they are aware of the transition from incandescent and halogen (which is just a slightly more efficient version of regular incandescent) toward Compact Fluorescent Lamps (CFL) and LEDs. They also know that reflectors can significantly increase the amount of light directed toward a subject or scene.

Similarly, those involved non-photographic markets, such as indoor growing, know that HighPressure-Sodium lamps (HPS) are still dominant in many global indoor-farming markets because of low cost and seeming very high efficiency.

What many users do not know is that things are not always as they seem--- or as promoted. Let’s walk through some of these often-misunderstood areas.

What is the meaning of the Lumens rating of a photographic light source...or the PPF rating of a grow-light ? (They both mean “almost” the same thing but in different language suited to the way used. Let’s talk about the four most common light sources which today have a “lumen” or PPF Specifications:

1. Incandescent lamp (including halogen type).

2. CFL lamp

3. HID lamps (Including High Pressure Sodium and Metal Halide Types)

4. LED chip. The chip, as purchased, is still not usable to a photographer, It must be put into an additional component assembly by another company or assembly line before it can be called a screw-in “lamp”.