Lower Kelvin values in the range of K to K correspond to a warmer light comparable to a conventional incandescent that enhances yellow and red tones.
Lamps with higher values typically K, K, K, and K give off a cooler white light that enhances blues and greens. These bulbs are often referred to as natural, bright white, or daylight lamps. The following table explains some terms you may encounter on lamp packaging. Try a few out with your family and see which you prefer. If the store where you are searching does not have a wide enough selection, suggest that they provide more offerings and try somewhere else. Tunable LED fixtures allow the user to adjust color temperature across a wide range so you can adjust the color temperature for different moods or times of day much like using a dimmer switch to control light output.
Desk and floor lamps as well as overhead fixtures with this capability are becoming more widely available. Lamp Lifetime. Expected lifetime can be an important consideration when selecting bulbs for hard-to-reach fixtures as well as those that are used infrequently.
These long-lived lamps will really pay off in the most used fixtures as well as those in high ceilings or other inconvenient locations. Halogen incandescents typically operate for 1, hours; extended-life versions can last for 3, hours. Select longer-lived LEDs for your most-used fixtures.
Less expensive LEDs with shorter lifetimes around 10, hours are a good choice for closets or other spaces where lights are rarely on for more than a few minutes. Short operating cycles can negatively affect CFL lifetime so they are not as good of a choice for these spaces. If within 10 years from the date of purchase you are not completely satisfied with the performance of this product, return the product to Cree, Inc. Cree will send you a replacement or at Cree's option refund the original purchase price.
Cree may require a purchase receipt. For warranty and other questions, please call Some states do not allow the exclusion or limitation of incidental or consequential damages, so the above limitation or exclusion may not apply to you.
This warranty gives you specific legal rights and you may also have other rights which vary from state to state. To help consumers understand light bulb efficiency, the Energy Independence and Security Act legislation directed the Federal Trade Commission FTC to change its current labeling requirements for all medium based general service LED bulbs. The Lighting Facts label helps consumers base their purchase decision on the brightness lumens of the bulb and cost of operation, instead of wattage.
The label is an industry tool to help buyers evaluate product performance against manufacturer claims. Hover over Tap the to learn more.
Connected Max. Reflector and Downlight View All. Candelabra View All. Want more options? Where to Buy. Today the same quantity of light can be produced by an incandescent bulb using 60 watts, a halogen bulb using 42 watts or a compact fluorescent lamp using 15 watts. This causes confusion and so with the intention of fixing this problem 'lumens' are now included showing the 'true' measurement of the lamps brightness. In effect a universal measurement of any lamps brightness, the higher the 'lumens' the more light emitted.
Like most electronics, LED performance will suffer a bit as the bulb heats up specifically, the brightness will dip slightly. That's why LEDs incorporate heat sinks, convection vents and other thermal management tricks that help keep the heat at bay.
The good ones are able to hold that brightness dip below 10 percent before stabilizing things. The results here were impressive.
The graph above charts each bulb's brightness as a percentage over time as in: they all start at " percent" of whatever the very first reading is and then go down from there. Each and every bulb stayed well below that 10 percent benchmark, and seven of them even held the heat-induced losses below 5 percent. That's a great sign that LED tech is continuing to improve.
Bulbs with better color-rendering abilities will produce whiter whites, more natural-looking wood and skin tones and colors that look vivid and more accurate, particularly reds.
More and more, manufacturers are using claims of superior color quality as a way to set their bulbs apart -- but in most cases, the difference made is pretty limited. Along with examining the spectral data of each bulb, we also put each one through the good ol' eye test to determine which ones make a difference that you can actually see.
Few live up to the promise of truly eye-popping reds and vibrant whites. As I said before, the most consistent exception is the GE Reveal line. But again, those bulbs do it by taking the somewhat drastic measure of filtering out a good chunk of the yellow part of the spectrum, leading to bulbs that aren't as bright as they probably should be.
I plan on updating this post throughout the year as I'm able to get new bulbs into the lighting lab, so stay tuned. For now, here's a running list of every bulb considered for this rundown thus far:.
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