7-Watt Collection LED 5000K Light Bulb (CL-L60A1-D , 40 Watt Equivalent) $6.50 + Free Shipping

Quote from brbubba : LEDs win on lumens per watt if you have the right unit. Then again, it's like anything, if you put cheap crap into the components of a product then you'll get crappy performance.

Would you care to share a link or two for light bulbs that have the kind of output/watt you are talking about?

Remember, we are talking about household light bulbs here... please don't quote some specialized LEDs that are used in some costly devices that do produce higher output than CFLs per watt. I am sure there are some LEDs like that (maybe the ones used in car headlights fit those characteristics)...

"Dimmable - No"

I'll pass.

Quote from rs01 : Would you care to share a link or two for light bulbs that have the kind of output/watt you are talking about? Remember, we are talking about household light bulbs here... please don't quote some specialized LEDs that are used in some costly devices that do produce higher output than CFLs per watt. I am sure there are some LEDs like that (maybe the ones used in car headlights fit those characteristics)...

Well I went to Home Depot's site and picked a whole bunch of CFLs and the best lumen/watt rating I could find was about 69.56 lumens/watt on these [homedepot.com]. This represents a best case scenario, many of these were below this, some by a few percentage points, some by 10% or more.

Second, I then picked LEDs and the best lumen/watt rating I could find was 94 lumens/watt on these [homedepot.com]. This also represents the best case scenario, however, the LED products they sold varied significantly more than the CFL products. If we plotted all of these products there would be significant overlap with many CFL products pulling ahead of many LED products.

Once I moved into a larger market segment, aka the Internet, I could not find a better efficiency for the CFL, but I was able to find an LED bulb with 100 lumens/watt here [amazon.com].

So yes, there are options for household lights using LEDs that trounce the CFL lumen/watt ratio. That being said, as a consumer, you need to do your homework. If I were to simply walk into a random homedepot and pluck a random CFL and a random LED off the shelf the outcome might not be so pretty.

Quote from brbubba : Well I went to Home Depot's site and picked a whole bunch of CFLs and the best lumen/watt rating I could find was about 69.56 lumens/watt on these [homedepot.com]. This represents a best case scenario, many of these were below this, some by a few percentage points, some by 10% or more. Second, I then picked LEDs and the best lumen/watt rating I could find was 94 lumens/watt on these [homedepot.com]. This also represents the best case scenario, however, the LED products they sold varied significantly more than the CFL products. If we plotted all of these products there would be significant overlap with many CFL products pulling ahead of many LED products. Once I moved into a larger market segment, aka the Internet, I could not find a better efficiency for the CFL, but I was able to find an LED bulb with 100 lumens/watt here [amazon.com]. So yes, there are options for household lights using LEDs that trounce the CFL lumen/watt ratio. That being said, as a consumer, you need to do your homework. If I were to simply walk into a random homedepot and pluck a random CFL and a random LED off the shelf the outcome might not be so pretty.

A lot of Slickdealers think a contrary opinion makes them appear smarter, but posts like yours (and the legwork contained within) are what make this place useful. Thanks. I wasn't even aware of the G7, very impressive.

That G7 brbubba mentioned looks nice, but damn, it's over $20 shipped.

Quote from rs01 : I don't know why people think that LEDs use less power than CFLs. For the same output, they use about the same amount of power (this thread was about a 40W regular bulb replacement and a 40W equivalent CFL also uses 7 - 9 watts).

LEDs *can* be more efficient but often are about the same these days. The real advantage is with instant-on, longer life, directional light (when that's an advantage) and no mercury.

Quote from roguephoenix : would this bulb be too bright for a lamp in a room? i've been looking for white light bulbs for a while now. don't like the yellowish tint on regular bulbs. makes me sleepy. currently using a 100 watt bulb and it's too dim.

No, this is nowhere near as much light as a 100W incandescent, but bear in mind that LED light is more concentrated (directional rather than omnidirectional like an incandescent).

Quote from croushore : A lot of Slickdealers think a contrary opinion makes them appear smarter, but posts like yours (and the legwork contained within) are what make this place useful. Thanks. I wasn't even aware of the G7, very impressive.

+1. Now if only more of those who were educated by the helpful posts would be grateful rather than argumentative in futile pursuit of saving face.

In for 1. Thanks OP!

Quote from brbubba : So yes, there are options for household lights using LEDs that trounce the CFL lumen/watt ratio. That being said, as a consumer, you need to do your homework. If I were to simply walk into a random homedepot and pluck a random CFL and a random LED off the shelf the outcome might not be so pretty.

This guy is on the right track. I'd expect commercial products to be offering 100lm/W on warm color temperature bulbs now days though. LED emitters themselves are quite efficient, especially emitters the last year or so at over 150lm/W at 1-3 Watts. The problem with these is that they are 5000-6000 kelvin. I think any commercial (time to market) products at 2700-4300K that do 100lm/W are a good starting place to purchase these things.

I wish someone would come out with a decent DIY fixture that can dump heat from a 10W emitter. Dealextreme's things are only good for like 3-5W emitters around the 100 or more lumens per watt efficacy. If LEDs were had higher efficiency in general (not efficacy - visible light), heat would be even less of an issue, and they could pack more light into a similar sized bulb. A $5 housing, $6 LED, and $1 driver would make an excellent 10W/800-1000 lumen bulb.

LOL. You guys are funny, and obviously have no idea what you're talking about. 3000k is considered "romantic" lighting? Hahahaha look out, we have an "expert."

All of you saying cool light is better for doing work and seeing details are absolutely incorrect. CRI (color rendering index) is the measure of a light source's ability to accurately reproduce colors. "Warmer" bulbs have higher CRI values than "cool" bulbs. As a result, light sources in the 2400k-3400k range are easier on your eyes, reproduce colors more accurately, and allow you to see finer details because of the increase in contrast.

I play with LED modules/drivers/boards almost everyday (huge flashaholic) and look at bin charts constantly. Look here: http://www.cree.com/~/media/Files...ampXPG.pdf

http://www.cree.com/~/media/Files...mpXPBL.pdf

Which colors have the highest CRI? 2600-3200k.

Yes, ~450 lumens for 7 watts is pretty weak. Most high-efficiency LEDs are now in the 100-150 lumen/watt range and it will increase from there quickly.

If you want more info on LEDs than you can handle, stop by here and do some reading: http://www.candlepowerforums.com/vb/content.php

Quote from brbubba : Well I went to Home Depot's site and picked a whole bunch of CFLs and the best lumen/watt rating I could find was about 69.56 lumens/watt on these [homedepot.com]. This represents a best case scenario, many of these were below this, some by a few percentage points, some by 10% or more. Second, I then picked LEDs and the best lumen/watt rating I could find was 94 lumens/watt on these [homedepot.com]. This also represents the best case scenario, however, the LED products they sold varied significantly more than the CFL products. If we plotted all of these products there would be significant overlap with many CFL products pulling ahead of many LED products. Once I moved into a larger market segment, aka the Internet, I could not find a better efficiency for the CFL, but I was able to find an LED bulb with 100 lumens/watt here [amazon.com]. So yes, there are options for household lights using LEDs that trounce the CFL lumen/watt ratio. That being said, as a consumer, you need to do your homework. If I were to simply walk into a random homedepot and pluck a random CFL and a random LED off the shelf the outcome might not be so pretty.

You do realize that the high efficiency bulb costs over 10 times the cost of CFLs, right? Multiply the numbers with the number of bulbs you need to change in a typical house, if you want to be 'certified' green. In my experience of using over 50 CFLs in my home with varying amounts of usage, CFLs also run pretty welll for over 5 years, except about 10% that die prematurely.

And as a consumer, I need to do all this homework to buy a light bulb? Compared to picking up a couple in samsclub/walgreens/homedepot while shopping for something else. If we do this sort of research for a common house hold bulb, just imagine the time we need to spend on researching when we buy a $1000 laptop... by the time we finish the research, there will be newer and better models and the cycle starts again.

I'm talking about being practical too... When I posted my previous comment, I was pretty sure that you are going to quote a $20 - $25/piece LED bulb and say... look here is a higher efficiency LED bulb

I think I spent enough time on this discussion already... so... if LED light bulbs suit your needs and pockets... you go green... I'm staying black for a while longer.

Quote from rs01 : You do realize that the high efficiency bulb costs over 10 times the cost of CFLs, right? Multiply the numbers with the number of bulbs you need to change in a typical house, if you want to be 'certified' green. In my experience of using over 50 CFLs in my home with varying amounts of usage, CFLs also run pretty welll for over 5 years, except about 10% that die prematurely. And as a consumer, I need to do all this homework to buy a light bulb? Compared to picking up a couple in samsclub/walgreens/homedepot while shopping for something else. If we do this sort of research for a common house hold bulb, just imagine the time we need to spend on researching when we buy a $1000 laptop... by the time we finish the research, there will be newer and better models and the cycle starts again. I'm talking about being practical too... When I posted my previous comment, I was pretty sure that you are going to quote a $20 - $25/piece LED bulb and say... look here is a higher efficiency LED bulb I think I spent enough time on this discussion already... so... if LED light bulbs suit your needs and pockets... you go green... I'm staying black for a while longer.

Quote from tadc : +1. Now if only more of those who were educated by the helpful posts would be grateful rather than argumentative in futile pursuit of saving face.

I think tadc said all that needs to be said.

Quote from brbubba : I think tadc said all that needs to be said.

double post

Quote from tantrik77 : LOL. You guys are funny, and obviously have no idea what you're talking about. 3000k is considered "romantic" lighting? Hahahaha look out, we have an "expert." All of you saying cool light is better for doing work and seeing details are absolutely incorrect. CRI (color rendering index) is the measure of a light source's ability to accurately reproduce colors. "Warmer" bulbs have higher CRI values than "cool" bulbs. As a result, light sources in the 2400k-3400k range are easier on your eyes, reproduce colors more accurately, and allow you to see finer details because of the increase in contrast. I play with LED modules/drivers/boards almost everyday (huge flashaholic) and look at bin charts constantly. Look here: http://www.cree.com/~/media/Files...ampXPG.pdf http://www.cree.com/~/media/Files...mpXPBL.pdf Which colors have the highest CRI? 2600-3200k.

All you are describing is how poorly some LED *reproduce* pure white light (and above) with proper color rendering. At least with fluorescents, 5000K T8 lamps are 14 percent more efficient than 4000K at light production and efficiency; this information is based on the Berman study from Berkeley Labs.

CRI is actually a measurement of color linearity compared to daylight. Daylight or 5000-6500K actually produces the highest color rendering across the full spectrum.

Contrast is a measurement of dynamic range of black and white. : the higher the contrast the greater ability to discern detail between dark and light. The light source for video is 6500K because it produces the greatest amount of CRI contrast and dynamics.

The problem is that undiffused LED produces direct glare that reduces pupil efficiency, CRI and contrast... the omnidirectional light of CFL doesn't have such a problem

I guess it depends on what you are trying to simulate with color temperature. The mood lighting of a romantic candlelit dinner is 1500-2500K. People get romantic about replicating LED and CFL replacements for incandescent at 2600-3000K. Some people like exact white at 3500k. I like to reproduce daylight at 5000k for closer to optimal efficiency and detail in the right applications.

Pupil efficiency is also 20-30 percent greater for daylight/5000k vs. cool white/4000k. If you were purchasing light to illuminate a library, 5000-6500K is the obvious choice, not your 3000k light.