Two lights vs one
 

Is having 2 medium intensity lights similar enough to having a really bright single beam? For example, two 250 lumen lights comparing to one 400-500 lumen light. I ask this question because of the cost of lights such as the Cygolite Miticross 400. It's $250 but for $120/250lumen light I can get a "combined" 500 lumens for $240. Or am I just being ignorant? I also think having 2 lights is better because one can be run at the full 250 lumens to see while the 2nd can be run at the normal lower setting as a "see me" light, thus ensuring you'll rarely, if ever, deplete both batteries on the same ride at the same time.

Pretty much, you're right. A lumen is a measure of total light output. So given one light with 400 lumens and two lights with 200, the the two will product the same total light output as the one. If all three have the same light distribution pattern, the two will work like the one...except that with two you can aim each differently if desired. And you have redundancy. If you think that's worth having the added complexity and dealing with two light setups, go for it.

thanks. that's all I wanted to know. and it can't be any more complex than having to have that external battery pack for cygolites and niteriders. either scenario you have two pieces of equipment. though you do have to charge two batteries in the one i'm going for.

I would also try and use different style lights if you want to ride at a decent speed.. Mixing a floody light for closeup illumination and more of long distance thrower light at the outer edge of the floody beam to give you the best of both worlds.. Niteriders original lights use to do this.

I currently do this using flashlights on the bars..

For the same price I'd definitely go for the option with two lights. The redundancy is a real plus and you can set one up as your 'be seen' light aimed for the distance with the other light aimed more for seeing road obstacles - or have one head/helmet mounted with the other on the bike.

And in the event of an accident the usual excuse of 'I didn't see him' would be less believable if you have two lights on at the time - even if a single light would put out just as bright a beam.

I agree with what's mention. I would like to emphasized in the distribution pattern as Looigi pointed out. Depending on the reflector design and type of LED, the higher lumen led can be design such that the reflector can achieve a farther throw with less spill. You can have 2 x 250 lumen side by side and not get as good of a throw as compare to a 1 x 500 lumen with a reflector design for throw.

All this will depend on what you are looking for. Before deciding, I would look at the beam pattern of the Mitycross and compare that with the two other lights to see if the beamshot is satisfactory to your need beside just the total lumen of the lights.

A non-scientific answer, but I use two lights at slightly different angles and believe I get more of a 3-D illumination of the terrain. On smooth flat I can turn one off to conserve, if necessary.

Certainly having two lights offers more versatility than just adding the lumen output together. However there is one fundamental drawback of using a series of underpowered light sources. All else being equal, multiple lower-power lights will never add up to the " identical throw power" of a single more powerful light source and reflector.

So a key part of any lighting system is the maximum distance of user-acceptable surface lighting. In this case, a light system that uses two emitters side by side in a single case should not claim to double all aspects of the lighting patterns associated with a single emitter......

+1 here
R

Put 1 on the handlebars and the other on your helmet if you go with 2 lights. And then keep adding more like the rest of us.

+1

A Magic Shine is $100 for a 900 lumen light. LED flash lights with the same emitter (but less battery life) are even cheaper. Save your money and get more light.

Spending more doesn't even guarantee better life - I was going through a $150+ Nite Rider every few years before I gave up.

Most decent (so you can see) lights have a battery gauge of some sort and aren't going to run out unexpectedly.

You still want two because lights break.

The best solution will inevitably depend on what sort of cycling you're doing.

If you're riding unlit trails after dark you'll need a lot of light, thrown forwards and sideways. You may be better off with two lights so you can use one to light the path ahead a long way and another to throw light out sideways so you can see if, for example, there's an animal near the side of the trail that might move into your path.

If you're riding on roads that have street lights you're probably going to be more interested in being able to see potholes, while also making sure you are seen by other road users.

Depending on just where you want the light you might be better with one light or multiple lights. If you want high visibility then a dozen relatively dim lights will make sure you are seen. If you want to cast light a long way then you will most likely need a small number of powerful lights rather than a large number of weak lights (for comparison think of a single focussed beam from a krypton bulb and compare the results to the output from as many dim bulbs as you can imagine)

My night riding tends to be the latter situation - urban roads and lit MUPs so my lighting solution is a front flashing light and a flashing head torch. If I go through a section that isn't well lit I put the head torch onto its bright/steady mode, then put it back to flashing when I'm back under street light coverage. The beauty of a head torch is it illumates wherever I'm looking.

I think that pretty much trumps any other argument.

Part of any serious, any thoughtful discussion of bicycle lighting systems should be: How much money is left for my backup "emergency" light and or extra "all night" battery power. It does little good to have an exotic 1000 lumen light head if you are constantly running low on battery power.

Two of my strategies for all-night riding are using a low-power light on "strobe" mode until complete darkness so as to spare my main light's battery for really dark roads. Custom made "AA" battery packs serve as additional redundant power as well.


You see: When you're as big a weenie as Richard Cranium, you have to have TWO types of battery sources as well as TWO light heads to see where the sun don't shine.

I never thought about the "throw" power. I'm riding exclusively roads. I'm just wanting to avoid having that external battery unless it's a 2+hr ride. Commuting to school taking of an external battery is just an extra step I want to avoid. Having two smaller lights is still easier to take off than an external battery pack (because to avoid cable dangle I had to wrap it around the stem and strap the pack down). I do feel more drawn to the 400+ lumen lights.

^^^ This.

I now have enough lights to equip every one of my riding buddies. Between us we could light up a night-riding peloton.

I disagree with keep adding more lights. That's just more lights I have to take off when I get to school/work, reattach, and more weight to my bike. If I did get an external battery light I wish I could bolt the light itself to the bike and then simply just take the battery but I have one hole on the front of my frame just above the fork. Unfortunately every light I have seen that is bright enough for me is either clipped on or strapped on.

I like having two lights as well. I ride with a magic shine and a MTE SSC P7. Usually put the MS on the helmet for weight reasons and the P7 on the bars. It is nice to be able to direct the helmet light where the light is needed. Once you ride with a powerful helmet light, you will love it, and if you take your helmet with you, you just unplug the battery and leave it strapped to the helmet.

Having a 2nd light on the helmet makes a lot of sense. Beside the obvious of aiming it where you want to see while riding, it also makes one heck of a good repair lights when you have to replace a tube in the dark.

I can always tell the story about how a helmet light was the only way I spotted a skunk strolling into my path one night. I had a bright head light but this guy was crossing the road just as I was entering a turn -no matter the power - a mounted head light could not light up Odie Cologne.

Yep. One of my neighbors was asking me if my light was "one of those new bright 100 lumen lights the cops use" last fall. I had the magic shine and a LD2 on the bars, and a 2000 lumen light on my helmet then and he was surprised at how many lumens I had. It's hard to give them up once you've got them too.