Why Are “Colder” LEDs Brighter and Cheaper?

Why do I get more flux than at “warm white” – partly even for less money at many LED lamps with “colder” temperature ? This question I hear again and again and will be answered here for everyone.

Left a “Neutral white” verbatim LED spot, on the right a “warm” Spotlight “LEDs change the world”. Here, not only the colour but also the subjective brightness differs.

Blogleser Fabian from Waghäusel is in the middle of a major conversion: A rail system, at which five E14-“Energy saving” (i.e. compact fluorescent lamps) were installed, should be equipped with enough bright LED Retrofits. On the versions is “9 Watt / 230 Volt”. His question to:

“I myself looked around on the Internet and found that light source with a colour temperature to 3000 to 3400 k have lot more lumens than bulbs with 2600 K (with same wattage). Also, the bulbs are cheaper to 3000-3400 K almost by half. Can you tell me why this is so?”

My short answer:

“differences at least in the major brand manufacturers are not so extreme.Take a look at, for example, time the data these lamps with different colour temperatures to; they differ little in price and luminous flux.

In principle, the difference in the human perception of brightness is – lumen is a unit of it-oriented. “Cold” light (with a higher Kelvin value) appear lighter than “warm” with equal energy, has more lumens. Details there. In this test I have also examples by other manufacturers.

That some LED lamps are significantly cheaper (and even more efficient), is but mostly on the poor light quality (color reproduction) and lifetime, not on the color temperature. “Quality costs just unfortunately efficiency and lumen and more at the box office.”

Search so far no satisfactory result

In his second mail was Fabian fleshed his previous search:

“I bought myself for the five versions of LED spotlights by Segula 2,3 W and 2800 K. They are but too dark to me, not well lit the room and spread a quite unpleasant light. That’s why I want to buy me with a color temperature around the 2600/2700 K 360-degree lamps. You should provide 200 lumens or more.

To do this I looked to me already in the Internet and me from the hardware store bought onealso, to even have a comparison value. Why these costs when compared to the others, I’ll just list, twice as much? She has a poorer colour rendering index (RA 75), less lumens and a worse efficiency in comparison to the other.

This would very well, but unfortunately no 2600-2700 K liked. also a LED lamp, that would suit me, but still too much Kelvin has. When This Sebson lamp design for me would be perfect; But why has it only an viewing angleof 160 degrees? For me it looks like they would have to radiate more likely around 360 degrees.”

I will pass the last question right on the Sebson Chief Sebastian Sunday. Because he is one of my advertisers, I consider myself ‘ out (Update: now he has below responded in the comments). No surpriseis that the Segula lights not bright enough for me: 2,3 Watt power LED are too few to replace 9-Watt Kompaktleuchstofflampen. Nothing adequate with decent quality of light should be there currently under 6 to 7 watts.

Some prices have nothing to do with Kelvin

I think with around 16 euros, the 4.3 watt Segula purchased at the hardware store is simply overpriced. Bring the best right back, especially since 75 since September 2013in the EU no longer be sold lamps with RA for the Interior light may (at least RA 80) and it coming Thursday (20.2) at Aldi Süd is brighter E14 bulbs by “Müller-Licht” even in a double pack for 5,99 EUR (so less than €3 per piece – the hammer!). The default “200 lumens or more” is already too modest–there would I just grab at least again 100 lumens per lamp.

Planned is a dimmer in the circuit or for the future? This info is also very important when choosing. The major brand manufacturers have now – as well as some smaller providers or a Swedish furniture store – E14 round Spotlight relatively bright and color-accurate as “Candles” and “Drop” with up to 470 lumen (pictured right 6-Watt OSRAM-“LED Star classic B40″“); partly also dimmable. Thus, it is at least as bright as with 9-Watt-“E economy”-lamps.

A decent E14 LED lamp with 360-degree half angle there but to my knowledge yet – here must at least this year and the me this news information come out probably still with maximum around 260 degrees. But, that should be enough for most purposes. Maybe my blog readers can make Yes below a few other suggestions in the comments – best with concrete experiences.

Update: A blog reader points out in the comments rightly points out, that “warm white” LED chips due to the “tighter” luminescence conversion coating provide also objectively less brightness than “neutral -” and “cold white”. I had only briefly touched on the above with the phrase “Quality costs just unfortunately efficiency and lumen”.