Sunday, August 27, 2006

Seeing the Light

This is the first of hopefully many blog’s and ramblings I will be posting on the PAC Tour website. There will not be any planned schedule or agenda to these pages, but I may keep you posted of current events that are happening during a tour for example. It could also happen that some recent event may remind me of a past related story from 20 years ago that I decided to write about. Either way, I promise I won’t be writing just to fill up page space but I can’t guarantee everything I write will be that interesting or insightful.

Seeing the Light of Bicycle Lights
Susan and I were getting ready for Brevet Week next May. As we were writing the guidelines for the week we wanted to include something about bike lighting standards. I decided to order a selection of different battery lights and do a comparison test between them.

I ordered five small lights. These are all small enough to fit in your hand with batteries included. These are not lights with separate battery packs. I know there are some great lights with water bottle size battery packs that will last all night with a bright LED light. This light test was more to establish lighting minimum standards. Some of what I found out might apply to other high powered LED lights as well.

These are the lights I tested.

Cat-Eye HL-EL 400 OptiCube LED $29
runs for 80 hours on 3-AAA batteries

Cat-Eye HL-EL 300 Opticube LED $29
runs for 30 hours on 4-AA batteries

Cat-Eye HL-EL 510 LED $45
runs for 30 hours on 4-AA

Cat-Eye HL 500 Halogen $19
runs for 3 hours on 4-AA

ACE Hardware LED Flashlight $10
runs for 15 hours on 3-AAA

I did a simple test on a pitch black night in my driveway. I stood 100 feet from my garage door and places a 24 inch x 6 inch white sign with 4 inch red lettering on the garage door. At a height of three feet above the ground I shown each light at the door and tried to read the lettering on the sign.

The Cat-Eye 400 has the longest battery life, but the poorest illumination. The sign was barely visible at 100 feet except for a medium reflection from the sign and a 20 foot wide beam pattern.

The Cat-Eye 300 was next best. The entire garage door was lit about twice as bright at the Cat-Eye 400. The beam pattern was wider at about 30 feet.

The Cat-Eye 510 was third overall. This was the most expensive light and was about 25% brighter than the Cat-Eye 300. The beam pattern was the same as the Cat-Eye 300.

The next best was a surprise. The ACE Hardware six inch flash light was actually quite good. The beam pattern was more broad without the jack-o-latern streaks of the Cat-Eye lights. It would make a good bike light if there was a way to secure it to the handlebars.

Even more of a surprise was that the old fashioned Cat-Eye Halogen 500 tested so well. The beam pattern was bright at 100 feet and the somewhat yellow illumination was actually easier for me to read my little sign on the door.

I asked Susan to give her ranking of the lights from dimmest to brightest. I shined the lights in random order for Susan to evaluate. Her rankings were the same as mine with the Halogen light testing out as the most visible for illuminating 100 feet in the distance.

That got me thinking that a rating of usable light might be better system than candlepower ratings. I lined up all the lights side by side spaced two feet apart. True to the candlepower ratings the Cat-Eye LED 500 was the brightest. All the LED lights were almost blinding to look straight into at from 50 feet away. The old Halogen looked like it should be used for a romantic dinner in the back corner of a restaurant.

So why was the dimmest light the best for seeing? I had a similar situation during a 400 KM Brevet in 2003. I had two bright Cat-Eye 300 LED lights shining down the road but I had a hard time seeing the difference between the grass along the shoulder and the pavement. For the 600 KM I switched to two Halogen lights. On the same stretch of road I only needed one light to see fine. I used the same lights at Paris Brest Paris and they worked well. The only problem is that the 4-AA battery life is not that great and needed to be changed every three hours.

There might be a better scientific explanation as to the best lights for illuminating to road. I just know for me the Halogen wave length makes it easier for me to see the road than a more powerful LED light. Maybe you have had similar findings or prefer the LED light better. These are just some things to consider when choosing a light for night riding.