Normally speaking, LED flashlights’ color temperature can be divided into white light (about 6500K color temperature), neutral white (about 4000k) and warm white(about 3000K).
Why do we have to make such division ? To answer such question, we need to know about what is called “color rendering”. Color rendering, expressed as a rating from 0 to 100 on the Color Rendering Index (CRI), describes how a light source makes the color of an object appear to human eyes and how well subtle variations in color shades are revealed. The higher the CRI rating is, the better its color rendering ability. A high-performance white-light LED flashlight’s CRI is about 75 %( higher the color temperature, lower the CRI), while good neutral white flashlight and warm-white flashlights’ CRI are about 80%.
What are these figures meant for us? For instance, in wildness, strong light flashlight’s brightness is high enough to identify subjects’ contour, but subjects’ details and gradation need good CRI to recognize. That is to say “Brightness” alone can help identify subject contour. But when it comes to judging subjects’ color, details and gradation, it requires a minimum CRI of 75% (If visual interference and adaptation excluded, 135% is needed.) to take on a 100% color rendering light source’s detail effect. That’s why we always pursue a higher CRI.
The illumination principles of white light LED goes like this: electron goes through chips to emit blue light, and then it excites fluorescent powder to emit yellow light, finally the two light combined into white lights. Yellow light ‘s CRI is higher than blue light, therefore to raise the proportion of yellow light can lift CRI.From this angle, the warmer the light color, the higher the CRI and more suitable for outdoor sports. Besides, warm light’s low color temperature and long wavelength allowing it further penetration ability in rainy and foggy weather. That’s why outdoor sports requires warm color LED flashlight.
On the other side, the efficiency of excited fluorescence is very low, warm white light’s total brightness will be much lower with a more dim light color. The beam will “dye” the projected subjects as if it is illuminated by small-power incandescent lamp. Comprehensively speaking, neutral white light LED products are the right choice for outdoor sports which has not only satisfying color rendering and penetration ability, but also avoid serious brightness decrease and dying problem.