While I understand that some people prefer a CCTs of4000K,
5000K, or even 6500K and respect those decisions, I also
believe that first time users of CFLs may be discouraged
from ever tying one again if they go to the store to by a
replacement for a normal incandescent lamp in their home and
return unknowingly with a 5000K CFL. Half of the bad press
for CFLs comes from what some people consider the "harsh"
light generated high CCT linear fluorescent lamps used in
offices.

Victor Roberts wrote:

While I understand that some people prefer a CCTs of4000K,
5000K, or even 6500K and respect those decisions, I also
believe that first time users of CFLs may be discouraged
from ever tying one again if they go to the store to by a
replacement for a normal incandescent lamp in their home and
return unknowingly with a 5000K CFL. Half of the bad press
for CFLs comes from what some people consider the "harsh"
light generated high CCT linear fluorescent lamps used in
offices.

I was talking to a electrician the other day after he had installed
fluorescent to replace a incandescent fixture in the break room. We got
to discussing CFLs, he mentioned he bought some for his house, but he
said that he didn't like how half his house has a 'bluish look' to it.

Granted, he probably didn't specialize in lighting, he just installed
the fixture and put whatever lights were on hand.


You would think the companies would realize this and market 2700K CFLs
as direct replacements for incandescents on the packaging.

Over this past weekend I purchased a few screw-base CFLs. I was
greatly disappointed to find out that it was hard or impossible
to determine the color temperature of the CFLs that I was trying
to purchase.

I was at Home Depot the other day and it was indeed marked on most of
the CFLs they sold. It wasn't on the front in the little "lumens/
watts/hours" box (where I think it should go), but it _was_ printed on
the back. The "nvision" brand had three different color temperatures
available and the packages were printed in different colors on a white
background. IIRC red was "soft white" and about 2800 K; green was
"bright white" and about 3500 K, and blue was "sunlight" or "daylight"
and about 5500 K.

Over this past weekend I purchased a few screw-base CFLs.
I was greatly disappointed to find out that it was hard or
impossible to determine the color temperature of the CFLs
that I was trying to purchase....

BTW, I've grown to dislike 2,700K CFLs and find the aforementioned
Sylvania a good choice for residential applications. The only 2,700K
CFL I like, and it happens to be my all time favorite, is GE's 2D.
For the life of me, I can't explain why I like this lamp so much more
than anything else, but there's something very pleasing about the
light it produces. Is there any rational explanation for this or do I
need to cut back on my happy pills?

Well, there is some physics driving the high CCT of CFLs. As
you know, in normal fluorescent lamps the mercury produces a
bit of blue and green light that is mixed with the slightly
yellow light from the phosphor to make white.

It turns out that the current density in most CFLs is so
high that they generate a lot of blue light. So much in
fact that many CFLs use only a two-component rare earth
phosphor mix instead of the normal three-component mix.
There is just too much blue to have any more coming from the
phosphor. (If the phosphor does have all three components,
then the blue component is reduced in small diameter lamps.)

On Mon, 11 Feb 2008 23:29:12 -0500 Victor Roberts <xxx@lighting-research.com> wrote:

| Over this past weekend I purchased a few screw-base CFLs.
| I was greatly disappointed to find out that it was hard or
| impossible to determine the color temperature of the CFLs
| that I was trying to purchase. And, I'm supposed to be an
| expert in this field!

As an engineer should should already know it's marketing issue.
They don't want to print all the specs on the box because it
confuses people (like those in the marketing department).

| None of the CFLs had a clear statement of the color
| temperature on the package. Some of CFLs had numbers such
| as 3000K or 5000K in small type buried among the other
| numbers on the ballast compartment. We all know that these
| refer to the color temperature, but what would these numbers
| mean to the typical consumer if they are not identified?

If the consumer does not know what color temperature is, which
describes nearly all of them, then it will mean nothing to them.
For all they know, it could be certification of Kosher compliance.

| While I understand that some people prefer a CCTs of4000K,
| 5000K, or even 6500K and respect those decisions, I also
| believe that first time users of CFLs may be discouraged
| from ever tying one again if they go to the store to by a
| replacement for a normal incandescent lamp in their home and
| return unknowingly with a 5000K CFL. Half of the bad press
| for CFLs comes from what some people consider the "harsh"
| light generated high CCT linear fluorescent lamps used in
| offices.

I'd prefer something around 2700K. I know I can get near that
with an incandescent bulb, and get a reasonably continuous
spectrum (at least no large gaps) as well. I only need that
for long term task lighthing (e.g. kitchen, shop, work bench).
All the rest can be [C]FL.


| I'm rather surprised and disappointed that Energy Star does
| not require color temperature to be predominately displayed
| on the box along with light output in Lumens and input power
| in Watts. I'm going to encourage Energy Star to add the CCT
| requirement to CFL packaging.

At least for "white" lights. I have not yet seen color bulbs in
CFL form, but it should not be hard to make them. I'm sure they
eventually will.

Many smaller lights can now be LED. Please include those in your
request for labeling requirements. I don't want some harsh blue
nightlight.

On Mon, 11 Feb 2008 23:29:12 -0500, Victor Roberts
xxx@lighting-research.com> wrote:

Over this past weekend I purchased a few screw-base CFLs.
I was greatly disappointed to find out that it was hard or
impossible to determine the color temperature of the CFLs
that I was trying to purchase....

Hi Victor,

Even when I'm sure I know what I'm getting I often prove myself wrong.
For example, Osram Sylvania's "Daylight Plus" CFLs have a colour
temperature of 3,500K and with a name like that I would fully expect
these lamps to be 5,000K, or perhaps higher given the "Plus"
designation. What marketing genius thought this up?

BTW, I've grown to dislike 2,700K CFLs and find the aforementioned
Sylvania a good choice for residential applications. The only 2,700K
CFL I like, and it happens to be my all time favorite, is GE's 2D.
For the life of me, I can't explain why I like this lamp so much more
than anything else, but there's something very pleasing about the
light it produces. Is there any rational explanation for this or do I
need to cut back on my happy pills?

Cheers,
Paul

On 12 Feb 2008 21:19:38 GMT, phil-news-nospam@ipal.net
wrote:

On Mon, 11 Feb 2008 23:29:12 -0500 Victor Roberts
xxx@lighting-research.com> wrote:

| Over this past weekend I purchased a few screw-base CFLs.
| I was greatly disappointed to find out that it was hard or
| impossible to determine the color temperature of the CFLs
| that I was trying to purchase. And, I'm supposed to be an
| expert in this field!

As an engineer should should already know it's marketing issue.
They don't want to print all the specs on the box because it
confuses people (like those in the marketing department).

Some of my best friends were marketing people :-)

| None of the CFLs had a clear statement of the color
| temperature on the package. Some of CFLs had numbers such
| as 3000K or 5000K in small type buried among the other
| numbers on the ballast compartment. We all know that these
| refer to the color temperature, but what would these numbers
| mean to the typical consumer if they are not identified?

If the consumer does not know what color temperature is, which
describes nearly all of them, then it will mean nothing to them.
For all they know, it could be certification of Kosher compliance.

Then we need to explain what color temperature is. I've
seen a nice chart that does that.

| While I understand that some people prefer a CCTs of4000K,
| 5000K, or even 6500K and respect those decisions, I also
| believe that first time users of CFLs may be discouraged
| from ever tying one again if they go to the store to by a
| replacement for a normal incandescent lamp in their home and
| return unknowingly with a 5000K CFL. Half of the bad press
| for CFLs comes from what some people consider the "harsh"
| light generated high CCT linear fluorescent lamps used in
| offices.

I'd prefer something around 2700K. I know I can get near that
with an incandescent bulb, and get a reasonably continuous
spectrum (at least no large gaps) as well. I only need that
for long term task lighthing (e.g. kitchen, shop, work bench).
All the rest can be [C]FL.


| I'm rather surprised and disappointed that Energy Star does
| not require color temperature to be predominately displayed
| on the box along with light output in Lumens and input power
| in Watts. I'm going to encourage Energy Star to add the CCT
| requirement to CFL packaging.

At least for "white" lights. I have not yet seen color bulbs in
CFL form, but it should not be hard to make them. I'm sure they
eventually will.

I'm not sure there is a big enough market for color CFLs.

Many smaller lights can now be LED. Please include those in your
request for labeling requirements. I don't want some harsh blue
nightlight.

Energy Star has a separate set of "certification"
requirements for LED-based luminaires and replacement lamps.

How about this one?

On Tue, 12 Feb 2008 21:12:38 -0400, Paul M. Eldridge
paul.eldridge@ns.sympatico.ca> wrote:

On Mon, 11 Feb 2008 23:29:12 -0500, Victor Roberts
xxx@lighting-research.com> wrote:

Over this past weekend I purchased a few screw-base CFLs.
I was greatly disappointed to find out that it was hard or
impossible to determine the color temperature of the CFLs
that I was trying to purchase....

Hi Victor,

Even when I'm sure I know what I'm getting I often prove myself
wrong. For example, Osram Sylvania's "Daylight Plus" CFLs have a
colour temperature of 3,500K and with a name like that I would fully
expect these lamps to be 5,000K, or perhaps higher given the "Plus"
designation. What marketing genius thought this up?

BTW, I've grown to dislike 2,700K CFLs and find the aforementioned
Sylvania a good choice for residential applications. The only 2,700K
CFL I like, and it happens to be my all time favorite, is GE's 2D.
For the life of me, I can't explain why I like this lamp so much more
than anything else, but there's something very pleasing about the
light it produces. Is there any rational explanation for this or do
I need to cut back on my happy pills?

Cheers,
Paul

Well, there is some physics driving the high CCT of CFLs. As
you know, in normal fluorescent lamps the mercury produces a
bit of blue and green light that is mixed with the slightly
yellow light from the phosphor to make white.

It turns out that the current density in most CFLs is so
high that they generate a lot of blue light. So much in
fact that many CFLs use only a two-component rare earth
phosphor mix instead of the normal three-component mix.
There is just too much blue to have any more coming from the
phosphor. (If the phosphor does have all three components,
then the blue component is reduced in small diameter lamps.)
The 2D is made in a rather large diameter tube, at least
measured by CFL standards. I believe it is T5 for most
wattages, while most lower power CFLs use T4 tubing or even
smaller. The larger diameter discharge in the 2D, along
with the length, reduces the current density, which in turn
reduces the amount of blue light produced by the discharge.
This allows a three-component rare earth phosphor to be used
which may lead to high quality light.

On Tue, 12 Feb 2008 21:12:38 -0400, Paul M. Eldridge
paul.eldridge@ns.sympatico.ca> wrote:

BTW, I've grown to dislike 2,700K CFLs and find the aforementioned
Sylvania a good choice for residential applications. The only 2,700K
CFL I like, and it happens to be my all time favorite, is GE's 2D.
For the life of me, I can't explain why I like this lamp so much more
than anything else, but there's something very pleasing about the
light it produces. Is there any rational explanation for this or do I
need to cut back on my happy pills?

Cheers,
Paul

Well, there is some physics driving the high CCT of CFLs. As
you know, in normal fluorescent lamps the mercury produces a
bit of blue and green light that is mixed with the slightly
yellow light from the phosphor to make white.

It turns out that the current density in most CFLs is so
high that they generate a lot of blue light. So much in
fact that many CFLs use only a two-component rare earth
phosphor mix instead of the normal three-component mix.
There is just too much blue to have any more coming from the
phosphor. (If the phosphor does have all three components,
then the blue component is reduced in small diameter lamps.)
The 2D is made in a rather large diameter tube, at least
measured by CFL standards. I believe it is T5 for most
wattages, while most lower power CFLs use T4 tubing or even
smaller. The larger diameter discharge in the 2D, along
with the length, reduces the current density, which in turn
reduces the amount of blue light produced by the discharge.
This allows a three-component rare earth phosphor to be used
which may lead to high quality light.