LED lighting

[Did67]

it's a real headache!

I'm starting to find my way in lm, in K ... And there, you see very quickly much clearer! [I'm doing it on purpose!]

90 lm per Watt is a bit of my benchmark.

Yours would make 100

I find that temperatures of 3 K pass well. I acquired some cold LEDs, and here it is freezing! Weird: the technical sheet of yours indicates two temperatures. I did not understand.

[Obamot]

Glad that the debate on LEDs is taking shape ...

Some pitfalls to avoid however ...

- At the same consumption in watt, we get a different number of lumens depending on the LED performance. So it is better to avoid bulb LEDs, which have a much lower yield than SMD LEDs, or chip-LEDs (except Cree) and among SMD LEDs too, there is food and drink, you get 20 watt will produce 2400 lumens, while others at 30 watt will produce only 1800 lm ... (the more lm, the more light it gives ...)

- The best LEDs (consumption watt / h VS production of lumens) are not Chinese but Amérloquoise (the "Cree").

90 lm per Watt is a bit of my benchmark [...] I acquired some cold LEDs, and here it is freezing!

- To have "freezing" cold light, it would have to be between 7 ° K and 000 ° K, we find it extremely rarely (except on the web);

- Lumens have absolutely nothing to do with color temperature (° K). However a neutral light without dominant, will tend to "illuminate better" for our eye than a yellow-orange light where we will have more effort to make to distinguish things (although apparently, the tones will be less shimmering, apparently only. because in fact - since these are neutral tones - it will be the objects around us that will not ...);

- we should not confuse the color temperature in ° K seen by our eyes (the photographic) and that of the light source ...

LIGHT SOURCE:
- The higher the ° K (> 6'500 ° K) the more blue the light will be;
- Those who claim on the packaging that 5'000 ° K is "daylight" are mistaken (it is a low limit not to be below this, already in warm color temperatures, even if that remains white, below it becomes frankly more and more yellow-orange, and therefore less and less neutral for our eyes ...)

PHOTOGRAPHIC:
- The lower the settings for ° K, the more blue the photographic rendering (so it's the reverse);

Hence the frequent confusion ...

- With any light source, the lower the ° K will be (<6'000 ° K) the more the light will be yellow-orange (up to the awful colors of tungsten lamps, but some like it, even if not at all our eyes...);

WHILE FOR OUR EYES THE IDEAL BDB IS 5 ° K for the vast majority of people (see the Kodak and Konika studies, in the 250s, tested on thousands of people.)

Proof of this is the success of xenon lamps (VS halogen) our eyes prefer "daylight" for the lighting produced by car headlights ...

In summary:
- good performance for 10 watt LEDs, it will be ≥1'400 lm ("ok" from 1'200 lm);
- below these yields, there is nothing exceptional (<900 lm, the price must be seen ... So LED bulbs, yield at 90 lm / Watt we are already in old technologies, even the hard-discounters sometimes do better);
- a good neutral color temperature for LEDs, it will be between 6'000 ° K and 6'500 ° K (below you tire your eyes, above it becomes "cold" as color rendering);

Also be careful at one point, I gave up importing them for insurance reasons. In the event of a fire, if it is "regulatory" equipment, insurance companies will not have this pretext to reduce their benefits ...

[Did67]

However a neutral light without dominant, will tend to "illuminate better" for our eye than a yellow-orange light where we will have more effort to make to distinguish things (although apparently, the tones will be less shimmering, apparently only. because in fact - since these are neutral tones - it will be the objects around us that will not ...);

For my part, I find that it depends on the use: even if the LED, its specialty is not the lighting of atmosphere, there, I take relatively low K; therefore a relative "yellow" light; I find it relaxing ...

On the other hand, to read, I prefer an LED which spits and which is "colder" (therefore higher K, indeed). Yesterday evening, with hardly more power, I just replaced an LED in a reading light placed within reach of the sofa. And that changes everything, for barely 1 W more, I believe ... It is a 4 K (which they call "neutral white").

But I come back to my point: for a Boeotian, it's quite a learning process, these powers (in W), this lighting power (in lm: lumen) and the color temperature (in K). And again, I pass on the CRI.

[Obamot]

However a neutral light without dominant, will tend to "illuminate better" for our eye than a yellow-orange light where we will have more effort to make to distinguish things (although apparently, the tones will be less shimmering, apparently only. because in fact - since these are neutral tones - it will be the objects around us that will not ...);

For my part, I find that it depends on the use: even if the LED, its specialty is not the lighting of atmosphere, there, I take relatively low K; therefore a relative "yellow" light; I find it relaxing ...

No that's what I said above, it's the color of the decoration that it would be worth changing for our eyes and NOT the color temperature of the lighting! Which combines the two, neutral lighting "nice for our view"," fair "colors, neutral reading light at all times ET shimmering tones if you want, but not at the expense of the eyes ...

This is how it would be better to choose the colors of its walls, its furniture, floors and curtains under lighting: "daylight" !!! This is where we should have learned to choose the shimmering tones we want (and not a posteriori and in my humble opinion ...)

On the other hand, to read, I prefer an LED which spits and which is "colder" (therefore higher K, indeed). Yesterday evening, with hardly more power, I just replaced an LED in a reading light placed within reach of the sofa. And that changes everything, for barely 1 W more, I believe ... It is a 4 K (which they call "neutral white").

But I come back to my point: for a Boeotian, it's quite a learning process, these powers (in W), this lighting power (in lm: lumen) and the color temperature (in K). And again, I pass on the CRI.

"Neutral white", it would be at least 5 ° K, but sometimes the resellers / distributors themselves confuse these notions. But 000'4 K CANNOT be "neutral" (... although the important thing in all of this is that it suits you, of course ...)

In the Kodak study, then that of Konika (and also Fuji) the human guinea pigs did not know which ° Kelvin they were dealing with ... They had yet to express well what for them corresponded to "neutral" tones (I want say without dominant). at 4'000 ° K for sure, there is already some dominant (our eyes are already starting to be sensitive at a level of 250 ° K, then a 2 ° K difference compared to the standard, it is huge: it cuts a lot!)

[chatelot16]

we should not confuse the output of the component LED alone and the output of the entire LED lamp: the low voltage 220V converter for the LED is far from perfect

I just dismantled one that I found particularly heavy ... I will make an autopsy report with photo ... the decoupage converter is complicated and it is a shame to put the weight in the lamp ... and we cumulate the heating of the with the heating of the decoupage converter to reduce reliability ... and above all this converter coated in silicone resin is difficult to dismantle without breaking everything

so I prefer a converter separated from the lamp less miniaturized so more easily dismountable and repairable

less miniaturized also makes it more reliable

for a 10 W led there is not even need for electronic cutting: it could be a 50Hz transformer with magnetic leakage to make current regulator and a simple diode bridge ... it does not fit into a bulb imitation lamp but it fixes where you want in the house

there will be a sequel

[I Citro]

If the Lumen indicate the light output, the color temperature in ° Kelvin is insufficient to qualify an LED.
We have therefore developed a new indicator: the IRC (Color Rendering Index).

[Obamot]

Quite ... But it is to sell very expensive lambda LEDs and which even without that make the job perfectly that they are asked ... If you can differentiate from memory a derivation of 180 K I will offers a racing thermocolorimeter! Mebon, standards are very useful, especially for the production standards of an industrialist. Because when leaving the factory, the promised tolerances are always there (except in the extreme edge but it is not significant in use, even in photography ...)

I made tests of shots with 1st price lambda chip-LEDs to test suitable high-flight reflex and optical cameras (and obviously in latest generation SMD chip) without them being stamped in accordance with "photographic requirements" "and it works very very well when you are between 6'000 K and 6'500 K (the colors fart in your face, they are" correct "and the" neutral grays "are perfect ... The BDB is nickel whether it is in the HL (white from white) the BL (deep black) or the reference chart in 18% gray, ditto with a CMYN charter and contractual proofing, no problem encountered to date! LED bulbs from five years ago, it was sold for "daylight", but it gave a slightly yellowish-greenish pissy rendering (but it was the techno of the beginning ...)

we should not confuse the output of the component LED alone and the output of the entire LED lamp: the low voltage 220V converter for the LED is far from perfect

Yes indeed, we must not confuse ... Note that when the consumption of 10W, 20W, 30W etc. is announced with a "finite" number, it is indeed the consumption of the chip we are talking about.

There I have just looked at the last ones, on these it is marked 20W "approximately", can we then conclude that it is about the consumption of the whole ...? To be checked, but anyway, it's mini switching power supply circuits must consume peanut relative to the consumption of the chip ...

[Did67]

For a Boeotian like me, in fact, we compare light bulbs. So the "yield" that I indicated is that of the "ballast + LED" assembly ...

And indeed, the ballast heats up a bit ...

For the temperature, we can, in fact, sometimes adapt the decor. But when it comes to reading, the book is a book ... So we adapt the LED. And there, the cooler LED is more "efficient" than the hotter LED it replaced.

[chatelot16]

other led merchant that looks like the one I took at aliexpress
http://fr.myled.com/p5418-led-emitter-1 ... 0-33v.html

but the voltage is not the same: 30V while mine is at 10V in one there are 9 chips in series ... in the other there are the same chip 3 in series, and 3 group in PARALLEL

the choice of 30V is favorable to a better efficiency of the power supply ... the choice of 10V facilitates use in 12V

[Obamot]

For a Boeotian like me, in fact, we compare light bulbs. So the "yield" that I indicated is that of the "ballast + LED" assembly ...

And indeed, the ballast heats up a bit ...

For the temperature, we can, in fact, sometimes adapt the decor. But when it comes to reading, the book is a book ... So we adapt the LED. And there, the cooler LED is more "efficient" than the hotter LED it replaced.

What I mean is that if you look at the issue from a prevention perspective, you find that "hot" LEDs (or any other light) tire your eyes and aren't great for it. "mental". Therefore there is absolutely NO point in buying "hot" LED lamps, none.

Let me explain: we can very well direct a beam "White LEDs"on a surface (wall / s, cabinet / s, ceiling, curtains or whatever ...) in the direction of colors that one would consider as"hot", so that the whole room changes its atmosphere in"the look of the moment"! What we can do at will, on the other hand the reverse is not possible: with a hot LED lamp, no way to go back to colors"Neutral experts"subsequently ... (except to put a bluish filter - if indeed it is found" the one who is going well "- but it is still expenses, and that will lose a maximum in output ...)

Besides this idea of ​​LED "hot"is a bit of a figment of my mind, I've never heard of sunlight being light"Cold", quite the contrary, there is no" warmer "than the colors" pleasant "to our eyes and which do not tire them (but each one does what he pleases) ...

In my case (and given that we can create the atmosphere we want without it being harmful to the eyes) it will never be more than daylight LEDs at 6 K. The other huge advantage they represent is the fight against depressive states. With this lighting, we have the impression that "it's summer" all year round inside the household, no need to buy light therapy panels:
http://fr.wikipedia.org/wiki/Luminoth%C3%A9rapie

And a big advantage over dedicated panels is that "daylight" LEDs reproduce the full spectrum, so no side effects to worry about. In addition (since our brain assimilates them to sunlight) they help put the internal biological clock back in phase (but afterwards, everyone does what they please) ...