LED Lights vs Incandescent Lights

I'm sure this topic has come up before, but I couldn't any thread discussing it in detail in the archives. If this has been dealt with before I'd appreciate a link to the relevant thread.

I've seen quite a few posts here and elsewhere claiming that in some situations incandescent lights are "better" than LED lights, especially when there's some ambient light about. I don't fully understand why this is so, but it definitely agrees with my own observations. Incandescent lights almost always seem to show more detail than LED lights of comparable brightness, especially when there's a lot of scattered light about. LED lights really only seem to hold there own when it's really dark.

Why is this so? Is there any real explanation behind this phenomenon? Or is this just a subjective thing, like so many things?

Hans

Nice post Hans, another newbie here also wants to know?

Will there actually be LED innovations in the future where they would be at par with incands in this regard?

I think it's a matter of the color of the ambient light versus the color of the flashlight beam. If for instance the ambient light is from a cloudy afternoon sky, the scattered light will have a rather high color temperature (6000 K), and in this case an incandescent light with it's yellowish (3000 K) light will stand out more than an LED with it's 6000 K color temp. On the other hand, at sunset with a yellow/orange sun (2000 K) in the horizon, an LED will stand out more with it's considerably higher color temp.

Sunlight at high noon on a clear day has a color temperature in the 5200-6000 K region, and in this case the beam it self from an LED will be more or less invisible. This doesn't mean that the LED light doesn't illuminate things, but rather that you can't tell weather an object it's lit by the ambient light or by your flashlight. Also it doesn't mean that an object is better illuminated with an incandescent light. It just means that it's easier to distinguish the two sources of light due to the big difference in color temp.

Just my 2 cents.

Jan

If you want more information you can check out these links:

This thread on the topic of Incan vs. Led is being discussed in Incandescant.

This thread too.

Grox said:

If you want more information you can check out these links:

This thread on the topic of Incan vs. Led is being discussed in Incandescant.

This thread too.

Click to expand...

Thanks a lot. I reckon I should really start reading the Incandescent Forum again ...

Hans

Seems to me that whenever visual accuity is to be enhanced by optical means, i.e. driving glasses, shooting glasses, etc., amber is the filter of choice. This filters out the UV and blue end of the spectrum. Edges and contrast appear sharper. It's easier to see and identify objects, and then react appropriately.

That may be why some don't care for the bluish, purpleish tint of many so-called 'white' LEDs. The upper spectrum seems to cause visual interference.

As the state of LED lighting art is refined, we will see less and less of this blue stuff. For now, I'm through with blue.

My understanding is converging on the idea that incans provide better seeing, but LEDs provide better performance otherwise.

Scott

I replaced my Pelican M6 incan with a Pelican 3 watt haIII. I based my decision on function only. I compared them in my lightless backyard and found them fairly even in light output. Different colored light, but the same in my opinion. I opted for the led as battery life should be longer.

beezaur said:

My understanding is converging on the idea that incans provide better seeing, but LEDs provide better performance otherwise.

Scott

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Since flashlights are for 'seeing', if you can see better, it equates to better performance.

I like LED flashlights. I don't have any incandescent except an
old MagLite 3D.

However, it will be a while before LED catches up with
incandescent for high visibility applications.

Physics dictates that if LED needs a heat-sink, energy is
being wasted. I have not seen any need for beefy heatsinks
on incandescent torches.

High intensity LEDs (e.g. Luxeon) are like internal
combustion engines. Lots of waste for little output
power.

I understand that my view is not shared by most of you
here. But I have not seen a good logical rebuttal.

- Vikas

Vikas Sontakke said "...High intensity LEDs (e.g. Luxeon) are like internal
combustion engines. Lots of waste for little output power."

Actually incandescent lights are more like that. They're often described as a heat engine that produces a little light as a by product.

LED lighting is generally more efficient, but there's great variability. Some older white LEDs are hardly more efficient than incandescent.

By contrast the upcoming new Lumileds K2 will produce 60 lumens per watt, which is vastly more efficient than any incandescent:

http://www.lumileds.com/lightfair2005/Luxeon_K2_Lightfair.pdf

You're right that ALL LEDs as a group are not necessarily very efficient:

http://www.otherpower.com/otherpower_lighting.html

Although incandescent are inefficient and produce lots of waste heat, they can radiate away much of this heat in the beam. Put your hand in the beam of a powerful incandescent light and you can feel it.

By contrast LEDs cannot do this as effectively and heat must be removed by conduction. That's why high powered LED flashlights get hot -- NOT because the LEDs are less efficient, but because they can't radiate the waste heat in the beam like an incandescent.

Vikas Sontakke,

A tungsten coil in a vacuum can handle high heat. In fact so hot that it glows making light. Let oxygen in and poof there goes the filament.

LEDs are doped silicon that is not in a vacuum. Silicon cannot handle anywhere the heat that tungsten can, and thus requires a heat sink to dissipate the relatively low amount of heat generated. An LED does not produce light by heating up to the point that it glows.

alard said:

Since flashlights are for 'seeing', if you can see better, it equates to better performance.

Click to expand...

Yes and no.

You can see better with an incan for a time, while the batteries are able to sustain bright levels. It has a spectrum which quite objectively is better for seeing colors and using in fog and haze than the typical white LEDs of late.

But other things equate to performance as well. LEDs are enourmously more flexible and durable than incandescent bulbs. They dim, they strobe, they come in colors, they are more efficient. In giving up those things for an incandecsent's spectrum, you pay a heavy price for that (ever dimming) better light quiality.

Scott

If you ever have to find your way out of a smoke filled building or home, you will thank God you had a incandescent light. Also if you have to find your way in a foggy night. In these conditions with a LED light it will look like you are lighting up a wall of bright fog or smoke right in front of you, a good quality incandescent light will cut through these conditions that will leave the LED lacking.

LED lights are great around the home and to carry for a general purpose light. But if you want a light to carry or leave beside your bed for emergencies or if you are using it for defense in areas with ambient light the incandescent will be far better.

If you are worried about durability get a light like the surefire M2, M3, M3 Turbo, M4 or M6. These light have shock-isolated bezel/lamp assemblies and are very durable. My first choice of all of these lights is the M3 if you are going to be using it both inside and outdoors. If you are just going to use one outside the M6 is great and a turbo head for the M3 works well outside too. If you want something smaller the M2 is a great little light.

If we are talking about durability, LEDs are more durable than incandescent lights but with the surefire M-Series you have all the benefits of incandescent lights with the durable shock isolated bezel/lamp assemblies, I have dropped my M3s, M2 and M6 several times and never had a problem with them and I use my M3s every night.

With all flashlights we must remember that they are a mechanical devise and that they all can fail when we need them most, which is why we should all carry a backup light or at least an extra lamp assembly and extra batteries.

If anyone thinks I am bashing LED lights they are wrong, I love LED lights but I will not recommend them to people who are using them in emergencies or for defense. I know they make great LED lights for defense and I like some of them, especially my Night Ops Gladius but it will not be replacing my M3s anytime soon.

I think the suitability and capability of an LED light vs incandescent for a given task depends on the specific light.

E.g. an Elektrolumens 6D Tesla-6 puts out 432 lumens for SEVERAL HOURS, which is pretty impressive. No other conventional hand held incandescent flashlight I'm aware of even approaches this combination of output and run time.

If I wanted a bedside self defense light I could either blind someone or hit someone with, I can't think of a more capable light than a Tesla-6, whether incandescent or LED.

Even the incandescent Tigerlight puts out less output, run time is a fraction of the Tesla-6, yet costs about the same. I guess if you got the pepper spray model it would have a self defense advantage.

http://elektrolumens.com/Tesla-6/Tesla-6.html

joema said:

E.g. an Elektrolumens 6D Tesla-6 puts out 432 lumens for SEVERAL HOURS, which is pretty impressive. No other conventional hand held incandescent flashlight I'm aware of even approaches this combination of output and run time.

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It is real easy to build a 6D incadent light that both gives you more output and longer runtime.
But who want to carry around a 6D anyway? Must be crazy people IMO.

Sigbjoern

Lurveleven said:

It is real easy to build a 6D incadent light that both gives you more output and longer runtime, and that without frying some poor LEDs. But who want to carry around a 6D anyway? Must be crazy people IMO.
Sigbjoern

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If it's easy to make a 6D incandescent that gives BOTH more output AND longer runtime than a 6D Tesla-6, they why does nobody offer one?

Luxeon III emitters produce about 23 lumens/watt at 700mA. A xenon bulb would have to beat that or else it's impossible to have BOTH better output AND runtime. It doesn't appear possible (for non-HID), as similar lights have a lower output/runtime combination. E.g. the Streamlight Ultrastinger produces 295 lumens but only for 1 hr.

Also the Elektrolumens Tesla-6 isn't just 6D -- it's available in 6C and 3D.

Don't know what you mean about frying LEDs. Has any Elektrolumens owner reported that?

Re only crazy people would carry a 6D flashlight, Mag has sold many thousand 6D Maglites to police departments, plus others who want those features. They're not crazy -- there's a viable use for those.

430 lm / 6 LEDs = 71.something lm/LED from a LED with a nominal 80 lm rating, which does not include "flashlight" losses. Sounds approximately "spec" to me.

Scott

PS: The site says, "Six 3 watt Luxeon LEDs, powered at 3,000mA." I assume that is 500 mA per LED?

Both have their place. Neither is "Better"

Incan = "Brighter, More throw"

LED = "Stronger(will not break when dropped or bulb die), WAY better run time"

Think LED think flood light, Indestructable.

Think Incan Think "High Beam"

Then there is HID, a whole other animal......

I have removed my statement about the frying. I overlooked that the 6D version was wired differently than the 3D version so I thought 1.5A was going through the LEDs, but I now see that it will be 1A instead. Sorry about that. However, I assume the light is only resistored (?) so it would be interesting to know if the lumen rating applies to the start of the run or if it is a value halfway through the run. I really think all LED lights should be current controled.

If you use a CA1057 bulb in that 6D, then you will get 452 lumens and ca. 4.5 hours runtime (the bulb use 2.2A and produce 28.5 lumens/watt, you can even achieve 33 lumens/watt with some bulbs). 452 lumens is rated half way through the run, it will be brighter at the start of the run. You can also use brighter bulbs than this and still have several hours of runtime.
But just comparing the lumens doesn't give much meaning since the beam layout is so different.
Btw, you can use the CA1057 in a Mag 2D and get the same runtime as the Tesla6 in a 3D.

I really doubt the Mag 6D is a very popular light, thousands are not very much compared to the millions of 3Ds. I might be stupid, but I don't see any good reason for anyone to own a 6D. I really feel sorry for those poor LEOs that needs to use a Mag 6D.

Sigbjoern