Awesome LED lamp deal from HD

[sudsmaster]

Anybody else remember those "energy saver" discs from the 1980's? They were, as far as I can remember, little diodes that you stuck in the base of a lamp socket, under the bulb. I presume they functioned to screen out 1/2 of the AC voltage wave pattern, reducing the amount of energy delivered to the bulb. This was supposed to save energy. I recall using a few but not being particularly happy with the dimmer light they created.

 

[mattl]

Cree has some interesting fluorescent tube replacement options too.

 

Take a look at this review:

 

 

CREE's New Linear LED Fixture Review SL24 & SL40 - Fine Homebuilding

In the last 10 years Matt Risinger has installed a ton of Fluorescent lights in my houses. He thinks this new CREE fixture might finally signal the end of the T-5 Fluorescent Fixtures.

www.finehomebuilding.com

 

[supersuds]

They have those 40" tube replacement fixtures on Home Despot's website, and I have a perfect spot for them, but at $129.00 the payback time is going to be too lengthy for yours truly!

I remember those energy saver discs being advertised, but never knew of anyone using them. They sounded like a scam.

 

[tolivac]

For some of the HID sources I use and in many lighting handbooks-the reference sources are mentioned.Remember objects will look different under incandscent light as opposed to 6K blue sky noon sunlight.So you "assume" the light maker is using 2700K incandescent as the ref source?And yes,items and colors look diffrent under other sources, too.That is why the ref is important.So I take the CRI's on light bulb boxes with a grain of salt.The Lowes store here has a good display that shows many of the bulbs they sell lit so you can compare them.To sum it up you have to try the bulb for yourself to see if it meets your needs.

 

[sudsmaster]

Rex,

I'd be curious to know if you've ever found a consumer grade CFL or LED light with the CRI listed on the package and specifically linked to a stated "reference".

I know I haven't.

Can you scan such a package and post it? I'm not talking service manuals or mfg spec sheets. I'm talking retail packaging.

Most of the time, color temp is mentioned, but not CRI. Mention of CRI is the exception, not the rule.

But it's better than nothing.

And my local HD stores do not feature the CREE bulbs on powered up display. They do have some bulbs, but more often than not the LED bulbs are missing or never set up in the first place. Plus, with all the overhead skylight and cool white fluorescent lighting, it's sort of a bad environment to do any meaningful CRI estimation.

 

[tolivac]

Sudsmaster--that is the problem I have been trying to get across-Just WHAT are the light bulb makers comparing to?I don't know.Lucky the Lowes has some of the bulbs operating-even with the store lighting I can still get an idea at least what the light from the bulb looks like.Then that is why the CRI on the light box means NOTHING to me.It is good that the store in your area will allow you to try the bulb at home and if it doesn't meet your needs-you can return it.And if nothing elese-look up the bulb on the Internet-the maker can give more information than on the bulbs retail box.

 

[sudsmaster]

Rex,

Well, the CRI claim on a bulb or its packaging, or even on the mfg website, means a LOT to me.

And I can confirm again, that the TW series Cree bulb with the 93 CRI gives a very pleasant light in which ALL colors appear to be faithfully illuminated.

You might want to read the CREE website about their TW series bulbs. It contains a section that says CRI isn't everything, but not for the reason you state. Their point is that although some bulbs may boast a high CRI, the actual spectrum the bulb puts out has sharp peaks and valleys - which I understand is typical of CFL's. Their point is that their TW series bulbs compensate for this uneven spectrum with the neodymium coating on the outer glass envelope. They even provide a graph of the resultant light spectrum the bulb puts out. I'm not sure what more you need to know.

 

[sudsmaster]

Cree spectral notching for higher CRI...

From the linked PDF:

1. What is Color Rendering Index?
Color reproduction is an important characteristic of any type of lighting, including LED lighting. Color
reproduction is typically measured using the Color Rendering Index (CRI). CRI is measured on a scale up
to 100. The higher the CRI, the more accurately you will see the actual colors of objects that the bulb
illuminates (i.e. reds will look red).
Daylight has the highest CRI (~100), with a 2700K incandescent bulb being relatively close, and
fluorescent lighting being much less accurate (CRI 70-85). Certain types of specialized lighting, such as
sodium lights (street lights with yellow orange colored light) exhibit a relatively low CRI (as low as about
CRI 20 – 30). The Cree TW Series LED bulb has a high CRI of 93, unmatched for LED bulbs, making colors
look the way they were intended.

2. Is there such a thing as good CRI and poor CRI light?
The higher the CRI of a bulb, the more accurately you will see the color of objects illuminated by its light.
According to ENERGY STAR®, a bulb with a CRI of 80 is the minimum acceptable for ENERGY STAR
qualification. According to this standard, anything below 80 could be considered poor CRI light. A light
bulb with a CRI of 80 is a excellent general use bulb for the home.

4. So then ANY 80 CRI bulb is good?
Not exactly, not all 80 CRI bulbs are the same. LEDs produce light with broad a color spectrum, like
natural light has, while CFLs have very narrow bands of color, forcing your brain to fill in the missing
color gaps. Many people find this disturbing without even knowing why. Both may have a similar CRI,
but in fact the CFL light is a much poorer quality of light.

7. The Cree TW Series bulb achieves high CRI through spectral notching, what
does that mean?
The addition of neodymium in the glass of the bulb affects the LED light passing through the bulb to
create a “spectral notch”. A spectral notch is a portion of the color spectrum where the light is
attenuated thus forming a "notch" in the spectrum. By notching a portion of the yellow light, you get a
higher contrast between reds and greens which brings out the true colors of what is illuminated. What
remains is LED light that has a higher CRI.

http://www.creebulb.com/Content/downloads/product_info/TWseriesFAQ.pdf

 

[DADoES]

R30 vs. R40

 
Not having opportunity to visit Home Depot for Cree, I bought a couple GV-branded LED R30 floods (2700K, 650 lumens) for my office room.  There was previously an incandescent flood (which "poofed" this morn) and a CFL flood.

The problem I'm having with LED choices is that R40 LEDs are not commonly-offered and R30 doesn't fit nicely in my ceiling can fixtures, they're shorter and smaller diameter so don't fit flush to the ring and leave some of the interior exposed.

I see Home Depot offers a Philips R40 LED (dimmable) but $31.47 each.

1000Bulbs.com has a choice of R40 in six color temps in various brands.  Are these brands reputable?

 

[jetcone]

Wow

I learned a lot from this thread! 

I have been trying to express the concept of CRI as I saw some bulbs didn't quite fit my requirements as compared to the old incandescents. Now I understand what to look for- great thread!

 

 

 

[sudsmaster]

DADoES,

You might be able to use a socket extender to bring the LED spot lights flush with the ceiling. These add about an inch of length. I think you can find them still at OSH. Not sure about HD or Lowes.

 

[kb0nes]

Glenn,

Any chance your ceiling mounted cans have adjustable internal bulkheads? I have seen a few of these that allow the user to adjust the position of the socket bulkhead to suit various Trims and lamp options. You may be able to find different Trims to suit the smaller R30 also.

I have one of the Cree BR30 9.5w/650 lumen lamps and I like it a lot. It dims perfectly, although there is a step from minimum to off. These are a good deal for $19.95/ea @ The HD (if you can get them to fit your cans).

I looked over the 1000Bulbs.com site and their R40 offerings. I have heard of the TCP brand before, but none of the others. Unless a lamp is pretty cheap I don't take a chance on an unknown brand. Most of these are just Chinese products that are badged and sold here. Even with a known name I tend to shy away from the re-sellers, I'd rather buy something from the company making the LED's themselves if possible.

I did take a risk on an Ebay, no-name "China brand" 12 watt LED R style grow lamp. I was surprised at the heavy construction, its entirely aluminum. I took it apart when I got it and found the LED PCB wasn't screwed to the heatsink at all! Apparently the board in this lamp had different mounting hole positions. I drilled and tapped a couple new holes, and put a few Heli-coils in other holes and now its a solid lamp. My Boston Fern seems to like it a lot, CRI be dammed!

 

[sudsmaster]

Glenn,

I was just in Costco and they have BR40 LED floodlights, Feit brand, 100 watt equiv, for about $20 each. I think they use 18 watts. They are certainly a lot bigger than the Par 38 or BR30 lights.

 

[DADoES]

 
Thanks.  The nearest Costco is 90 miles round-trip, will aim to have a look there when next in the area.

 

[eronie]

Cree Led

I have quite a few Cree Led bulbs. I like them a lot! One thing i have noticed is that they dont attract BUGS !!! Porch lamps an torchers no bugs, dont know why, must be the CRI ?