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| Don Klipstein... |
 Posted: Mon Oct 19, 2009 10:26 am |
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In <Xns9CA6C981F59B9SntzldfrdSntzldfrdco at (no spam) 216.196.97.142>, S. Austin wrote:
[quote]"JB" <nil at (no spam) spam.net> wrote :
"Sarah Austin" <SAustin at (no spam) pndfnospam.com> wrote in message
news:Xns9CA5EAEAE9AACSntzldfrdSntzldfrdco at (no spam) 216.196.97.142...
Victor Roberts <xxx at (no spam) lighting-research.com> wrote :
On Wed, 14 Oct 2009 21:46:08 -0500, Sarah Austin
SAustin at (no spam) 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?
Sadly they will be nothing remotely like 'full spectrum'. I do so
hate that term when applied to fluorescents.
JB
Even Vita-Lites?
[/quote]
"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 (don at (no spam) misty.com) |
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| Don Klipstein... |
| Posted: Mon Oct 19, 2009 10:38 am |
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In <Xns9CA6C9FF93885SntzldfrdSntzldfrdco at (no spam) 216.196.97.142>, S. Austin wrote
in part:
[quote]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
[/quote]
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 (don at (no spam) misty.com) |
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| Don Klipstein... |
| Posted: Mon Oct 19, 2009 10:47 am |
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In <Xns9CA6E97A3521CSntzldfrdSntzldfrdco at (no spam) 216.196.97.142>, S. Austin wrote
in part:
[quote]Joe <see_real_one at (no spam) 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?
[/quote]
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 (don at (no spam) misty.com) |
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| Don Klipstein... |
| Posted: Mon Oct 19, 2009 10:56 am |
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In <Xns9CA7CA416F673SntzldfrdSntzldfrdco at (no spam) 216.196.97.142>, Sarah Austin
wrote in part:
[quote]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.
[/quote]
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 (don at (no spam) misty.com) |
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| Don Klipstein... |
| Posted: Mon Oct 19, 2009 11:01 am |
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In <Xns9CA6E717E25FESntzldfrdSntzldfrdco at (no spam) 216.196.97.142>, Sarah Austin
wrote in part:
[quote]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.
[/quote]
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.
[quote]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.
[/quote]
N:Vision brand "Daylight" at Home Depot is 5500 K with the
usual-for-CFLs CRI of 82.
- Don Klipstein (don at (no spam) misty.com) |
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| Don Klipstein... |
| Posted: Mon Oct 19, 2009 11:07 am |
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In article <hbbe9m$7k5$1 at (no spam) aioe.org>, Rusty wrote:
[quote]"Sarah Austin" <SAustin at (no spam) pndfnospam.com> wrote in message
news:Xns9CA4D3492C7D9SntzldfrdSntzldfrdco at (no spam) 216.196.97.142...
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?
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.
[/quote]
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 (don at (no spam) misty.com) |
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| Don Klipstein... |
| Posted: Mon Oct 19, 2009 11:12 am |
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In <Xns9CA6EB166F841SntzldfrdSntzldfrdco at (no spam) 216.196.97.142>, Sarah Austin
wrote:
[quote]"Rusty" <russjunkmail at (no spam) 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
[/quote]
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 (don at (no spam) misty.com) |
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| Don Klipstein... |
| Posted: Mon Oct 19, 2009 11:53 am |
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In <Xns9CA7C657A5121SntzldfrdSntzldfrdco at (no spam) 216.196.97.142>, Sarah Austin
wrote in part:
[quote]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
[/quote]
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 (don at (no spam) misty.com) |
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| Don Klipstein... |
| Posted: Mon Oct 19, 2009 11:58 am |
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In <Xns9CA8E577EF55SntzldfrdSntzldfrdco at (no spam) 216.196.97.142>, S. Austin wrote:
[quote]"I.N. Galidakis" <morpheus at (no spam) olympus.mons> wrote :
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.
[/quote]
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 (don at (no spam) misty.com) |
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| Don Klipstein... |
| Posted: Mon Oct 19, 2009 12:05 pm |
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In article <1255850890.115840 at (no spam) athprx03>, I.N. Galidakis wrote:
[quote]Sarah Austin wrote:
"I.N. Galidakis" <morpheus at (no spam) olympus.mons> wrote :
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.
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.
[/quote]
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 (don at (no spam) misty.com) |
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| Don Klipstein... |
| Posted: Mon Oct 19, 2009 12:07 pm |
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In <Xns9CA920C75AABSntzldfrdSntzldfrdco at (no spam) 216.196.97.142>, S. Austin wrote:
[quote]"I.N. Galidakis" <morpheus at (no spam) 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:
[/quote]
These come in both 741 and 841, with 841 having better color rendering.
- Don Klipstein (don at (no spam) misty.com) |
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| Don Klipstein... |
| Posted: Mon Oct 19, 2009 12:35 pm |
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In <dould55ncrpd5n7ra1oe3l8t5qk4amfh0g at (no spam) 4ax.com>, V. Roberts wrote in part:
[quote]On Thu, 15 Oct 2009 21:07:01 -0400, "TKM" <noname at (no spam) 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.
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,
[/quote]
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 (don at (no spam) misty.com) |
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| Rusty... |
| Posted: Mon Oct 19, 2009 12:54 pm |
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"I.N. Galidakis" <morpheus at (no spam) olympus.mons> wrote in message
news:1255940237.941913 at (no spam) athprx04...
[quote]
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[/quote]
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.
[quote]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.
[/quote]
Sarah did mention pet birds which should be a factor. |
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| TKM... |
| Posted: Mon Oct 19, 2009 4:43 pm |
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"Don Klipstein" <don at (no spam) manx.misty.com> wrote in message
news:slrnhdplii.dfr.don at (no spam) manx.misty.com...
[quote]In <Xns9CA6EB166F841SntzldfrdSntzldfrdco at (no spam) 216.196.97.142>, Sarah Austin
wrote:
"Rusty" <russjunkmail at (no spam) 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
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 (don at (no spam) misty.com)
[/quote]
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 |
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| Don Klipstein... |
| Posted: Mon Oct 19, 2009 8:03 pm |
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In article <1256015860.388745 at (no spam) athprx03>, I.N. Galidakis wrote:
[quote]Rusty wrote:
"I.N. Galidakis" <morpheus at (no spam) olympus.mons> wrote in message
news:1255940237.941913 at (no spam) 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.
[/quote]
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 (don at (no spam) misty.com) |
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