Wednesday, March 21, 2012

Commuter light review - Sigma Lightster v. Planet Bike Blaze 2 Watt

Part One - 
First impressions and light patterns 

The Sigma Lightster is a potentially significant new option in battery powered commuter bike lights. Generally, commuter lights are used "to be seen" or "to see". A "to be seen" light is the kind of light you can use in a city where streetlights and other ambient lights provide enough light to ride by. It keeps you from becoming a "bike ninja" by making you more visible.  Since the "to be seen" light is mostly used to get you noticed by others, it can be a one bulb blinky or a small light.

If you ride unlit roads, a blinky won't cut it. You need a light that you can actually use to see where you are going.

The  Lightster is advertised as a "to see" light. It retails for about $35.00. What makes it potentially significant is that it is a shaped light. A shaped light is a light that projects a square or rectangle of light instead of a circle. A shaped light has a distinct top line. Like car headlights on low beam, the light is focused on the ground and not into the eyes of oncoming traffic. For the rider, it means that more of the light is used on the road ahead instead of fading off into the distance. This feature means that this light is one of the few battery powered lights that meets German standards for bike lights. Even more importantly, the Lightster is the ONLY shaped light I am aware of that sells for less than $40.00. Other shaped lights cost far more. 

The Lightster is also advertised as putting out 20 lux of light for 10 hours. A lux is a measure of light. I understand one lux to be about as bright as the light from a full moon. (if that's not right, feel free to comment)  By comparison, the Ixon, which is a very good  battery powered shaped light, puts out 40 lux for 5 hours or 10 lux for about 20 hours. So the Lightster, contrasted with the Ixon, either provides half the lux for twice the length of time as the Ixon high beam, or twice the lux for half the length of time as the Ixon low beam.  But the Ixon also costs well over $100  - enough to buy almost 3 Lightsters!

 I decided to test the Lightster against the Planet Bike Blaze 2 Watt in an under $100 light comparison. The Blaze is a Cree LED commuter light that retails for about $60 dollars. I have used it on overnight rides and it is an acceptable "to see" light for unlit paved roads with no major downhills. For commuting, it is way more than adequate. If the Lightster can hold its own against the Blaze, it's a light worth consideration.

 First Look 

The Lightster has flat black metallic body with what appear to be aluminum ends. I suspect they act as heat sinks which help keep the LED cooler. It takes 4 AA batteries and comes with Duracell Ultra. You can also buy a rechargeable battery kit and connect the charger directly to the light.

The Lightster has one level of light - ON.

The Blaze has black metallic body with what appear to be an aluminum heat sink mid-body.The Blaze takes 2 AA batteries.

The Blaze has 3 light levels Low, High and "SuperFlash" (Superflash is a mixed intensity strobe that is used "to be seen" It works great for that, but I am not testing that feature in this post)

Smaller circumference on the Blaze:
Blaze on left,  Lightster on right

 Comparable length:

Light Patterns
The following pictures were taken on the same night with the same camera seconds after each other. The images are unretouched. The lights were mounted side by side at the same height at handlebar level. The camera was on a tripod at about eye level for a rider. 

A tennis court was used then a dark trail. 

First, the tennis court test. 

A standard size tennis court was used so that the distances could be appreciated by anyone with access to a tennis court.

In the first series of shots the front hub was directly over the base line and the lights were aligned so that the top edge of the light just touched the top of the net

Sigma Lightster(click to enlarge)
The Lightster has a much wider coverage area than the Blaze. You can see the left sideline fairly clearly. The light also extended across the full length of the court. However, there was a unlit gap between the front wheel and the lit area. On a paved surface, that gap would not be an issue. It might be a concern on a bad surface. This would make a fine light for flat, paved unlit roads and bike paths, especially if you are riding a bike with wider  tires that can roll over small imperfections.  

Blaze on low
The Blaze low beam is narrower and dimmer. As a supplement to ambient light it could be enough, but it would not do well as a primary light for riding anything more than a very casual pace on a paved road. 
Blaze on high
The Blaze high beam is noticeably brighter than the Lightster, but the light is concentrated in a narrower pattern. In this picture you can seen how the light forms an oval on the surface of the court. There is no dark gap between the bike and the light, but the width is narrower. The reach of the light (or throw) is somewhat misleading because the light is positioned slightly down so that the top edge is at the net line. Tilting it up would decrease the light on the ground but increase the distance it reached - kind of like with a flashlight.

In the second series of pictures, the bike was on the sideline and the light was aligned so that the top edge just grazed the top of the wall on the opposite side of the court.
Lightster cross court
The dark gap of the lightster is evident here at the bottom edge of the frame. In reality the contrast is less, so the dark is less dramatic, but it is noticeable. You can also see the boxy shape of the beam and it equally lights up both sides of the mid court line.

Blaze on low
The Blaze on low is still long and narrow.

Blaze on high
The Blaze on high is bright. The circular pattern is evident. The trick with this pattern is trying to balance forward light with ground light. Still, this light works for night riding.

Finally, pictures of an unlit trail. Here the top of the light was focused on the fence in the distance. 
Lightster on trail
The lightster has a wide beam and good light over the area. It has the farthest reach as set up. (The camera exaggerates the darkness at the bottom, but there is a gap.)

Blaze on low
The Blaze on low shows more of the path, but less distance.

Blaze on high
The Blaze on high shows path and distance but less width.

Both lights on
Both lights on is impressive.  You get the best of both. If I use these lights for a real night ride, I will probably bring both and keep this option as a "high beam" for bad roads, downhills or rain. 

Test Ride

I tested both lights on a ride to, along and from a bike trail at speeds ranging between 14 - 18 mph. The trail had little ambient light. Under these conditions, the Lightster's wide coverage and shaped beam made for a noticeably better riding light than the Planet bike. Simply put, there was more light where light was needed. I also found that the coverage of the entire trail to provide greater options for line selection.

The Planet bike's strobe option was my choice for traffic roads under streetlights. That strobe demands attention, which is what you want on a city street. 

Next up - Burn time and "rain"  testing!

Feel free to post questions, requests or comments about the testing!  
Kent Peterson has a review of the Lightster's little brother the Sigma Roadster on his blog. (click for link)


  1. I can never discern my preferences in lighting from the beam snapshots. Even at Peter White's site, I'm never sure which beam I prefer.

    However, i can tell that your test setup has bars for a bmx/townie bike. This leads me to wonder if perhaps your fleche team will be riding such steeds? :) Also, a bit more seriously, what kind of handlebar mount is supporting the stub bar for the lights?

    1. It's very interesting what type of information people find helpful. I found Peter White's pictures quite useful in seeing the differences in the headlight beams which is why I used pictures for this post. I guess visual information works for me. Do you have any suggestions for other ways to show the differences? I was going to add my observations/comments as well.

      As for those handlebars, they are on my Brompton. I am not hip enough to use a BMX or townie as a commuter. I am also not fast or adventurous enough to use the Bromtpon on the Fleche. So the Fleche will be done on a much more traditional steed.

      The lights are attached to a Topeak Bar Extender. It's a nice little add on to increase the gadget room. It make a great place to attach lights below handlebar level as well which is how I use it on the fixed gear bike.

  2. Nice start of a review, excellent and useful article. Wish I had written it but have been off bike since June because surgery but am hoping to be back riding again in July.

    I am adding you to my list of followed sites on my blog that has been neglected for last year but will be revitalized as I get ready to ride again.

    Thanks for sharing. ... Roland

  3. Thanks for reading and commenting. Good luck on the return to riding.

  4. Nice info. When will we find out the results of the rain testing and battery life tests?

    I just got a Sigma Roadster which looks to have a similar beam pattern but it's a 2 AA powered light, just a bit smaller than the Planet Bike Blaze.

    I have a heck of a time getting good beam shots, however!

    1. Kent,
      Wow. I guess I am long overdue for the promised part 2! I've been semi-working on a plan to do a reasonable burn comparison with some photos. The challenge is that LED lights get dimmer as they burn up batteries, so how do I tell/show when the significant dimming starts??? I have a few ideas and something will be completed soon!

      As for the beam shots, I used a tripod and the camera's self timer to avoid all shaking. That's it nothing fancy.Thanks for reading and the link.

  5. Thank you for this test, now it seems that I made the right decision when I ordered the Lightster a couple days ago.

  6. One lux realy is not a light intensity of full moon night, full moon night can have luminous emitance between 0.1 - 1.0 lux.

    1 lux is 1 lumen per square meter, or 100 cd luminous intensiti at a defined point. If you have 20 lux guaranted luminous emitance on StVZO (germany approved) light, this mean you have 2,000 cd @ 10 m from the light, in strictly defined points.