OT: Wow, compact fluorescent light bulbs already obsolete

[mpm]

On Sunday, January 19, 2020 at 8:35:18 AM UTC-5, Bill Sloman wrote:

Of course the test of colour rendition is the human, which has three different colour sensitive pigments in the cone cells in the retina, and rhodopsin in the rod cells, which is only active at very low light levels.

There's not a lot of point in getting too fussy about the spectral content of your light source, when the detectors in your eyes are sensitive over relatively wide spectral intervals, with a lot of overlap in their ranges.

Then what about CMOS imaging sensors used in digital cameras?
In general, I find photos taken under fluorescent lighting unappealing.
Color balancing (with physical filters, and/or light modifiers for strobes, etc..) can be problematic with fluorescent (and I presume CFL) as the color temperature can be all over the place. Same is true for mercury vapor lights.

Fluorescent lights combined with higher shutter speed can also lead to color cast problems, and light/dark exposure "bands" as the shutter curtain captures the falling intensity cycle of the light source.

Just something to think about.
As a hobbyist photographer, I am not sad that LED's have made CFL's obsolete.
Part of that, no doubt, is laziness on my part, as I'm sure professional photographers could deal with any scene lighting imaginable. Even if they just use lots of expensive artificial lights to overcome the problem.

 

[Sea]

On 01/19/2020 02:25 AM, DecadentLinuxUserNumeroUno@decadence.org wrote:

John Doe <always.look@message.header> wrote in
news:r015hs$6hd$2@dont- email.me:

That history seems strange considering the fact the first consumer
CFLs were inferior technology, resembling early technology LED
flashlights. If the technology had been around so long, they would
have been ready for prime time the day they were first made
available to consumers.


Ya don't need to quote the fuckin' headers. Goddamn boy! how long
you been posting in Usenet, and you are so thick that you cannot
shed retarded bad habits.

A top-posting idiot too, who puts a "dash-dash-space" quote delimiter
right before the introduction to the previous post. Everything from
there down is lost when Thunderbird opens a composition window for
followup to the top-posting idiot.

 

[Michael Terrell]

On Sunday, January 19, 2020 at 11:00:38 AM UTC-5, mpm wrote:

On Sunday, January 19, 2020 at 8:35:18 AM UTC-5, Bill Sloman wrote:

Of course the test of colour rendition is the human, which has three different colour sensitive pigments in the cone cells in the retina, and rhodopsin in the rod cells, which is only active at very low light levels.

There's not a lot of point in getting too fussy about the spectral content of your light source, when the detectors in your eyes are sensitive over relatively wide spectral intervals, with a lot of overlap in their ranges.


Then what about CMOS imaging sensors used in digital cameras?
In general, I find photos taken under fluorescent lighting unappealing.
Color balancing (with physical filters, and/or light modifiers for strobes, etc..) can be problematic with fluorescent (and I presume CFL) as the color temperature can be all over the place. Same is true for mercury vapor lights.

Fluorescent lights combined with higher shutter speed can also lead to color cast problems, and light/dark exposure "bands" as the shutter curtain captures the falling intensity cycle of the light source.

Just something to think about.
As a hobbyist photographer, I am not sad that LED's have made CFL's obsolete.
Part of that, no doubt, is laziness on my part, as I'm sure professional photographers could deal with any scene lighting imaginable. Even if they just use lots of expensive artificial lights to overcome the problem.

It doesn't just affect semiconductor sensors. Florescent lights looked like crap with Vidicon or Plumbicon cameras. Even worse, they caused a lot of flaring on white images. I got into many arguments with idiots who insisted on wearing white shirts to meetings, who bitched that others got closeups, but they didn't. If I did zoom in on them, the flaring would wipe out their smug faces. This happened every month. The worst was a man with a local radio show. I got tired of hearing "Do you know who I am?" I started telling him, "Someone not smart enough to do what they are told. By our franchise, we are required to cover your monthly Township meeting, but I am not required to make you look good, or even have you on camera."

 

[Lasse Langwadt Christense]

søndag den 19. januar 2020 kl. 15.16.22 UTC+1 skrev Martin Brown:

On 18/01/2020 09:01, DecadentLinuxUserNumeroUno@decadence.org wrote:
Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net> wrote in
news:56d2b61b-d473-d2fe-9dc8-d74adb4f2e78@electrooptical.net:

LED street lights could use some diffusers too.

They're hell on astromomers, too.

Amateurs and professionals have learnt a few tricks to help ameliorate
the situation. The switch from HPS and mercury is generally slightly
advantageous to astronomers in that the LED units can be totally off for
part of the night and are generally in full cutoff fixtures with no
light going above the horizontal. Low pressure sodium is still the thing
to beat in terms of efficacy at over 200 lumens/W.

isn't street-lights commonly high pressure sodium?

and afaiu the human is not very sensitive at sodiums main spectral line
in dark conditions, so not all lumens are the same

 

[Bill Sloman]

On Monday, January 20, 2020 at 1:11:01 AM UTC+11, Clifford Heath wrote:

On 20/1/20 12:35 am, Bill Sloman wrote:
On Sunday, January 19, 2020 at 11:43:01 PM UTC+11, Rick C wrote:
On Sunday, January 19, 2020 at 7:18:33 AM UTC-5, upsid...@downunder.com wrote:
On Sat, 18 Jan 2020 15:12:10 -0500, Phil Hobbs
pcdhSpamMeSenseless@electrooptical.net> wrote:

On 2020-01-18 15:05, upsidedown@downunder.com wrote:
On Sat, 18 Jan 2020 14:41:07 -0500, Phil Hobbs
pcdhSpamMeSenseless@electrooptical.net> wrote:


and produce ugly colours.

nonsense. The vast majority were triphosphor in sane CCTs, but it was
possible to find outliers with excessively high CCT, and occasional
junk products with old halophosphate phosphors.

Most CFL tubes use /7xx or /8xx phosphors. Some manufacturers claim
also /9xx models in their catalogs, but I have not seen any CFLs in
real life in the /9xx range. I use some /965 (CRI=9x 6500 K)
"daylight" tubes but they are full size fluorescent tubes.

Okay, what's the exact significance of that?

You must be colour blind.

Let indirect daylight fall on a white surface. Aim the lamp towards
the same surface to a chive similar illumination. With /965 phosphors
is hard to tell the difference and I have often forgot to switch off
the /965 uplighters in the morning when there are sufficient light
outside . Unfortunately /965 CFLs are extremely rare and
unobtainable as LEDs.

It isn't white surfaces that have the problem, it's coloured ones. The
output of CFLs consists of a weak continuum plus several very bright
emission bands.

True for /7xx and /7xx phosphors, not for /9xx phosphors (full size or
CFL if available).

The problem with white LEDs is that it radiates a very strong blue
spectral line from the chip itself and a continuum of red and
yellowish colors from the phosphors. Unfortunately you would have to
select 2700 K or below models to limit the blue emission and hence get
a more balanced total spectrums. With better fluorescent tubes 4000 K
looks quite balanced and even /965 (6500 K) looks good, but 4000 K or
6500 K LEDs would look awful.

CFLs have better colour rendering than white LEDs?

"White" LEDs have a peak in blue and a continuum in yellow/red but the
output around 475 nm is quite low.

Perhaps tricolor RGB LEDs are better in this respect.

Then you get three peaks, still not the same as a white LED. At least with a white LED it can be made with a variety of phosphors so as to provide numerous colors and not just three sharp peaks like the RGB type of LED. It's the many missing wavelengths that provides poor color rendition.

Of course the test of colour rendition is the human, which has three different colour sensitive pigments in the cone cells in the retina, and rhodopsin in the rod cells, which is only active at very low light levels.

There's not a lot of point in getting too fussy about the spectral content of your light source, when the detectors in your eyes are sensitive over relatively wide spectral intervals, with a lot of overlap in their ranges.

They evolved to cope with the continuous gaussian spectral distribution emitted by the sun, but this isn't something we need to copy all that closely.

Eyes might be sensitive over three broad ranges, but reflective
materials do not reflect that way. So while direct RGB LED light can
span the colour gamut, reflected light doesn't appear the same colour as
if it was reflecting white light.

Whoever said that it would? On the other hand there aren't that many narrow-band reflective pigments, so in many cases it is a counsel of perfection.

Fashion photographers do have to be more careful than most about their light sources.

--
Bill Sloman, Sydney

 

[Michael Terrell]

On Sunday, January 19, 2020 at 6:10:21 PM UTC-5, Phil Hobbs wrote:

mpm wrote:
On Sunday, January 19, 2020 at 8:35:18 AM UTC-5, Bill Sloman wrote:

Of course the test of colour rendition is the human, which has three different colour sensitive pigments in the cone cells in the retina, and rhodopsin in the rod cells, which is only active at very low light levels.

There's not a lot of point in getting too fussy about the spectral content of your light source, when the detectors in your eyes are sensitive over relatively wide spectral intervals, with a lot of overlap in their ranges.


Then what about CMOS imaging sensors used in digital cameras?
In general, I find photos taken under fluorescent lighting unappealing.
Color balancing (with physical filters, and/or light modifiers for strobes, etc..) can be problematic with fluorescent (and I presume CFL) as the color temperature can be all over the place. Same is true for mercury vapor lights.

Fluorescent lights combined with higher shutter speed can also lead to color cast problems, and light/dark exposure "bands" as the shutter curtain captures the falling intensity cycle of the light source.

Just something to think about.
As a hobbyist photographer, I am not sad that LED's have made CFL's obsolete.
Part of that, no doubt, is laziness on my part, as I'm sure professional photographers could deal with any scene lighting imaginable. Even if they just use lots of expensive artificial lights to overcome the problem.


Real men use mogul-base 500W, 3400K incandescent photofloods with a
rated life of 25 hours.

Bigot! Some use ones with a four pin Loctal base. Those are only rated for 20 hours.

 

[Phil Hobbs]

mpm wrote:

On Sunday, January 19, 2020 at 8:35:18 AM UTC-5, Bill Sloman wrote:

Of course the test of colour rendition is the human, which has three different colour sensitive pigments in the cone cells in the retina, and rhodopsin in the rod cells, which is only active at very low light levels.

There's not a lot of point in getting too fussy about the spectral content of your light source, when the detectors in your eyes are sensitive over relatively wide spectral intervals, with a lot of overlap in their ranges.


Then what about CMOS imaging sensors used in digital cameras?
In general, I find photos taken under fluorescent lighting unappealing.
Color balancing (with physical filters, and/or light modifiers for strobes, etc..) can be problematic with fluorescent (and I presume CFL) as the color temperature can be all over the place. Same is true for mercury vapor lights.

Fluorescent lights combined with higher shutter speed can also lead to color cast problems, and light/dark exposure "bands" as the shutter curtain captures the falling intensity cycle of the light source.

Just something to think about.
As a hobbyist photographer, I am not sad that LED's have made CFL's obsolete.
Part of that, no doubt, is laziness on my part, as I'm sure professional photographers could deal with any scene lighting imaginable. Even if they just use lots of expensive artificial lights to overcome the problem.

Real men use mogul-base 500W, 3400K incandescent photofloods with a
rated life of 25 hours.

Cheers

Phil Hobbs

 

[Sjouke Burry]

On 19.01.20 10:32, piglet wrote:

On 19/01/2020 2:32 am, Sylvia Else wrote:

The main issue I had with them was their tendency to take longer and
longer to reach maximum brightness as they aged. I think this was more
due to excessive economy in the electrolytic capacitors used in their
manufacture rather than an inherent limitation.

Sylvia.

Sometimes the electrolytic is just fine and the problem is mercury vapor
loss due to combining with electrodes or phosphor poisoning. Gas mixture
and phosphor quality varied a lot between manufacturers.

piglet

All my cfls which stopped working, failed with a bad electrolytic mains
cap,
dried out and failed.
None of them had a bad light tube.
(a simple test was to touch your tv screen with one of the wires of the
tube,
causing light flashes for each sparc from the tv tube.)
Badly designed and cooled electronics, in all of them.
Might be the same for a lot of LED lights too.....................

 

[Phil Hobbs]

upsidedown@downunder.com wrote:

On Sat, 18 Jan 2020 14:46:14 -0500, Phil Hobbs
pcdhSpamMeSenseless@electrooptical.net> wrote:

On 2020-01-18 14:38, upsidedown@downunder.com wrote:
On Sat, 18 Jan 2020 13:19:52 -0500, Phil Hobbs
pcdhSpamMeSenseless@electrooptical.net> wrote:

On 2020-01-18 11:16, Winfield Hill wrote:
Cursitor Doom wrote...

On 18 Jan 2020 07:10:25 -0800, Winfield Hill wrote:

Not so short; History from Wikipedia:

1976: GE engineer, Edward E. Hammer, invents spiral CFL.
1980: Philips model SL, screw-in, integral magnetic ballast.
1985: Osram model EL lamp, including an electronic ballast.
next: development of high-efficacy phosphors...
1995: by Shanghai Xiangshan in China, helical CFLs.
2011: China CFLs were the "dominant technology".
2015: LED prices fell well below US$5 for a basic bulb.
2016: GE, announced phase out of CFL production in the US.
2020: 40 years later, John Doe writes, that was short-lived.

Osram. Now there was a company that knew how to make bulbs.

They still make superior LED light sources. Yesterday I
pushed our 120W green Osram theatre LED to a peak pulse
current of 360 amps, up from its continuous 20 amp rating.
The competing 100W Luminous theatre LEDs failed at 200A.
Also, it's forward voltage increase was modest; I only had
to raise the RIS-796 pulser's voltage up to 30V, from 24V.



I'd be interested in how the lifetime is affected. Overcurrent causes
dislocations to grow, so that the nonradiative recombination becomes
more and more of a problem.

LEDs run at DC are fairly intolerant of overcurrent.

The problem with "white" LEDs is the lifetime of the phosphor.
Stressing it too much and the conversion efficiency drops quite fast.
To achieve usable life times of tens of thousand hours, you need to
run the LED at Imax/2 or even Imax/3.


Not so. The phosphor is mostly inorganic salts, and so is very stable.
See e.g.
https://www.electrochem.org/dl/interface/wtr/wtr09/wtr09_p032-036.pdf> or
https://www.led-professional.com/resources-1/articles/new-glass-based-phosphors-for-white-light-emitting-diodes

You could get some yellowing of the organic binder, of course--that's
mostly what causes optocouplers to degrade at high drive currents.

For some reason, reputable LED manufacturer list the LED
characteristics for currents well below the maximum current. Here is
one example
https://www.cree.com/led-components/media/documents/ds-XD16.pdf

The maximum current is 2000 mA, but except for forward voltage all
other characteristics are given for 350 mA, 700 mA and 1000 mA only.

Probably because it's hard to maintain the specified junction
temperature when you're bombing it that hard.

Unfortunately that data sheet doesn't list the L570 (or L50) lifetimes
is, i.e. how many hours it takes until the light output has dropped to
70 % (resp. 50%) of original value..

However, if some data sheet claims some L50/L70 lifetimes, look
carefully for what junction temperatures and forward currents it is
specified and compare it to the maximum allowed continuous current.

From thermal design point of view, running at maximum current becomes
very hard when trying to keep junction temperatures within limits and
having free air or heatsink temperatures at 25 C .

Running LEDs at Imax/2 or Imax/3, the thermal design is simplified,
higher ambient temperatures are allowed and/or allowing operating at
lower junction temperatures and at dropped radiation levels, extending
the phosphor lifetime.

It should be noted that the phosphors in LEDs are subjected to
radiation densities tens of times larger compared to sunlight and we
all know what exposing some materials to sunlight for a few years will
do to some materials.

Inorganic phosphors are super stable.

Cheers

Phil Hobbs

 

On Sun, 19 Jan 2020 11:56:30 -0800 (PST), Lasse Langwadt Christensen
<langwadt@fonz.dk> wrote:

sřndag den 19. januar 2020 kl. 15.16.22 UTC+1 skrev Martin Brown:
On 18/01/2020 09:01, DecadentLinuxUserNumeroUno@decadence.org wrote:
Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net> wrote in
news:56d2b61b-d473-d2fe-9dc8-d74adb4f2e78@electrooptical.net:

LED street lights could use some diffusers too.

They're hell on astromomers, too.

Amateurs and professionals have learnt a few tricks to help ameliorate
the situation. The switch from HPS and mercury is generally slightly
advantageous to astronomers in that the LED units can be totally off for
part of the night and are generally in full cutoff fixtures with no
light going above the horizontal. Low pressure sodium is still the thing
to beat in terms of efficacy at over 200 lumens/W.


isn't street-lights commonly high pressure sodium?

The production of LPS lamps is being phased out in a year or two.
Astronomers are not happy but everyone else are happy to get rid of
these LPS.

and afaiu the human is not very sensitive at sodiums main spectral line
in dark conditions, so not all lumens are the same

The scotopic viewing affects much lower light levels than used in any
street lighting.

 

[John Doe]

upsidedown@downunder.com wrote:

It should be noted that the phosphors in LEDs are subjected to
radiation densities tens of times larger compared to sunlight and we
all know what exposing some materials to sunlight for a few years will
do to some materials.

Yep. It dries up and cracks (seems that way, I'm not saying that's
exactly what happens) plastics that are not UV resistant.

The base of my CFLs is discolored yellowish-brown. I wonder if that's
heat or if that's UV damage.

 

[John Doe]

Sjouke Burry <burrynulnulfour@ppllaanneett.nnll> wrote:

Badly designed and cooled electronics, in all of them.
Might be the same for a lot of LED lights too...

The sleeve/cuff part of my 75 and 100 W LED light bulbs is too hot to
touch. The LED plastic(?) part of the bulb is just warm. Likely
heatsinking is what the sleeve/cuff part is for. No idea if it's too hot
or how long it will last. Will see!

 

John Doe <always.look@message.header> wrote in
news:r03nec$7cj$3@dont-email.me:

The base of my CFLs is discolored yellowish-brown. I wonder if
that's heat or if that's UV damage.

Answer: Yes.

 

[Martin Brown]

On 19/01/2020 19:56, Lasse Langwadt Christensen wrote:

søndag den 19. januar 2020 kl. 15.16.22 UTC+1 skrev Martin Brown:
On 18/01/2020 09:01, DecadentLinuxUserNumeroUno@decadence.org wrote:
Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net> wrote in
news:56d2b61b-d473-d2fe-9dc8-d74adb4f2e78@electrooptical.net:

LED street lights could use some diffusers too.

They're hell on astromomers, too.

Amateurs and professionals have learnt a few tricks to help ameliorate
the situation. The switch from HPS and mercury is generally slightly
advantageous to astronomers in that the LED units can be totally off for
part of the night and are generally in full cutoff fixtures with no
light going above the horizontal. Low pressure sodium is still the thing
to beat in terms of efficacy at over 200 lumens/W.


isn't street-lights commonly high pressure sodium?

Depends on the country. Historically the UK had a very high proportion
of LPS in major towns and cities for street lighting as did Belgium.

Increasingly city centres were lit by HPS but there is still some
installed base of LPS lamps even now. They are being replaced by LED
fixtures but the councils are being surprised that they do not save any
of the money promised by the "consultants" (aka salesmen). Swapping
200Lm/W for 100Lm/W lighting is never going to save energy.

and afaiu the human is not very sensitive at sodiums main spectral line
in dark conditions, so not all lumens are the same

That isn't correct. The human eye is most sensitive to a mid green 520nm
but it is already very sensitive to yellow. The cones sensitivity is to
Orange, Green and Blue with red being a construction of the brain from
the Orange-Green sensor channel. It means that with a sodium D-line
Didynium filter you get some strange visual effects with out of gamut
colours that look almost cartoon like. Most pronounced in autumn leaves.

--
Regards,
Martin Brown

 

[Lasse Langwadt Christense]

mandag den 20. januar 2020 kl. 10.16.17 UTC+1 skrev Martin Brown:

On 19/01/2020 19:56, Lasse Langwadt Christensen wrote:
søndag den 19. januar 2020 kl. 15.16.22 UTC+1 skrev Martin Brown:
On 18/01/2020 09:01, DecadentLinuxUserNumeroUno@decadence.org wrote:
Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net> wrote in
news:56d2b61b-d473-d2fe-9dc8-d74adb4f2e78@electrooptical.net:

LED street lights could use some diffusers too.

They're hell on astromomers, too.

Amateurs and professionals have learnt a few tricks to help ameliorate
the situation. The switch from HPS and mercury is generally slightly
advantageous to astronomers in that the LED units can be totally off for
part of the night and are generally in full cutoff fixtures with no
light going above the horizontal. Low pressure sodium is still the thing
to beat in terms of efficacy at over 200 lumens/W.


isn't street-lights commonly high pressure sodium?

Depends on the country. Historically the UK had a very high proportion
of LPS in major towns and cities for street lighting as did Belgium.

Increasingly city centres were lit by HPS but there is still some
installed base of LPS lamps even now. They are being replaced by LED
fixtures but the councils are being surprised that they do not save any
of the money promised by the "consultants" (aka salesmen). Swapping
200Lm/W for 100Lm/W lighting is never going to save energy.

and afaiu the human is not very sensitive at sodiums main spectral line
in dark conditions, so not all lumens are the same

That isn't correct. The human eye is most sensitive to a mid green 520nm
but it is already very sensitive to yellow. The cones sensitivity is to
Orange, Green and Blue with red being a construction of the brain from
the Orange-Green sensor channel. It means that with a sodium D-line
Didynium filter you get some strange visual effects with out of gamut
colours that look almost cartoon like. Most pronounced in autumn leaves.

https://upload.wikimedia.org/wikipedia/commons/8/8f/LumEffCIE.jpeg

scotopic seems pretty low at sodiums 589 nm

 

On Saturday, 18 January 2020 23:23:02 UTC, Phil Hobbs wrote:

On 2020-01-18 17:43, tabbypurr wrote:
On Saturday, 18 January 2020 17:30:57 UTC, Phil Hobbs wrote:
On 2020-01-18 06:10, tabbypurr wrote:
On Saturday, 18 January 2020 01:57:45 UTC, Phil Hobbs wrote:
On 2020-01-17 20:46, John Doe wrote:
Phil Hobbs wrote:
John Doe wrote:

I bought CFL lightbulbs once. Now I need some more, I
turn around and they're gone! Replaced by LED light
bulbs. That was a short-lived technology.

Good riddance. CFLs stink on ice.

The poster is uninformed.


They're dim,

not a bit, they're available from 3w to 100s of watts & many
thousand lumens. There was an issue with mfrs claiming wattage
equivalence to nonstandard filament lamps, but that is not due to
any problem with the CFLs obviously.

...just with the ones you could actually buy and use conveniently.
And

I've long been able to buy & use upto a few hundred watts at least.

CFLs of a few hundred watts? Riiiiiigggghhhhttt. Let's see a few links.

https://www.amazon.co.uk/125w-Hydroponics-Grow-Light-Lamp/dp/B009WO1WPC/ref=sr_1_2?keywords=CFL&qid=1579542792&s=outdoors&sr=1-2

https://www.amazon.co.uk/Blue-300w-Hydroponics-Grow-Light/dp/B008A68FKI/ref=sr_1_4?keywords=CFL&qid=1579542792&s=outdoors&sr=1-4

https://www.amazon.co.uk/300w-Grow-Light-lamp-Hydroponics/dp/B009R2U4YY/ref=sr_1_5?keywords=CFL&qid=1579542792&s=outdoors&sr=1-5

https://www.amazon.co.uk/Dual-125w-Hydroponics-Grow-Light/dp/B00CK9LY4A/ref=sr_1_6?keywords=CFL&qid=1579542792&s=outdoors&sr=1-6

https://www.amazon.co.uk/200w-dual-Spectrum-light-Hydroponics/dp/B009R3CPB8/ref=sr_1_8?keywords=CFL&qid=1579542792&s=outdoors&sr=1-8

https://www.amazon.co.uk/Spectrum-Hydroponics-Energy-Flower-Pendant/dp/B00KW640RG/ref=sr_1_11?keywords=CFL&qid=1579542792&s=outdoors&sr=1-11

https://www.amazon.co.uk/Blue-300w-Hanger-Hydroponics-Light/dp/B009W63014/ref=sr_1_12?keywords=CFL&qid=1579542792&s=outdoors&sr=1-12

https://www.amazon.co.uk/200w-Hydroponics-Grow-Light-Lamp/dp/B00OGC9SJ2/ref=sr_1_13?keywords=CFL&qid=1579542792&s=outdoors&sr=1-13

https://www.amazon.co.uk/200w-Blue-Spectrum-Light-Hydroponics/dp/B009R3GBGS/ref=sr_1_14?keywords=CFL&qid=1579542792&s=outdoors&sr=1-14

Those are just off the first page I looked at. Google will get you plenty more on the usual sites. They're still used for growlights & as photographic lighting.

I forget the larget that fit into ceiling pendant fittings, somewhere
around the 60w real watts mark which is way too much light for a
pendant fitting.

I'm talking about table and standard lamps. The gummint banned the
bulbs they were designed for. 100W incandescent (1690 lumens) is about
right for reading by, if it's within 2-3 feet. Good luck getting a
genuine 1690 lumen CFL to fit in a normal table lamp harp, even assuming
you could find such a thing. Most of the '100w equivalent' CFLs claimed
to be around 1100 lumens, and actually came in well below that.

I don't know what you're buying where, I never had any problem getting realistic replacements that fit - and I don't mean so-called 100w equivalent, which as you say come in below spec. (That might have changed now as I no longer buy them.)

Using the ambient light sensor on my phone (a BlackBerry Classic) in an
apples-to-apples geometry, '100W equivalent' CFLs from the supermarket
produced about a third of what they claimed (assuming that the 1690
lumens quoted by GE for their incandescent bulbs wasn't overstated).

then you're buying junk.

they are intrinsically dim--their surface brightness is
dramatically lower than a 100W incandescent's, so very often an
equivalently-bright CFL wouldn't fit the fixture. Lamp harps
especially.

dim no, larger yes

I'm talking about lumens per square metre, not total lumens. Lower
surface brightness -> larger surface for the same output -> larger
physical size for the same luminous output.

So they don't fit. Point made.

of course they're bigger

slow,

There were 2 types of CFL, general purpose & facilities. The
former were not slow.

The facilities ones aren't CFLs, and the domestic ones really are
slow, especially in cold weather. They take seconds to come up to
full brightness, vs. tens of milliseconds for an incandescent or
LED. (The LED is intrinsically a ~100 ns device, but the power
supplies are slower.)

Most CFLs weren't rated for cold service. You could get ones that
were.

Have you got a link for porch light CFLs that work down to 0 F? What
supermarket did you buy them from? Ordinary incandescents work fine
over a huge temperature range.

I think it was megaman that was the main supplier, but I can't be certain. Most supermarkets didn't stock them.

The latter were very slow to warm up, trading that off for better
efficacy, and were never intended for domestic use. I think the
reason facilities lamps occasionally ended up in homes was the
complete failure of mfrs to explain what they were on the pack -
just stating 'facilities' meant nothing to the home buyer.


highly temperature-sensitive,

some were intolerant of small enclosed spaces, most weren't.
Depended on the mercury technology & dose.

It's cold I'm talking about. Those of us who actually save
significant amounts of energy generally do it by turning down the
thermostat, which makes the lights go dim.

you got the wrong ones then

So what exactly would the right ones have been? Any old tungsten or LED
bulb from the corner store works fine there.

Yes, with CFLs one needed to get ones specifically rated for cold service.

and produce ugly colours.

nonsense. The vast majority were triphosphor in sane CCTs, but it
was possible to find outliers with excessively high CCT, and
occasional junk products with old halophosphate phosphors.

You must be colour blind.

no. CFLs used the same phoshors as linear fluorescent, just with
less choice.

As everybody knows, linear fluorescent bulbs also have horrible CRI. If
you don't see that, you must be colour blind as I said.

I'm not colour blind and don't see that. What I observed with linear fl is that there were many with poor CRI, and many that were fine for domestic or work use with CRIs in the 80s & 90s. With CFLs most weren't as bad, some were good, and at the bottom end of course some were pretty awful. But a lot less were bad than linear fl.

Other than that, they rock.

They do save a bit of money, but the amount I spend on
electric light is pretty trivial.

they were a move forward in technology, saving more than they
cost.

And making it hard to read my book, all to save two cents an hour.
No thanks.

You got the wrong ones! Freedom isn't usually a bad thing.

You said it. In a free society I'd be able to buy whatever light bulbs
I like, but I can't any more. Freedom here in the US has been
progressively eroded since 9/11. From the relatively trivial POV of
light bulbs it ended in 2012. (Some fraction or our freedoms remain,
but many irreplaceable ones have been lost.)

Cheers

Phil Hobbs

I agree with you on that. If the things stand on their own merits, people will soon buy them.


NT

 

On Sunday, 19 January 2020 02:45:52 UTC, Rick C wrote:

On Saturday, January 18, 2020 at 8:42:25 PM UTC-5, Phil Hobbs wrote:
On 2020-01-18 20:03, Rick C wrote:
On Saturday, January 18, 2020 at 6:23:02 PM UTC-5, Phil Hobbs wrote:

Have you got a link for porch light CFLs that work down to 0 F?

https://www.1000bulbs.com/product/6781/FC23-801023.html

I'm seeing zero specs for light output at low temperature there. They
say it 'starts' at -20 degrees, but so did the one I used to have on my
porch. It sure didn't make anything like rated output below 50 F,
though--below freezing you couldn't even see to put the key in the lock.
The vapour pressure of mercury is what it is, hype or no hype.

What??? What does the vapor pressure of mercury have to do with it? As long as it is a vapor, it's the same amount mercury no matter what the vapor pressure it.

Vapour pressure has everything to do with it. The reduced output at start is due to most of the mercury not being in vapour phase.


NT

 

On Sunday, 19 January 2020 02:32:18 UTC, Sylvia Else wrote:

The main issue I had with them was their tendency to take longer and
longer to reach maximum brightness as they aged. I think this was more
due to excessive economy in the electrolytic capacitors used in their
manufacture rather than an inherent limitation.

Sylvia.

Electrolytic failure caused 100/120Hz flicker. Slower warmup was due to reduced filament emission & mercury absorption into the phosphors.


NT

 

On Sunday, 19 January 2020 01:43:05 UTC, Phil Hobbs wrote:

On 2020-01-18 19:55, Sylvia Else wrote:
On 18/01/2020 11:57 am, John Doe wrote:

I bought CFL lightbulbs once. Now I need some more, I turn around and
they're gone! Replaced by LED light bulbs. That was a short-lived
technology.


They've been around for a lot longer than most people realise. It's just
that they didn't become popular until governments started banning
incandescent lamps.

Because they suck.

Cheers

Phil Hobbs

aiui they didn't become popular primarily because of the cost. And IIRC they became popular before incandescents were banned, making some people that could no longer see in FL incandescent with anger.


NT

 

On Sunday, 19 January 2020 01:42:25 UTC, Phil Hobbs wrote:

On 2020-01-18 20:03, Rick C wrote:
On Saturday, January 18, 2020 at 6:23:02 PM UTC-5, Phil Hobbs wrote:
On 2020-01-18 17:43, tabbypurr wrote:
On Saturday, 18 January 2020 17:30:57 UTC, Phil Hobbs wrote:
On 2020-01-18 06:10, tabbypurr wrote:
On Saturday, 18 January 2020 01:57:45 UTC, Phil Hobbs wrote:
On 2020-01-17 20:46, John Doe wrote:
Phil Hobbs wrote:
John Doe wrote:

I've long been able to buy & use upto a few hundred watts at
least.

CFLs of a few hundred watts? Riiiiiigggghhhhttt. Let's see a few
links.

So do you do your work without researching??? This is just one link
of many. Google is your friend. I searched on 400 watt CFL but the
web site search showed lamps all the way up to this 600 watt bulb.

https://www.1000bulbs.com/product/7671/FC200-FEIIIB277.html

We're talking about domestic bulbs, here. That's a mogul-base bulb--I
have zero mogul-base fixtures in my house--do you have any? The last
one I used was in about 1978 in a photo shoot.

I thought we were talking about CFLs rated 100s of watts. I was anyway. No-one is likely to put those into standard domestic luminaires.

A 100-W tungsten lamp was about 75 cents, iirc. Have you ever measured
any of those "100W-equivalent" bulbs? I have. They all sucked.

I assume you used an integrating sphere & waited for them to warm up fully. I encountered very few that bad.

Using the ambient light sensor on my phone (a BlackBerry Classic)
in an apples-to-apples geometry, '100W equivalent' CFLs from the
supermarket produced about a third of what they claimed (assuming
that the 1690 lumens quoted by GE for their incandescent bulbs
wasn't overstated).

I don't know quite what you mean by apples to apples geometry, I'm aware that the light output pattern was typically different to filament lamps.

What lamps are you using that you can't fit a 1600 lumen CFL into
it? They may be a bit taller so the harp won't fit as well. I bought
a couple of table lamps made in China and they had cut the harp wire
so short it would bump the top of the CFL I was fitting into it.
They fit all the older lamps just fine.

Lots.

it was a common issue. Changes in lightbulb technology usually do result in some light fittings needing to be changed or using not the ideal bulb. But FWIW most people did not try to put 100w equivalents into small tablelamps..

Most CFLs weren't rated for cold service. You could get ones that
were.

Have you got a link for porch light CFLs that work down to 0 F?

https://www.1000bulbs.com/product/6781/FC23-801023.html

I'm seeing zero specs for light output at low temperature there. They
say it 'starts' at -20 degrees, but so did the one I used to have on my
porch. It sure didn't make anything like rated output below 50 F,
though--below freezing you couldn't even see to put the key in the lock.
The vapour pressure of mercury is what it is, hype or no hype.

Some were rated to give full output in cold conditions. All CFLs had to warm up, how quickly depended on how the ballast handled a cool tube and how the tube dealt with its mercury content. You can't change the physics of mercury but lamp makers did change the quantities put in the lamps, and use amalgam versus just mercury. Other gas content could also be changed - I know less about that.

What supermarket did you buy them from? Ordinary incandescents
work fine over a huge temperature range.

No, they only work at thousands of degrees, but the are self heating
so it works out.

Thousands of degrees? The housing is made of plastic, dude.

glass, metals, putty. They tolerated 250C albeit with some putty failures.

It's cold I'm talking about. Those of us who actually save
significant amounts of energy generally do it by turning down
the thermostat, which makes the lights go dim.

you got the wrong ones then

So what exactly would the right ones have been? Any old tungsten
or LED bulb from the corner store works fine there.

Maybe you need to actually read in info. Just like many things CFLs
can be made very cheaply and won't work well. Or they can work
great if you buy good ones.

BITD you could get good bulbs at the supermarket. With newer LED bulbs,
that happy state may be returning. Not in the CFL period, however.

whose fault was that? Either supermarkets or end users or mfrs for not making the issue clearer on the box, or more likely some of all 3.


NT