Resolved: Brightness of white v blue bullets

[Gordy]

Have you done any comparisons with the blue compared with white bullets, measured in Lumens, Lux, Foot/candles(all illuminance)  or Foot/ lamberts (luminance)? I want to buy the maximum visibility in daylight running.

[Fluke]

Hi

The LEDs we use are the same for different colours (twin chip and same manufacturer), though the White units appear to the eye to give out more light simply because white light appears stronger and the UV reactive lens spreads the light out more evenly.

On our light meter both Blue and White give out the same actual light output.... we measure in Lux, and though this is not the best measurement ,accurate Lumens levels are hard to measure without very expensive equipment.

Measuring with a simple Lux meter gives us a good comparative reading.

As a comparison, a standard 5 watt car sidelight bulb produces a reading of 20,000 Lux on our meter, and a White / Blue BikeVis LED approx 80,000. Though some of that difference is attributed the Omni-directional nature of a normal filament bulb, the visible difference stands out to the eye.

We would recommend white simply because on a overcast day and lower light conditions they really stand out and also give a very slight blue tint which helps with night visibility.


The ideal bright daylight running light would consume a lot of power, probably too much for a normal motorcycle electrical system, but with our lights we feel we strike a happy compromise on power draw vs brightness vs size vs cost. I have two sets on my bike and would not ride anymore without them, they really help me especially on overcast days / evenings. At night they are VERY striking, producing much more visible light than a normal sidelight bulb. Remember the bulb we use was designed as a car sidelight upgrade.

Here is some comparative Lux measurements...

10-5 lux Light from Sirius, the brightest star in the night sky[2]
10-4 lux Total starlight, overcast sky[2]
0.002 lux Moonless clear night sky with airglow[2]
0.01 lux Quarter moon
0.27 lux Full moon on a clear night[2][3]
1 lux Full moon overhead at tropical latitudes[4]
3.4 lux Dark limit of civil twilight under a clear sky[5]
50 lux Family living room[6]
80 lux Hallway/toilet[7]
100 lux Very dark overcast day[2]
320?500 lux Office lighting[8][9][10]
400 lux Sunrise or sunset on a clear day.
1,000 lux Overcast day[2]; typical TV studio lighting
10,000?25,000 lux Full daylight (not direct sun)[2]
32,000?130,000 lux Direct sunlight

You can clearly see that full bright sunlight requires a lot to 'overcome'

The very best bright daylight running light would be HID based. But cost, power draw and size are far from ideal.