Something new for CFL ceiling lighting?
Sarah Austin
CFL's in the various rooms of this modular house.
These CFL's specify that a fixture be open, though, so as not to have a
heat buildup, I suppose.
The fixtures we have now are like this:
http://images.become.com/imageserver/s0/376930170-175-150-5-0/
clear ribbed bowl lights, but closed.
We'd rather not have to buy all new fixtures for the whole house, so I was
wondering if there were clear ribbed glass plates that we could replace
the bowls with, that would make open fixtures out of the existing ones,
and would let as much of the light out, as possible, too?
Even if they had something like a clear glass plate with leafed patterns
on it, and a hole in the middle to mount under the CFL's, it would be
great, but I cant find anything like that.
Suggestions?
Jeff Engel
Have you previewed the 5100K CFLs in the fixture that is currently
installed? Do you like the result? Most people would find 5100K to be
too cool. The CFLs are medium base screw in lamps? Every time you
replace this type of lamp, you replace the electronic ballast. With a
pin base CFL, the ballast is part of the fixture, not replaced each time
a lamp expires. Over time, this should be the cheaper option.
There's not much hope in replacing the glass, making it open. This
isn't an especially expensive fixture, so it's no great loss to start
with a dedicated CFL fixture. You are making a decision that will be a
constant contentment or an irritation. The cost isn't really the big
issue, it's how satisfied you are with the result. Shop at a lighting
showroom or distributor that sells to the building trades and
electricians. You'll get good advice and more options than the Home
Depot aisle can offer.
Victor Roberts
Why are you switching to 5100K or above? Is this a decision
you made after studying different color temperatures, or was
this suggested or mandated by someone else?
The incandescent lamps you are taking out have a color
temperature of about 2700K. 5100K is close to the color
temperature of the sun, and most people find that a lamp
this "blue" make skin tones look terrible.
As for the fixture, there are fixtures with "bowl" type
glass refractors on the bottom, that are still open at the
top. They might be an acceptable alternative to the fixture
you have.
--
Vic Roberts
http://www.RobertsResearchInc.com
http://www.cflfacts.com
To reply via e-mail:
replace xxx with vdr in the Reply to: address
or use e-mail address listed at the Web site.
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It may not be used in any publication or posted on any Web
site without written permission.
Wes
news:Xns9CA4D3492C7D9Sn...@216.196.97.142...
Sarah:
I'm a sales rep in the lighting industry. Trust me when I tell you, you can
replace the fixtures for less that you could find replacement glass. And
actually, as far as the UL label is concerned (not that you would care) but
the fixture is NOT approved to use a different glass. (Yeah I know people
do that, but technically they shouldn't).
Personally I wouldn't be concerned about heat build up... 27 watts really
isn't anything compared to the heat the fixture would contain with
incandescent.
However, are you SURE you want to go to 5100K?
Honestly, 2700 or perhaps 3500, but that's going to be a very harsh blue
light....
Just my thoughts.
Wes
TKM
"Wes" <we...@prodigy.net> wrote in message
news:DaGdncThCtssX0rX...@giganews.com...
Good advice from Wes. CFLs that are less heat tolerant are marked that they
have to be used in open fixtures. Most CFLs, however, are not marked and
they can be used in either enclosed or open fixtures. UL tests such CFLs
for electrical and fire safety in enclosures.
Your chances of getting a good CFL go up if you buy those marked as Energy
Star.
Terry McGowan
Sarah Austin
Sarah Austin
I thought full spectrum was supposed to be best for people and animals.
Rusty
"Sarah Austin" <SAu...@pndfnospam.com> wrote in message
news:Xns9CA5EB1C92643Sn...@216.196.97.142...
Ah-ha! Full spectrum is just a fancy marketing term. Search this group and
you will see past discussions on full spectrum.
Wikipedia also has a good summary:
http://en.wikipedia.org/wiki/Full-spectrum_light
A good CRI (Color Rendering Index,) is all that really matters. Those yucky
cheap cool white T12s fluorecents have a CRI around 65, whereas the best
tri-phosphor fluorescent lights get around 90ish CRI. A CRI of 100 would be
an incandescent/halogen light.
JB
term when applied to fluorescents.
JB
Joe
<SAu...@pndfnospam.com> wrote:
[snip]
>
>I thought full spectrum was supposed to be best for people and animals.
Sarah,
I just want to expand on Rusty's good observation.
If you don't understand the full lighting picture, you can think of
sunlight as having a fairly even mix of all possible "colors" (with
some greater emphasis on the more blue end). Fluorescent lights, in
contrast, have a relatively few spikes of individual "color groups",
that blend together to give an appearance of white light. The problem
is that colors that do not occur in the aforementioned "color groups"
are not illuminated as well as other colors, and therefore seem
deficient to the observer. Skin tones, for example, are rather
complex, and are very difficult to illuminate evenly with many
fluorescents.
The CRI index is a figure that takes our human perception of colors
into account; that's why it is a much better gauge of how well a given
lamp will perform in your home.
And yeah, 5100K is way too blue for the inside of a house - and I say
that even with my individual preference for higher color temp lights,
especially in my shop.
Another comment on using compacts inside enclosed housings - my
(admittedly limited) experience is that most of the cheaper CFs cannot
tolerate even their own heat output without good air circulation. The
cheapest part - the ballast - is what fails. I'd like to know of some
brands that can be used inside closed fixtures other than ceiling
cans.
Joe
Please remember that the above comments are geared to a less
technically-inclined person, and are in no way the "real scientific
deal".
Rusty
news:hb957f$h8g$1...@aioe.org...
fluorescent lighting is just a marketing gimmick that implies fluorescent
lights that approximates the feel of sunlight via a high color temp and
hopefully a high CRI. You would still need a high lux (brightness) and a
single point of light to get the true sunlight "feel", otherwise the high
color temp just seems "off" when used in a domestic situation.
Just as an example, I once had a dance teacher who operated a basement dance
studio that was lit entirely with cheap cool white (4100K @ 67CRI) T12
fluorescent tubes. It honestly felt like an old warehouse with a wooden
floor and mirrors. She said that she had heard of "Full Spectrum" lights
and wanted them installed.
I knew that those full spectrum lights would be way too expensive to replace
40 tubes, so I opted to replace the tubes with SPEC35 (3500K @ 85CRI)
tubes. The cost was only about twice as much compared to the old tubes. The
difference was like night and day, and she was very happy with the result.
Joe
OK, Rusty's reply to his post also made me want to clarify my own
comments:
In the studies I've seen, the "best" color temperature is dependant on
the overall level of light. The more blue cast of high CCT lamps looks
better (less bad?) in a brightly lit (really brightly lit)
environment. As the light level goes down - and interior lighting is
never as bright as sunlight on a sunny day - a warmer (lower) color
temperature appears more pleasing. All of this is within the photopic
range, too. So, for your application, you will need the high-CRI
lamps, and a lower color temperature, as well. Think of something less
than 3500K. You might want to compare a variety of CFs against a
halogen lamp of the same relative brightness to get an idea of the
color-rendering characteristics of your choices. Not real scientific,
but you stand a better chance of pleasing your own tastes. Hang some
artwork and put a person in the light for comparison.
Joe
Sarah Austin
Sarah Austin
http://www.amazon.com/Compact-Fluorescent-Spiral-Equivalent-
Spectrum/dp/B000NJAAQM
23 Watt Compact Fluorescent Spiral Light Bulb, 100 Watt Equivalent,
5500K Full Spectrum (High C.R.I.)
Product Features
* CRI: 90
* Average Life Hours: 10,000
* Base: Medium (Standard)
* Initial Lumens: 1200
Rusty
news:Xns9CA4D3492C7D9Sn...@216.196.97.142...
Something occurred to me, you never really mentioned if the energy savings
was a factor.
If it's not, then might I suggest so=called daylight incandescent bulbs?
they achieve similar results by using slightly tinted glass. The bulbs are
a slight pinkish/purple/blue in color and supposedly filter out the yellow
hues associated with regular incadescent bulbs.
Brands to consider:
GE Reveal
Sylvania Daylight
Phillips Natural Light and Natural Light Plus
*some of the off brands refer to these daylight bulbs as 'full spectrum'
which is misused still, a regular incandescent bulb is already full
spectrum.
Sarah Austin
> On Fri, 16 Oct 2009 00:06:39 -0500, Sarah Austin
><SAu...@pndfnospam.com> wrote:
>
> [snip]
>>
>>I thought full spectrum was supposed to be best for people and
animals.
>
> Sarah,
>
> I just want to expand on Rusty's good observation.
>
> If you don't understand the full lighting picture, you can think of
> sunlight as having a fairly even mix of all possible "colors" (with
> some greater emphasis on the more blue end).
I get that part. I read "Health & Light" in the late 70's and started
using Vita-Lites back then.
> Fluorescent lights, in
> contrast, have a relatively few spikes of individual "color groups",
> that blend together to give an appearance of white light.
But does the body really care about spikes, or the average spectral
distribution?
> The problem
> is that colors that do not occur in the aforementioned "color groups"
> are not illuminated as well as other colors, and therefore seem
> deficient to the observer. Skin tones, for example, are rather
> complex, and are very difficult to illuminate evenly with many
> fluorescents.
Yet they have these photo lights that are supposed to be "true color".
http://www.alzodigital.com/online_store/replacement_lamps.htm
27W CFL light bulb
45W CFL bulb
These special Photo CFL (Compact Fluorescent Light) bulbs have a natural
"daylight" balanced color temperature of 5500K. These bulbs are shipped
with our ALZO "Cool-Lite" kits. These special energy saving bulbs are
"flicker free" and specifically designed for digital photo imaging. They
produce a soft diffuse light with CRI of 91 and bulb life is exceptional
at about 10,000 hours.
> The CRI index is a figure that takes our human perception of colors
> into account; that's why it is a much better gauge of how well a given
> lamp will perform in your home.
Agreed. But I havent seen any 5500k bulbs that didn't have a CRI of at
least 89.
> And yeah, 5100K is way too blue for the inside of a house - and I say
> that even with my individual preference for higher color temp lights,
> especially in my shop.
But I've been using Vita-Lites since the late 70's, over my desk, even
over the bed for reading. ( just turn them off awhile before bedtime )
> Another comment on using compacts inside enclosed housings - my
> (admittedly limited) experience is that most of the cheaper CFs cannot
> tolerate even their own heat output without good air circulation. The
> cheapest part - the ballast - is what fails. I'd like to know of some
> brands that can be used inside closed fixtures other than ceiling
> cans.
I'd like to see some developed with totally clear plates ( ok, maybe cut
flower patterns ) and that are open.
Sarah Austin
> In the studies I've seen, the "best" color temperature is dependant on
> the overall level of light. The more blue cast of high CCT lamps looks
> better (less bad?) in a brightly lit (really brightly lit)
> environment. As the light level goes down - and interior lighting is
> never as bright as sunlight on a sunny day - a warmer (lower) color
> temperature appears more pleasing. All of this is within the photopic
> range, too. So, for your application, you will need the high-CRI
> lamps, and a lower color temperature, as well. Think of something less
> than 3500K.
Is that even possible? From what I see, color temp is roughly bound with
CRI. Am I wrong?
> You might want to compare a variety of CFs against a
> halogen lamp of the same relative brightness to get an idea of the
> color-rendering characteristics of your choices. Not real scientific,
> but you stand a better chance of pleasing your own tastes. Hang some
> artwork and put a person in the light for comparison.
Well I agree on not trending blue, but what are the options if I want a
pure white light with a high CRI in CFL indoor lighting?
Sarah Austin
> I knew that those full spectrum lights would be way too expensive to
> replace 40 tubes, so I opted to replace the tubes with SPEC35 (3500K
> @ 85CRI) tubes. The cost was only about twice as much compared to
> the old tubes. The difference was like night and day, and she was
> very happy with the result.
Ok, now we're getting somewhere.
So what I'd really like, is to get away from bluish light, and get pure
white in a CFL with as high a CRI as possible.
Now 3500k seems on the yellowish end, but might feel warmer for a dance
studio, but like I said, I'd prefer pure white.
Here's an interesting site that shows the feel of things:
http://www.brite-lite.com/Products/Technical/Color_Temp.html
The bottom chart
"THE INFLUENCE OF COLOR TEMPERATURE ON MOOD AND LIGHTING APPLICATIONS"
I like the "neat clean efficient" of white without yellow or blue tones,
but what do I look for in CFL that has that, AND a high CRI?
Sarah Austin
> Something occurred to me, you never really mentioned if the energy
> savings was a factor.
Absolutely. This if for home and home office and they're talking about
this "cap and trade" stuff.
�Under my plan of a cap and trade system, electricity rates would
necessarily skyrocket.� � Barack Obama
> If it's not, then might I suggest so=called daylight incandescent
> bulbs?
Arent incandescent bulbs going to be banned by 2014?
http://www.wnd.com/news/article.asp?ARTICLE_ID=59298
Ken
<SAu...@pndfnospam.com> wrote:
> > In the studies I've seen, the "best" color temperature is dependant on
> > the overall level of light. The more blue cast of high CCT lamps looks
> > better (less bad?) in a brightly lit (really brightly lit)
> > environment. As the light level goes down - and interior lighting is
> > never as bright as sunlight on a sunny day - a warmer (lower) color
> > temperature appears more pleasing. All of this is within the photopic
> > range, too. So, for your application, you will need the high-CRI
> > lamps, and a lower color temperature, as well. Think of something less
> > than 3500K.
>
> Is that even possible? From what I see, color temp is roughly bound with
> CRI. Am I wrong?
My old fluorescent tubes
2700K CRI 95 63 lm/W
http://tekniken.se/misc/philips_tld36w-92.jpg
http://tekniken.se/misc/philips_tld.png
Sarah Austin
Ken
<SAu...@pndfnospam.com> wrote:
I don't think so. People only like to by cheap things today.
Rusty
> "Rusty" <russju...@netscape.net> wrote :
>
>> Something occurred to me, you never really mentioned if the energy
>> savings was a factor.
>
> Absolutely. This if for home and home office and they're talking about
> this "cap and trade" stuff.
>
> "Under my plan of a cap and trade system, electricity rates would
>
>> If it's not, then might I suggest so=called daylight incandescent
>> bulbs?
>
> Arent incandescent bulbs going to be banned by 2014?
>
> http://www.wnd.com/news/article.asp?ARTICLE_ID=59298
>
>
If you are unable to find good CFLs that work well in enclosed fixtures,
then you may need to replace the fixure. I know of similar fixtures that
use pin-based CFLs with a separate ballast, which is nice because the tube
is what burns out most often, and you don't waste a perfectly good ballast.
This one made by Lithonia is similar to what your picture shows:
http://www.lithonia.com/product/resi.aspx?pt=Decorative+%2f+Residential&family=Sheffield+Flush+-+Semi-Flush&sfamily=8287&model=283
The catch is it comes with 4-pin 2700K CFLs, which wouldn't be your
preference, so you would need to look for similar CFLs that are 4100K with
80+ CRI
Rusty
I chose 3500K for the dance studio because it matched the rest of the
school, which had been retrofitted and upgraded to T8 3500K lights
I guess it comes down to the "eye of the beholder." I prefer 3500K which is
generally considered neutral, but it does come off having a warmish-pink in
my experience. You sound like 4100K would be your preference, as long as it
has a good CRI.
Many home improvement stores will have a light box comparison display so you
can get a sense how each color temp compares to each other. Sometimes they
will use marketing names for the comparison IE:
Natural/Neutral/Daylight/etc. which can be annoying as each maker uses
different terms to describe the different color temps.
Sarah Austin
Is it that, or is it something about needing a larger surface to
generate the higher CRI along with lower kelvin?
Sarah Austin
I'm even rethinking 4100k now. It looks like the purest white is around
3500k on some charts. It's just confusing because 4100k is termed "cool
white" and 3500k appears yellowish in some charts and is called "neutral
white" in others.
http://www.patmullins.com/img/colortempchartorig.jpg
http://www.bulbs.com/eSpec.aspx?ID=14938&Ref=Category&RefId=13
Sarah Austin
http://www.mmlights.com/bird%20lights.html
I had no idea Philips had one with a CRI of 98.
Don Klipstein
<I SNIP to the point of "full spectrum">
>I thought full spectrum was supposed to be best for people and animals.
Please keep in mind that "full spectrum" does not have a definition
accepted by IESNA or CIE or any organization that the "lighting industry"
gives much weight to.
Over the past many years, I have even at times sensed slight reluctance
to allowance of acceptance of an "industry standard for full spectrum",
"in my words based on what I sensed", "lest some of the quacksters gain
support by an industry standard for their quackery".
For most home usage of light sources, I would stick with "warmer"
(lower) color temperatures, towards 2700 K for "more warm" and towards
3500 K for "whiter-shade-of-warm" or "barely warm enough to usually not
appear pure white". 4000-4100 K is "slightly warmish side, but usually
looks "white rather than warm", often "dreary grayish" unless illumination
level gets to around a kilolux (or maybe 1.1-2) typical of brighter office
areas, classrooms, and brighter retail environments.
I also look for color rendering index at least 82, the usual CRI of CFLs
that achieve right to use the "Energy Star" logo and/or are of "Big 3"
brands, as well as a majority of others better than "dollar store stool
specimens". And fluorescents achieving around 90 CRI usually have their
minor color-distortions in a "slightly dulling direction", while ones with
CRI 82-86 tend to have their color distortions majority in a "direction of
more-vivid". Fluorescents achieving or claiming CRI more than 86 also
have a high rate of doing so with a significant compromise in light
output.
- Don Klipstein (d...@misty.com)
I.N. Galidakis
[snip]
> I'm even rethinking 4100k now. It looks like the purest white is around
> 3500k on some charts. It's just confusing because 4100k is termed "cool
> white" and 3500k appears yellowish in some charts and is called "neutral
> white" in others.
>
> http://www.patmullins.com/img/colortempchartorig.jpg
> http://www.bulbs.com/eSpec.aspx?ID=14938&Ref=Category&RefId=13
In general, the triphosphor FLs or CFLs with a CCT of 4,000-4,100K are an
excellent choice for indoor lighting. Combined with tungsten halogen I'd say
that they provide a most excellent illumination.
Although the triphosphor FLs and CFls are not really "full-spectrum" (see Don's
answer for example) their spectrum is balanced enough to be pleasant to the
human eye, perhaps even as pleasant as small tungsten-halogen lights.
Since lighting levels generally affect the overall result, I'd suggest long
linear FLs with such a CCT for superb results.
Going to higher CCTs, (in excess of 4,500-5,000K) won't give you any additional
benefit in terms of quality of light, even if the CRI is higher, because you'd
need very high illumination levels in order to benefit from such a CCT and/or
CRI.
I don't think you can achieve this with a few small CFLs, which, if their CCT is
of higher order than 4,500-5,000K, they will appear bluish and will most likely
be "coldish" and generally annoying for indoor usage.
--
Ioannis
Sarah Austin
> In <Xns9CA5EB1C92643Sn...@216.196.97.142>, Sarah A.
> wrote:
>
><I SNIP to the point of "full spectrum">
>
>>I thought full spectrum was supposed to be best for people and
>>animals.
>
> Please keep in mind that "full spectrum" does not have a definition
> accepted by IESNA or CIE or any organization that the "lighting
> industry" gives much weight to.
>
> Over the past many years, I have even at times sensed slight
> reluctance
> to allowance of acceptance of an "industry standard for full
> spectrum", "in my words based on what I sensed", "lest some of the
> quacksters gain support by an industry standard for their quackery".
>
> For most home usage of light sources, I would stick with "warmer"
> (lower) color temperatures, towards 2700 K for "more warm" and
> towards 3500 K for "whiter-shade-of-warm" or "barely warm enough to
> usually not appear pure white". 4000-4100 K is "slightly warmish
> side, but usually looks "white rather than warm", often "dreary
> grayish" unless illumination level gets to around a kilolux (or maybe
> 1.1-2) typical of brighter office areas, classrooms, and brighter
> retail environments.
Ah ok, thanks.
> I also look for color rendering index at least 82, the usual CRI of
> CFLs
> that achieve right to use the "Energy Star" logo and/or are of "Big
> 3" brands, as well as a majority of others better than "dollar store
> stool specimens". And fluorescents achieving around 90 CRI usually
> have their minor color-distortions in a "slightly dulling direction",
> while ones with CRI 82-86 tend to have their color distortions
> majority in a "direction of more-vivid". Fluorescents achieving or
> claiming CRI more than 86 also have a high rate of doing so with a
> significant compromise in light output.
Oh ok, didn't know that, thanks Don.
Sarah Austin
I know, I'm trying out a couple of Ecosmart "True Color" 27w 5500k 1400
lumen compact fluorescents in the living room, without the bowl on the
fixture ( Home Depot 409 162 ) and they seem both bluish an dim at the
same time.
Sarah Austin
> In general, the triphosphor FLs or CFLs with a CCT of 4,000-4,100K
> are an excellent choice for indoor lighting.
Whew, trying to find a compact fluorescent spiral with those specs, on
Google, just made me dizzy. Too much extraneous stuff pops up with it.
I.N. Galidakis
The results will be better if you search for LINEAR, LONG fluorescents, with
those specs, in the range of 30-60 Watts. Not COMPACT fluorescents.
--
Ioannis
I.N. Galidakis
[snip]
> The results will be better if you search for LINEAR, LONG fluorescents, with
> those specs, in the range of 30-60 Watts. Not COMPACT fluorescents.
For example:
http://www.lightbulbsdirect.com/page/001/CTGY/T12
Since these are marketed as "full-spectrum" (left column), it's a pretty safe
bet that they are triphosphor technology fluorescents.
Look closely at around the 4,100-4,200 K items.
--
Ioannis
Victor Roberts
<SAu...@pndfnospam.com> wrote:
>Victor Roberts <x...@lighting-research.com> wrote :
>
>> On Wed, 14 Oct 2009 21:46:08 -0500, Sarah Austin
>><SAu...@pndfnospam.com> wrote:
>>
>>>We're switching over from incandescent to 27 watt dual 5100k or 5500k
>>>CFL's in the various rooms of this modular house.
>>>
>>>These CFL's specify that a fixture be open, though, so as not to have
>>>a heat buildup, I suppose.
>>>
>>>
>>>The fixtures we have now are like this:
>>>http://images.become.com/imageserver/s0/376930170-175-150-5-0/
>>>
>>>clear ribbed bowl lights, but closed.
>>>
>>>We'd rather not have to buy all new fixtures for the whole house, so
>>>I was wondering if there were clear ribbed glass plates that we could
>>>replace the bowls with, that would make open fixtures out of the
>>>existing ones, and would let as much of the light out, as possible,
>>>too?
>>>
>>>Even if they had something like a clear glass plate with leafed
>>>patterns on it, and a hole in the middle to mount under the CFL's, it
>>>would be great, but I cant find anything like that.
>>>
>>>Suggestions?
>>
>> Why are you switching to 5100K or above? Is this a decision
>> you made after studying different color temperatures, or was
>> this suggested or mandated by someone else?
>>
>> The incandescent lamps you are taking out have a color
>> temperature of about 2700K. 5100K is close to the color
>> temperature of the sun, and most people find that a lamp
>> this "blue" make skin tones look terrible.
>
>It's full spectrum though, right? Most natural?
"Full spectrum" is marketing hype. It is an undefined term,
that is used by different companies to mean different
things. 2700K incandescent lamps are also "full spectrum"
using at least one of the reasonable definitions of this
term.
--
Vic Roberts
http://www.RobertsResearchInc.com
http://www.cflfacts.com
To reply via e-mail:
replace xxx with vdr in the Reply to: address
or use e-mail address listed at the Web site.
This information is provided for educational purposes only.
It may not be used in any publication or posted on any Web
site without written permission.
Victor Roberts
wrote:
[snip]
>Good advice from Wes. CFLs that are less heat tolerant are marked that they
>have to be used in open fixtures. Most CFLs, however, are not marked and
>they can be used in either enclosed or open fixtures. UL tests such CFLs
>for electrical and fire safety in enclosures.
>
>Your chances of getting a good CFL go up if you buy those marked as Energy
>Star.
>
>Terry McGowan
I disagree re: the effect of enclosed fixtures on CFLs.
Certainly, any CFL not marked for use only in open fixtures
will be safe in an enclosed fixture, all CFLs have reduced
life when operated in higher ambient temperature. Therefore,
when using smaller enclosed fixtures, the power rating of
the CFL should be kept as low as possible to avoid reducing
the life of the CFL.
Victor Roberts
<SAu...@pndfnospam.com> wrote:
>Joe <see_re...@sig.lin> wrote :
>
>
>> In the studies I've seen, the "best" color temperature is dependant on
>> the overall level of light. The more blue cast of high CCT lamps looks
>> better (less bad?) in a brightly lit (really brightly lit)
>> environment. As the light level goes down - and interior lighting is
>> never as bright as sunlight on a sunny day - a warmer (lower) color
>> temperature appears more pleasing. All of this is within the photopic
>> range, too. So, for your application, you will need the high-CRI
>> lamps, and a lower color temperature, as well. Think of something less
>> than 3500K.
>
>Is that even possible? From what I see, color temp is roughly bound with
>CRI. Am I wrong?
Yes, you are wrong. Color temperature and CRI and
completely independent. A normal incandescent lamp has a
CRI very close to 100, yet has a color temperature close to
2700K. The sun also has a CRI close to 100, but a color
temperature of 5780K.
Victor Roberts
wrote:
You can certainly buy high quality CFL, but not in the
"dollar store."
Victor Roberts
<SAu...@pndfnospam.com> wrote:
No. Surface area has nothing to do with either CRI or CCT.
Victor Roberts
<russju...@netscape.net> wrote:
>"Sarah Austin" <SAu...@pndfnospam.com> wrote in message
>news:Xns9CA6EB166F841Sn...@216.196.97.142...
>> "Rusty" <russju...@netscape.net> wrote :
>>
>>> Something occurred to me, you never really mentioned if the energy
>>> savings was a factor.
>>
>> Absolutely. This if for home and home office and they're talking about
>> this "cap and trade" stuff.
>>
>> "Under my plan of a cap and trade system, electricity rates would
>> necessarily skyrocket." - Barack Obama
>>
>>> If it's not, then might I suggest so=called daylight incandescent
>>> bulbs?
>>
>> Arent incandescent bulbs going to be banned by 2014?
>>
>> http://www.wnd.com/news/article.asp?ARTICLE_ID=59298
>>
>>
>
>If you are unable to find good CFLs that work well in enclosed fixtures,
>then you may need to replace the fixure. I know of similar fixtures that
>use pin-based CFLs with a separate ballast, which is nice because the tube
>is what burns out most often, and you don't waste a perfectly good ballast.
And ... it is the life of the ballast that is reduced by the
high temperatures inside the fixture. By using pin-base
lamps, and placing the ballast outside the part where the
lamp is located, these fixture provide mush longer ballast
life. Plus, they are more environmentally friendly because,
as you have noted, you do not throw away the ballast every
time you change the lamp.
>This one made by Lithonia is similar to what your picture shows:
>http://www.lithonia.com/product/resi.aspx?pt=Decorative+%2f+Residential&family=Sheffield+Flush+-+Semi-Flush&sfamily=8287&model=283
>
>The catch is it comes with 4-pin 2700K CFLs, which wouldn't be your
>preference, so you would need to look for similar CFLs that are 4100K with
>80+ CRI
--
Ken
<x...@lighting-research.com> wrote:
>>>>>> In the studies I've seen, the "best" color temperature is
>>>>>> dependant on the overall level of light. The more blue cast of
>>>>>> high CCT lamps looks better (less bad?) in a brightly lit (really
>>>>>> brightly lit) environment. As the light level goes down - and
>>>>>> interior lighting is never as bright as sunlight on a sunny day -
>>>>>> a warmer (lower) color temperature appears more pleasing. All of
>>>>>> this is within the photopic range, too. So, for your application,
>>>>>> you will need the high-CRI lamps, and a lower color temperature,
>>>>>> as well. Think of something less than 3500K.
>>>>>
>>>>> Is that even possible? From what I see, color temp is roughly
>>>>> bound with CRI. Am I wrong?
>>>>
>>>> My old fluorescent tubes
>>>> 2700K CRI 95 63 lm/W
>>>> http://tekniken.se/misc/philips_tld36w-92.jpg
>>>> http://tekniken.se/misc/philips_tld.png
>>>
>>> But not in CFL?
>>
>> I don't think so. People only like to by cheap things today.
>
> You can certainly buy high quality CFL, but not in the
> "dollar store."
Yes. It's hard to buy high quality today.
Victor Roberts
One way to find what you need is to first search on the
manufacturers' web sites: GE, Philips, Sylvania, TCP,
Maxlite, etc. These sites usually allow you to you can
search, or at least select, by style, power and color
temperature. Then, when you find a model you like, Google
that model number to find a place to buy it.
Sarah Austin
Apparently. I'm about to give up on spiral compact fluorescents, they're
so limited in choices.
So another question then; Do they make any dual T8 fixtures that are
open and let the light out all over the room, instead of blocking it? (
decent looking ones, besides shop lights :)
Sarah Austin
Wow, the octron look interesting:
http://www.lightbulbsdirect.com/page/001/PROD/T8%2BOctron/F32T8835
Cheap too!
I.N. Galidakis
[snip]
> Wow, the octron look interesting:
>
> http://www.lightbulbsdirect.com/page/001/PROD/T8%2BOctron/F32T8835
I will not make any specific recommendations, except to outline two cases:
1) If the space you intend to illuminate will host detailed work which depends
on good color quality, go with 4,100K.
2) If the space you intend to illuminate will host a more relaxed environment,
such as a resting place or living room, consider a little lower CCT, such as
3,500K.
If I remember well, you said something about a dancing floor?
For this I would recommend a higher CCT of 4,100K. Lower CCTs are for resting.
To achieve an honest color balance, you'd need around 8-10 T-8 30-32W linear
fluorescents, for a total of 300-320W. There are 8-shaped T-8 fixtures which can
accomodate this many lamps. For even better color balance, surround your
T-8/T-12 fixture with tungsten-halogen torchiers near the walls, in the 10-30 W
range.
> Cheap too!
"Cheap" isn't the issue. Quality of illumination is.
--
Ioannis
Rusty
news:1255940237.941913@athprx04...
>
> If I remember well, you said something about a dancing floor?
>
difference, not related to the color temp. I also wanted to make the
differnce very apparent since the lights were those crap 67CRI 4100K T12s,
so keeping the same color temp wouldn't have been as obvious.
That was about 7 years ago when I was on the maintenance crew, and since
then they have changed dance teachers, and probably went back to installing
those low CRI T12s again. Ah well.
> For this I would recommend a higher CCT of 4,100K. Lower CCTs are for
> resting.
> To achieve an honest color balance, you'd need around 8-10 T-8 30-32W
> linear
> fluorescents, for a total of 300-320W. There are 8-shaped T-8 fixtures
> which can
> accomodate this many lamps. For even better color balance, surround your
> T-8/T-12 fixture with tungsten-halogen torchiers near the walls, in the
> 10-30 W
> range.
>
Sarah did mention pet birds which should be a factor.
Don Klipstein
>"JB" <n...@spam.net> wrote :>> news:Xns9CA5EAEAE9AACSn...@216.196.97.142...
>>> Victor Roberts <x...@lighting-research.com> wrote :
>> hate that term when applied to fluorescents.
>> JB
>
>Even Vita-Lites?
"Full Spectrum" has no definition accepted by any significant industry
standards organization.
Meanwhile, "Vita-Lites" are high-CRI flatter-spectrum halophosphate
lamps, with CRI around 91 IIRC. I do think of those as "full spectrum".
I would prefer "850" color triphosphor lamps such as Philips Ultralume
5000, whose CRI is 84 IIRC, for 3 reasons:
1. The "Vita Lites" and similar lamps have light output being
significantly compromised, while "850" lamps do not.
2. The color distortions of the "Vita Lites" and similar lamps, although
generally small, are mostly in the direction of making colored objects
appear darker and duller.
3. Major-brand triphosphor lamps cost less than specialty brand extra-
high-CRI ones and specialty brands that tout "full sectrum".
Meanwhile, if overall color of the light is matched and
scotopic/photopic ratio is matched (in this case they will be close),
then all known photoreceptors in the human eye will be stimulated in
roughly the same ratios by both lamps. The likely-existing cirtopic
receptors will be stimulated a little less by triphosphor light than by
an equal amount of halophosphate light of the same color, but it appears
to me that the triphosphor will outweigh this due to producing more light.
And, the need to stimulate the likely-existing cirtopic receptors,
and how much need there is, is still under debate. Meanwhile, I would
not pay extra for health claims of "full spectrum" lamps.
And in the likely event high color temp. lamps in home use achieves a
"stark" or "dreary gray" effect, I would use ones of lower color temp.
(3500K or less) despite making the light less like that of "natural
daylight".
- Don Klipstein (d...@misty.com)
Don Klipstein
in part:
>http://www.amazon.com/Compact-Fluorescent-Spiral-Equivalent-
>Spectrum/dp/B000NJAAQM
>
>23 Watt Compact Fluorescent Spiral Light Bulb, 100 Watt Equivalent,
>5500K Full Spectrum (High C.R.I.)
>Product Features
>
> * CRI: 90
> * Average Life Hours: 10,000
> * Base: Medium (Standard)
> * Initial Lumens: 1200
Three things to watch out for with this 23 watt CFL having CRI of 90:
1. The phosphor is probably a "broadband variant" of halophosphate
phosphor. In the intense irraiation of a CFL, I consider it likely to
fade faster than fluorescent lamp phosphors usually do.
Keep in mind that phosphor life in narrower, more intense fluorescent
lamps was the main driving force for development of triphosphors.
2. Usual initial output of 23 watt CFLs with the usual CRI of 82 is 1600
lumens in low color temps. and around 1500 lumens in high color temps.
3. If this CFL indeed has a halophosphate phosphor, its color
distortions, even though generally small, will be mostly in the direction
of making colored objects darker and duller. The color distortions of
a usual triphosphor CFL, even though greater, are still generally minor
and largely in the direction of making colored objects brighter and more
vivid.
- Don Klipstein (d...@misty.com)
Don Klipstein
in part:
>Joe <see_re...@sig.lin> wrote :
>
>> In the studies I've seen, the "best" color temperature is dependant on
>> the overall level of light. The more blue cast of high CCT lamps looks
>> better (less bad?) in a brightly lit (really brightly lit)
>> environment. As the light level goes down - and interior lighting is
>> never as bright as sunlight on a sunny day - a warmer (lower) color
>> temperature appears more pleasing. All of this is within the photopic
>> range, too. So, for your application, you will need the high-CRI
>> lamps, and a lower color temperature, as well. Think of something less
>> than 3500K.
>
>Is that even possible? From what I see, color temp is roughly bound with
>CRI. Am I wrong?
CRI and color temp. are completely independent of each other. CRI of
100 is achieved by definition of CRI by incandescent lamps, even 2700 K
and less, as well as by daylight - such as light from overcast sky at
around 6000 K or even more bluish varieties of daylight.
- Don Klipstein (d...@misty.com)
Don Klipstein
wrote in part:
>We also have pet birds here too, and this is what they say about lighting:
>
>http://www.mmlights.com/bird%20lights.html
>
>I had no idea Philips had one with a CRI of 98.
With about 2/3 the light output of their lamps with CRI of 84, and even
with a CRI of 98 they have a spiky spectrum. The usual CRI is "Ra8",
which tests only eight colors, and I suspect this lamp is "tuned for this
test".
Meanwhile, if birds do indeed have tetrachromatic vision, then CRI
figures for lamps with irregular spectra or less UV than is present in
same quantity and color of daylight do not apply for birds.
- Don Klipstein (d...@misty.com)
Don Klipstein
wrote in part:
>Yet they have these photo lights that are supposed to be "true color".
>
>http://www.alzodigital.com/online_store/replacement_lamps.htm
>
>27W CFL light bulb
>
>45W CFL bulb
>
>These special Photo CFL (Compact Fluorescent Light) bulbs have a natural
>"daylight" balanced color temperature of 5500K. These bulbs are shipped
>with our ALZO "Cool-Lite" kits. These special energy saving bulbs are
>"flicker free" and specifically designed for digital photo imaging. They
>produce a soft diffuse light with CRI of 91 and bulb life is exceptional
>at about 10,000 hours.
Like I said elsewhere in this thread, I would be concerned about how
the likely-halophoaphate phosphor fares during 10,000 hours in the intense
irradiation of a CFL. Light output is probably also less than with CFL of
same wattage and CRI of 82.
>> The CRI index is a figure that takes our human perception of colors
>> into account; that's why it is a much better gauge of how well a given
>> lamp will perform in your home.
>
>Agreed. But I havent seen any 5500k bulbs that didn't have a CRI of at
>least 89.
N:Vision brand "Daylight" at Home Depot is 5500 K with the
usual-for-CFLs CRI of 82.
- Don Klipstein (d...@misty.com)
Don Klipstein
>"Sarah Austin" <SAu...@pndfnospam.com> wrote in message
>> We're switching over from incandescent to 27 watt dual 5100k or 5500k
>> CFL's in the various rooms of this modular house.
>>
>> These CFL's specify that a fixture be open, though, so as not to have a
>> heat buildup, I suppose.
>>
>>
>> The fixtures we have now are like this:
>> http://images.become.com/imageserver/s0/376930170-175-150-5-0/
>>
>> clear ribbed bowl lights, but closed.
>>
>> We'd rather not have to buy all new fixtures for the whole house, so I was
>> wondering if there were clear ribbed glass plates that we could replace
>> the bowls with, that would make open fixtures out of the existing ones,
>> and would let as much of the light out, as possible, too?
>>
>> Even if they had something like a clear glass plate with leafed patterns
>> on it, and a hole in the middle to mount under the CFL's, it would be
>> great, but I cant find anything like that.
>>
>> Suggestions?
>>
>
>was a factor.
>
>a slight pinkish/purple/blue in color and supposedly filter out the yellow
>hues associated with regular incadescent bulbs.
>
>Brands to consider:
>
>GE Reveal
>Sylvania Daylight
>Phillips Natural Light and Natural Light Plus
>
>*some of the off brands refer to these daylight bulbs as 'full spectrum'
>which is misused still, a regular incandescent bulb is already full
>spectrum.
The above three incandescents are not the same. The GE "Reveal" and
"Enrich" incandescents have glass bulbs tinted bluish with a neodymium
compound, causing the spectrum to have a strong but narrow dip in the
yellow. As far as I know, the Philips and Sylvania ones with bluish glass
have the glass tinted by something much more broadband, with a broadband
reduction of wavelengths from yellow-green to deep red.
Neodymium bulbs are popular for their color distortions caused by
narrowband elimination of yellow light. The neodymiun filtering achieves
a spectrum that has more red and more green than 100-CRI light of the same
color temperature. The visual result is red and green objects being
illuminated more vividly. Yellow objects are largely not distorted in
color and brightness, since they largely reflect/pass all wavelengths from
green through red.
- Don Klipstein (d...@misty.com)
Don Klipstein
wrote:
>"Rusty" <russju...@netscape.net> wrote :
>
>> Something occurred to me, you never really mentioned if the energy
>> savings was a factor.
>
>this "cap and trade" stuff.
>
>�Under my plan of a cap and trade system, electricity rates would
>
>> If it's not, then might I suggest so=called daylight incandescent
>> bulbs?
>
>
>http://www.wnd.com/news/article.asp?ARTICLE_ID=59298
USA's upcoming incandescent lamp ban has a wide range of exceptions,
amounting to loophole sufficiency to reroute the Mississippi River
through.
http://members.misty.com/don/incban.html
- Don Klipstein (d...@misty.com)
Don Klipstein
wrote in part:
>I'm even rethinking 4100k now. It looks like the purest white is around
>3500k on some charts. It's just confusing because 4100k is termed "cool
>white" and 3500k appears yellowish in some charts and is called "neutral
>white" in others.
>
>http://www.patmullins.com/img/colortempchartorig.jpg
>http://www.bulbs.com/eSpec.aspx?ID=14938&Ref=Category&RefId=13
3500 K is sometimes referred to as a "neutral white", and Sylvania has
used "Daylight" for that color. (I have yet to see other fluorescent
lamp manufacturers use "daylight" to refer to color temp. less than 5000
K or over 7500 K.) I find 3500 K to be a "warm white but whiter".
4100 K is the "usual cool white color" that offices, classrooms, and
hospitals are usually illuminated with. I find it to be "plain white".
I do usually find 4100 K to be extremely slightly yellowish when
compared with midday sunlight, which I estimate to usually be around
4400-4600 K in Philadephia PA USA, although varying with time of day and
time of year and Philadelphia's widely-varying air quality.
Higher color temp. usually requires higher illumination level to "look
good". I often find even as low as 4100 K to have a "dreary gray effect"
if illumination level is less than several hundred lux.
5000 K is a "crisp cool" color that I usually find to be either an icy
pure white but sometimes an extremely slightly bluish shade of white, and
usually slightly bluish when lower color temp. ("warmer") light sources
are also around.
5500 K I usually find to be very slightly bluish, less often "pure
white". I also usually find it difficult to get 5500 K to "look good"
in home use, due to "dreary grayish effect" that in my experience takes at
least a few hundred lux (usually 1,000-plus lux) of illumination to fix.
6500 K lamps normally appear to me to be a slightly bluish shade of
white, almost never pure white - although my computer monitor usually
appears close to pure white to me. 6000 K lighting can appear to me to be
a "pure white", especially if from overcast sky, but usually appears to me
slightly bluish.
What I also see with 6500 K lighting is that it takes thousands of lux
of illumination for it to "look good".
- Don Klipstein (d...@misty.com)
Don Klipstein
I would look in 4 places if you are in the USA:
1. True Value hardware stores, where I see 4100 K spirals of their house
brand.
2. Target - I have seen GE 4100 K spirals there.
3 and 4: Lowes and Home Depot, especially Lowes.
- Don Klipstein (d...@misty.com)
Don Klipstein
My experience in USA is that best place to get those is
electrical/lighting supply shops that contractors go to.
I often find T8 (1 inch diameter) 4100 K 17 and 32 watt fluorescents at
home centers, and they are triphosphor, but they usually have the lower
grade phosphor formulation with CRI in the upper 70's - GE's SP41 and
741 by other brands.
I prefer the SPX41/841 "better formulation", with CRI generally around
84 for T8 lamps.
As for a good 4100 K triphosphor fluorescent in T12 (1.5 inch
diameter) sizes and wattages, there is Philips Ultralume 4100 - a little
hard to get.
There is also "Deluxe Cool White" in 4-foot T12, 4100 K with CRI around
90, but reduced light output and color distortions in the same dulling
direction (though much milder) as with "ordinary cool white".
- Don Klipstein (d...@misty.com)
Don Klipstein
>"I.N. Galidakis" <morp...@olympus.mons> wrote :
>
>> I.N. Galidakis wrote:
>> [snip]
>>
>>> The results will be better if you search for LINEAR, LONG
>>> fluorescents, with those specs, in the range of 30-60 Watts. Not
>>> COMPACT fluorescents.
>>
>> For example:
>>
>> http://www.lightbulbsdirect.com/page/001/CTGY/T12
>>
>> Since these are marketed as "full-spectrum" (left column), it's a
>> pretty safe bet that they are triphosphor technology fluorescents.
>>
>> Look closely at around the 4,100-4,200 K items.
>
>Wow, the octron look interesting:
These come in both 741 and 841, with 841 having better color rendering.
- Don Klipstein (d...@misty.com)
Don Klipstein
>On Thu, 15 Oct 2009 21:07:01 -0400, "TKM" <non...@no.net> wrote:
>
>[snip]
>
>>Good advice from Wes. CFLs that are less heat tolerant are marked that they
>>have to be used in open fixtures. Most CFLs, however, are not marked and
>>they can be used in either enclosed or open fixtures. UL tests such CFLs
>>for electrical and fire safety in enclosures.
>>
>>Your chances of getting a good CFL go up if you buy those marked as Energy
>>Star.
>
>Certainly, any CFL not marked for use only in open fixtures
>will be safe in an enclosed fixture,
Except for the dollar store stool specimens with mention of UL listing
being usually absent, and maybe suspicious if present.
I find CFLs of "dollar store brands" generally objectionable, for many
reasons. My experience with these has ones with light output claims
having a 100% rate of falling short, most of these to have either a
halophosphate phosphor or mostly-halophosphate phosphor (low CRI in warmer
colors), sometimes claiming warm color when color temp. is 6500-7500 K,
and an above-average rate of spectacular failures.
- Don Klipstein (d...@misty.com)
TKM
"Don Klipstein" <d...@manx.misty.com> wrote in message
news:slrnhdpli...@manx.misty.com...
To say that incandescent bulbs are "going to be banned by 2014" is not
correct. There are plenty of exemptions as Don has pointed out; but even
the standard household bulbs which are the targets of the legislation in
both California and, more recently, on the Federal level are not being
"banned". They are being required to become more efficient. California
starts with the 100 watt bulb on 1/1/2011. It will have to be rated for 72
watts, 1000 hours and a lument output of 1490-2500 lumens compared to the
100 watt bulb of today which is rated for about 1700 lumens. That will be a
challenge to bulb manufacturers, but some have already announced products
which will meet the requirements.
If household incandescent lamps disappear, that will likely result when the
"Tier II" requirements of 45 lumens/watt kick in in California beginning
1/1/2018.
Terry McGowan
I.N. Galidakis
> "I.N. Galidakis" <morp...@olympus.mons> wrote in message
> news:1255940237.941913@athprx04...
>>
>> If I remember well, you said something about a dancing floor?
>>
> That was me. The issue I was pointing out was how a good CRI can make a
> difference, not related to the color temp. I also wanted to make the
> differnce very apparent since the lights were those crap 67CRI 4100K T12s,
> so keeping the same color temp wouldn't have been as obvious.
My apologies. Memory failure. This thread has gotten a bit longish and I lost
track of who said what.
[snip]
> Sarah did mention pet birds which should be a factor.
For birds and other pets such as reptiles my recommendation would be High
Pressure Mercury corrected. The latter give off very small amounts of longwave
UV which seems to be needed for many pets. I am pretty sure reptiles need it,
but I am not so sure about birds.
--
Ioannis
Don Klipstein
Many reptiles have some need for UVB, maybe nearly-UVB shorter wave end
of UVA, probably for producing Vitamin D. I suspect that dietary
supplement of Vitamin D will work, but I have yet to look into finding if
it has been worked out how much Vitamin D supplement to feed reptiles in
order to negate need for exposure to UVB or nearly-UVB part of UVA. It
can get easier to put reptiles and lamps in enclosures made of transparent
material that blocks such UV, including most glass, and most cast grades
and all UB-blocking grades of acrylic, and most possibly all
polycarbonate.
As for birds - fow now, I have some sensation that this is hype. I have
low expectation that birds have a 4th and ultraviolet photopic vision
sensor unlike mammals, even though insects do. Although most birds fly,
all of them are in the same phylum that all mammals are in, with a very
different phylum-wide model for eyes from the model used by the phylum
that includes all insects. (I am aware that one gene that determines
whether to build eyes and where on the body to build eyes is the same for
both phyla, though these two phyla have eyes that are different in many
including very fundamental ways.)
As a result, I am suspicious that the claim by someone selling lamps
that birds have a UV-specific 4th color-sensing retinal photoreceptor is
along the lines of what I sense as "hype" by many marketing "full
spectrum" lamps, including many that have what I consider to be health
claims of "full spectrum".
Do we now need to web-search for whether or not birds actually have an
insect-like 4th color receptor in the UVA range?
- Don Klipstein (d...@misty.com)
TKM
No small diameter lamps (T8 or less) are likely to use the old
halo-phosphors to improve color rendering because of rapid light output
depreciation due to high current density as Vic pointed out some months
back. Rather, rare-earth phosphors are used to fill in the spectral gaps so
that high-CRI lamps have four or more phosphors instead of the usual three.
Such lamps are tricky to build because of color-control problems and, of
course, they are more expensive.
Terry McGowan
Sarah Austin
White" 30 watt spirals, 2100 lumens, 3500k.
http://www.homedepot.com/Lighting-Fans-Light-Bulbs/EcoSmart/h_d1/N-
5yc1vZ1xhfZas2zZ4b8/R-100663852/h_d2/ProductDisplay?langId=-1&storeId=
10051&catalogId=10053
Here's how one looks next to an Ecosmart 5500k 27w
http://lakewoodcolorado.net/Sarah/DSCN5318.JPG
It's hard to tell whether the 5500k is just too blue, or the 3500k is just
too yellow.
What about a pure white light?
But these ARE so bright that you cant look at them, just not what I'd call
"white". They have no CRI that I can tell, on the packaging or the web
page.
Sarah Austin
Non-issue to me, I shop Home Depot, not dollar stores.
IMO dollar stores sell things for far more than a dollar, that probably
only cost THEM a dollar.
Sarah Austin
Another aspect is that a lot of these lamps will cut back light output
when they're warm, wont they?
Sarah Austin
> Sarah Austin wrote:
> [snip]
>
>> Wow, the octron look interesting:
>>
>> http://www.lightbulbsdirect.com/page/001/PROD/T8%2BOctron/F32T8835
>
> I will not make any specific recommendations, except to outline two
> cases:
>
> 1) If the space you intend to illuminate will host detailed work
> which depends on good color quality, go with 4,100K.
>
> 2) If the space you intend to illuminate will host a more relaxed
> environment, such as a resting place or living room, consider a
> little lower CCT, such as 3,500K.
>
> If I remember well, you said something about a dancing floor?
Not me, that was someone else.
Sarah Austin
Birds need some UVA and UVB for vitamin D synthesis, I understand.
Victor Roberts
Good point. None of my comments or suggestions EVER refer
to "dollar store" lamps. I have never purchased one and
probably never will.
--
Vic Roberts
http://www.RobertsResearchInc.com
http://www.cflfacts.com
To reply via e-mail:
replace xxx with vdr in the Reply to: address
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This information is provided for educational purposes only.
It may not be used in any publication or posted on any Web
site without written permission.
Victor Roberts
<SAu...@pndfnospam.com> wrote:
>I went to Home Depot and had a look, and found some Ecosmart "Bright
>White" 30 watt spirals, 2100 lumens, 3500k.
>
>http://www.homedepot.com/Lighting-Fans-Light-Bulbs/EcoSmart/h_d1/N-
>5yc1vZ1xhfZas2zZ4b8/R-100663852/h_d2/ProductDisplay?langId=-1&storeId=
>10051&catalogId=10053
>
>Here's how one looks next to an Ecosmart 5500k 27w
>http://lakewoodcolorado.net/Sarah/DSCN5318.JPG
>
>
>
>It's hard to tell whether the 5500k is just too blue, or the 3500k is just
>too yellow.
It's impossible to tell from a photograph. The human
eye/brain system makes adjustments in real time that the
camera cannot capture.
>What about a pure white light?
What do you mean by "pure white"? White light comes in
various color temperatures. They are all "pure white."
>But these ARE so bright that you cant look at them, just not what I'd call
>"white". They have no CRI that I can tell, on the packaging or the web
>page.
--
Victor Roberts
No more than any other CFL. If properly designed, they
should run at peak output and efficacy when fully warmed up.
Sarah Austin
> On Tue, 20 Oct 2009 17:00:37 -0500, Sarah Austin
><SAu...@pndfnospam.com> wrote:
>
>>I went to Home Depot and had a look, and found some Ecosmart "Bright
>>White" 30 watt spirals, 2100 lumens, 3500k.
>>
>>http://www.homedepot.com/Lighting-Fans-Light-Bulbs/EcoSmart/h_d1/N-
>>5yc1vZ1xhfZas2zZ4b8/R-100663852/h_d2/ProductDisplay?langId=-1&storeId=
>>10051&catalogId=10053
>>
>>Here's how one looks next to an Ecosmart 5500k 27w
>>http://lakewoodcolorado.net/Sarah/DSCN5318.JPG
>>
>>
>>
>>It's hard to tell whether the 5500k is just too blue, or the 3500k is
>>just too yellow.
>
> It's impossible to tell from a photograph. The human
> eye/brain system makes adjustments in real time that the
> camera cannot capture.
I see that now. ( no pun intended :)
I turned on these new Bright Whites and a 40W 2700k one that I put in
the dining room drop-down lamp, and then compared with the 5500k ones in
the other rooms, and in context, the 2700k does look yellowish, the
3500k does look mostly bright white, with a little yellow, and the 5500k
of course look bluish.
>>What about a pure white light?
>
> What do you mean by "pure white"? White light comes in
> various color temperatures. They are all "pure white."
Argh. :)
Well what I mean, is that if you look at these spectrum charts of color
temp, like the one at
http://www.soslightbulbs.com/colortemperaturechart.aspx
there's a small region of plain white that seems neither yellowish or
bluish. Pure white?
Rusty
"Victor Roberts" <x...@lighting-research.com> wrote in message
news:b1osd5dun17vn8vl8...@4ax.com...
I was visiting family in Houston TX, and went shopping with my dad at a
dollar store, he saw some CFLs and gave them a shot.
Bad choice, I installed them in the laundry room and they were the most
HIDEOUS color temp with a bad CRI I have ever seen, way worse than those
blasted cheap cool white T12s I keep on mentioning.
Victor Roberts
<SAu...@pndfnospam.com> wrote:
I have lost your original intent. Do you want a "white"
light for some specific purpose, such as color matching
fabrics? In that case the question of the best "white"
light has one answer, or set of answers.
However, if you want a color temperature that looks pleasing
in a particular environment, the question becomes far more
complicated. Noon time sunlight looks great outside.
However, as others have pointed out, if you use EXACTLY that
same color inside at typical indoor illumination levels,
most people would say it looks terrible, and also that it
looks "too blue." On the other hand, many people define
the color of tungsten halogen incandescent lamps as "crisp
white," yet this source has a color temperature near 3000K,
and would look yellowish with compared to sunlight or
photographed by a camera that is set for "daylight"
compensation.
I use a camera to document evidence for various legal cases
I am involved with. I know that, unless I am very careful,
objects that look one way to my eye can look very different
when they are captured by the camera. The human brain has a
way of compensating for the average color temperature of a
scene, while a camera does not, unless specifically
instructed by the human user.
Don Klipstein
wrote:
Chances are the CRI is the 82 that is usual of CFLs, other than the few
claiming more and the dollar store stool specimens.
- Don Klipstein (d...@misty.com)
Don Klipstein
You are reminding me of most "warm color" dollar store CFLs. My
experience is that if they are warm color rather than bluish-daylight
color, they are usually some sort of purplish-beigeish-pinkish with CCT
eyeball-estimate around 2900-3000 K and with a spectrum similar to that of
"old tech warm white" (whose CRI is 53).
Some in packages saying "soft warm white light" are actually
bluish-daylight - with CRI probably in the mid to maybe upper 70's.
Including a Telstar one that lasted 3 minutes, then filled my bedroom with
smoke and had an orange glow in its ballast housing that persisted until I
turned it off.
- Don Klipstein (d...@misty.com)
Sarah Austin
> On Tue, 20 Oct 2009 23:03:18 -0500, Sarah Austin
><SAu...@pndfnospam.com> wrote:
>
>>Victor Roberts <x...@lighting-research.com> wrote :
>>
>>> On Tue, 20 Oct 2009 17:00:37 -0500, Sarah Austin
>>><SAu...@pndfnospam.com> wrote:
>>>
>>>>I went to Home Depot and had a look, and found some Ecosmart
>>>>"Bright White" 30 watt spirals, 2100 lumens, 3500k.
>>>>
>>>>http://www.homedepot.com/Lighting-Fans-Light-Bulbs/EcoSmart/h_d1/N-
>>>>5yc1vZ1xhfZas2zZ4b8/R-100663852/h_d2/ProductDisplay?langId=-1&storeI
>>>>d= 10051&catalogId=10053
I see what you're saying.
Well we have two main purposes for lighting here inside the house.
First is our pet birds, and in lieu of scientific evidence to the
contrary, which I'm working on finding out about now ( see other thread
) we use T8 Vita-Lites over their cages and they seem to be doing well
with it. ( anecdotal, I understand, for now )
Then we may have been operating under a false premise that I picked up
in the 70's in "Health and Light", that the same Vita-Lites are the best
indoor lighting for people's health. This thread has thrown that into
doubt now, and I'm keeping an open mind.
So I started experimenting a little. For indoor lighting outside of the
bedrooms, we want good reading light, and a bright cheerful look. Vita-
Lites, in retrospect, dont seem to provide that, they do look bluish.
Whether they also help with "SAD" is also questionable and I'm keeping
an open mind on that too. Maybe just getting outside in the winter is
best?
Of course our cockatoo wont do that. He's 1.6 lbs and can crack a walnut
shell in 1 second, and if he doesnt want to go outside, we dont push
him. :)
He doesnt like it cold, like it's getting outside now in the Denver
area.
So I'm interested in that aspect.
For our lighting, I was experimenting recently and listing to some of
your thoughts here ( which I thank you for! ) and came across that
Bright White Ecosmart compact fluorescent from Home Depot ( 30 watt /
125 watt equiv, 2100 lumens, 3500k, no CRI rating ) and we like that
spectrum for our home offices ( we have two ). It's nice to read by, a
little on the warm side but just cozy, not too yellow or orange like
2700k seems.
But then I thought about the CRI aspect y'all mentioned here, so I did
some digging around.
I found what appear to be a very nice bulb in the 3500k, which I just
ordered a case of, for the two offices ( business expense ):
http://www.businesslights.com/tcp-xhl-32w-3500k-85-cri-t8-fluorescent-
lamp-case25-p-2060.html
TCP XHL 32W 3500K 85 CRI T8 Fluorescent Lamp case/25
[691231]
$47.50
TCP XHL 32W 3500K 85 CRI T8 Fluorescent Lamp case/25
TCP F32T8/835 3500K 85 CRI 3400 Lumens Fluorescent Lamp case/25
* On sale why quantities last
* 31032835XHL F32T8/835 Lamp Specifications
* 32 watts
* Color Temperature: 3500� Kelvin
* Color Rendering: 85 CRI
* MOL: 48 inches
* Initial Lumens: 3400
* Mean Lumens: 3200
* Average Rated Life: 24,000 hrs
* Minimum starting temperature: 10�C
* Low Mercury - TCLP Compliant
* Designed to operate on Instant Start ballasts
The CRI of 85 seems about as high as I can find in 3500k. The lumen
output looks great and the price is very nice.
In fact we may put fixtures in the bedrooms for these, for such things
as overhead light for cleaning, reading and finding things, while we
keep incandescents or 2700k compact fluorescents for bedtime winding
down, for the yellow spectrum.
Don Klipstein
on the Philips TL950 lamp with need for correction:
>In <Xns9CA7CA416F673Sn...@216.196.97.142>, Sarah Austin
>wrote in part:
>
>>We also have pet birds here too, and this is what they say about lighting:
>>
>>http://www.mmlights.com/bird%20lights.html
>>
>>I had no idea Philips had one with a CRI of 98.
>
> With about 2/3 the light output of their lamps with CRI of 84, and even
>with a CRI of 98 they have a spiky spectrum. The usual CRI is "Ra8",
>which tests only eight colors, and I suspect this lamp is "tuned for this
>test".
Someone called me on this, and forwarded some documention including a
spectral power distribution curve for a Philips 941 lamp similar to their
TL950 lamp that I was commenting on.
I check out the TL950 in:
http://www.prismaecat.lighting.philips.com/ecat/Light/
ApplicationRouter.aspx?fh_secondid=927870095002_1&fh_view_size
=10000&fh_start_index=0&fh_eds=%c3%9f&fh_location=%2f%2fprof%2fus_US%
2fcategories%3c%7bfnppla%7d%2fcountries%3e%7bus_US%7d%2fstatus%3e%7bact%
7d%2fcategories%3c%7bc_err2fnppla_1830_np01lmp%7d%2fcategories%3c%
7bc_0022fnppla_1857_up_f%7d%2fcategories%3c%7bc_0012fnppla_1890_up_ft8%
7d%2f_rated_lamp_wattage%3e%7bplc_352%7d&fh_refview=lister&tab=&family=
&&left_nav=us_en&
Leading to, I hope the spectral power distribution is here:
http://www.prismaecat.lighting.philips.com/ecat/Light/Details.aspx?
fh_eds=%u00df&fh_location=%2f%2fprof%2fus_US%2fcategories%3c%7bfnppla%7d%
2fcountries%3e%7bus_US%7d%2fstatus%3e%7bact%7d%2fcategories%3c%7bc_
err2fnppla_1830_np01lmp%7d%2fcategories%3c%7bc_0022fnppla_1857_up_f%7d%
2fcategories%3c%7bc_0012fnppla_1890_up_ft8%7d%2f_rated_lamp_wattage%3e%
7bplc_352%7d&fh_refview=lister&fh_secondid=927870095002_1&fh_start_index=
0&fh_view_size=10000&left_nav=us_en&tab=images
This page has an option for images ready to change from "product photo"
to either of two options for spectral power distribution.
It is a lot less spiky than I remember. Unless it has changed, I am
remembering a spectrum of a different lamp achieving at least mid-90's CRI
with a spiky spectrum. The latter sounds likely to me, because it's been
a few years since I last checked this out - and accordingly I correct
myself on the spikyness/smoothness of the Philips TL950 lamp.
The phosphor output is indeed published to be a smooth broad band,
higher where strong mercury lines are lacking - in the blue-green and
more-visible portion of mid-red, lower where strong mercury lines are
present or where human vision has low sensitivity.
- Don Klipstein (d...@misty.com)
Sarah Austin
> http://www.prismaecat.lighting.philips.com/ecat/Light/
> ApplicationRouter.aspx?fh_secondid=927870095002_1&fh_view_size
>=10000&fh_start_index=0&fh_eds=%c3%9f&fh_location=%2f%2fprof%2fus_US%
> 2fcategories%3c%7bfnppla%7d%2fcountries%3e%7bus_US%7d%2fstatus%3e%7bac
> t% 7d%2fcategories%3c%7bc_err2fnppla_1830_np01lmp%7d%2fcategories%3c%
> 7bc_0022fnppla_1857_up_f%7d%2fcategories%3c%7bc_0012fnppla_1890_up_ft8
> %
> 7d%2f_rated_lamp_wattage%3e%7bplc_352%7d&fh_refview=lister&tab=&family
> = &&left_nav=us_en&
Just a suggestion for future reference:
http://tinyurl.com/
:)
Victor Roberts
Are you are talking about the relative contribution to the
spectrum from the atomic emission lines vs. the contribution
from the phosphor? If so, the height of the spikes in the
SPD that come from atomic emission lines, relative to the
emission from the phosphor is totally meaningless - unless
the data is provided on the spectral resolution of the
spectrometer used.
I've taken data like this myself using a spectrometer with
variable slit width. The relative height of the atomic
emission lines (the mercury lines in an Ar-Hg discharge) to
the height of the phosphor output is a strong function of
the slit width, and hence the spectral resolution of the
spectrometer. By adjusting the slit width, the lines can be
made to "disappear" into the phosphor background, or, on the
other hand, the phosphor can be made to virtually disappear
while the atomic emission lines remain.
The reason is quite clear. The atomic emission lines are
narrower than the resolution of any normal spectrometer,
while the phosphor is a broad band source. As the slit
width is varied, the absolute peak intensity of the atomic
emission lines will remain constant, while the absolute peak
intensity of the phosphor emission will vary directly with
the spectral resolution. So, as the silt width is
decreased, the phosphor intensity decreases relative to the
intensity of the atomic emission lines. On the other hand,
as the slit width is increased, the absolute intensity of
the atomic emission lines is again constant, but the
absolute intensity of the phosphor emission goes up, and,
for large spectral resolutions, can equal the intensity of
the atomic emission lines.
Don Klipstein
>On Sat, 24 Oct 2009 04:47:28 +0000 (UTC), d...@manx.misty.com
>(Don Klipstein) wrote:
>
>>In <slrnhdpkj...@manx.misty.com>, I, Don Klipstein, wrote in part
>>on the Philips TL950 lamp with need for correction:
>>
<SNIP part of what Sarah Austin said to edit for space - she said in part:>
>>>>I had no idea Philips had one with a CRI of 98.
>>>
>>> With about 2/3 the light output of their lamps with CRI of 84, and even
>>>with a CRI of 98 they have a spiky spectrum. The usual CRI is "Ra8",
>>>which tests only eight colors, and I suspect this lamp is "tuned for this
>>>test".
>>
>> Someone called me on this, and forwarded some documention including a
>>spectral power distribution curve for a Philips 941 lamp similar to their
>>TL950 lamp that I was commenting on.
(Now, I look back and see that forwarded to me was SPD of a TLD/940 lamp.)
>> I check out the TL950 in:
>>
<SNIP huge URL that I mentioned for this lamp in Philips online catalog>
>>
>> Leading to, I hope the spectral power distribution is here:
>>
<SNIP a similar huge URL that I mentioned>
>>
>> This page has an option for images ready to change from "product photo"
>>to either of two options for spectral power distribution.
>>
>> It is a lot less spiky than I remember. Unless it has changed, I am
>>remembering a spectrum of a different lamp achieving at least mid-90's CRI
>>with a spiky spectrum. The latter sounds likely to me, because it's been
>>a few years since I last checked this out - and accordingly I correct
>>myself on the spikyness/smoothness of the Philips TL950 lamp.
>>
>> The phosphor output is indeed published to be a smooth broad band,
>>higher where strong mercury lines are lacking - in the blue-green and
>>more-visible portion of mid-red, lower where strong mercury lines are
>>present or where human vision has low sensitivity.
>>
>> - Don Klipstein (d...@misty.com)
>
>Are you are talking about the relative contribution to the
>spectrum from the atomic emission lines vs. the contribution
>from the phosphor?
No. The spectrum that I remembered, apparently incorrectly for Philips
TL950, had not only spikes from mercury lines, but also moderately narrow
to almost-linelike-narrow phosphor bands like the TL850 has, only 2 or 3
more of them including one in the red (longer than 611 nm, maybe around
630 nm) and one in the yellow.
<Back to what Vic wrote - in short and in my words, if I got it right,
explanation that tall spikes in a spectral power distribution curve may
amount to not a whole lot of spectral content if the spectrometer has
narrow resolution>
- Don Klipstein (d...@misty.com)