When dimming tungsten lamps, it was pretty well known the efficiency
dropped dramatically. In other words, you got less lumens (or whatever)
per watt consumed. Does the same apply to LEDs? Or just to a lesser extent?

--
*Time is fun when you're having flies... Kermit

Dave Plowman London SW
To e-mail, change noise into sound.

On 16/01/2019 13:54, Dave Plowman (News) wrote:
When dimming tungsten lamps, it was pretty well known the efficiency
dropped dramatically. In other words, you got less lumens (or whatever)
per watt consumed. Does the same apply to LEDs? Or just to a lesser extent?


Dimmed using PWM or by varying the current?

LEDs are usually far more efficient than tungsten especially when dimmed
but it does depend on the power supply design.

You probably get near the same efficiency from a PWM controlled LED as
from one that is run at full current.

On Wednesday, 16 January 2019 14:02:59 UTC, Dave Plowman (News) wrote:

When dimming tungsten lamps, it was pretty well known the efficiency
dropped dramatically. In other words, you got less lumens (or whatever)
per watt consumed. Does the same apply to LEDs? Or just to a lesser extent?

no, LED efficacy improves a bit when dimmed as V_f drops a little.


NT

A lot of these super bright leds seem to use pulse driven leds over running
them in bursts to achieve the bright effect. I do not know how much this
treatment shortens their lives, but according to some people on the web it
has to be this way due to the poor thermal conduction of the led substrate.
Not having ever seen a substrate I cannot possibly comment!
Brian

--
----- --
This newsgroup posting comes to you directly from...
The Sofa of Brian Gaff...

Blind user, so no pictures please
Note this Signature is meaningless.!
"dennis@home" wrote in message
...
On 16/01/2019 13:54, Dave Plowman (News) wrote:
When dimming tungsten lamps, it was pretty well known the efficiency
dropped dramatically. In other words, you got less lumens (or whatever)
per watt consumed. Does the same apply to LEDs? Or just to a lesser
extent?


Dimmed using PWM or by varying the current?

LEDs are usually far more efficient than tungsten especially when dimmed
but it does depend on the power supply design.

You probably get near the same efficiency from a PWM controlled LED as
from one that is run at full current.

On 16/01/2019 16:14, wrote:
On Wednesday, 16 January 2019 14:02:59 UTC, Dave Plowman (News) wrote:

When dimming tungsten lamps, it was pretty well known the efficiency
dropped dramatically. In other words, you got less lumens (or whatever)
per watt consumed. Does the same apply to LEDs? Or just to a lesser extent?

no, LED efficacy improves a bit when dimmed as V_f drops a little.


Normally only true from the 80 to 100 % dimming range.



--
Adam

replying to Dave Plowman (News), tahrey wrote:
The method by which they produce light is very much different from how
tungsten filaments do, direct photon emission rather than having to make a
piece of wire so hot it begins to glow, so I'd be surprised if their output
light vs input power varies much from completely linear. Possibly they get a
bit less efficient as you turn the brightness *up* (as the greater dissipated
power, and greater current, makes for more heat that has to be sunk, which
then doubles down by making the semiconductors less efficient), and the
LED+Driver system as a whole may lose efficiency at low brightness depending
on how the dimming is achieved (PWM switching, or simple inline resistance)
and losses in switchmode transformers at marginal power draws (which is sort
of analogous to the losses in a traditional dimmer switch itself, rather than
the bulb).

The thing with the tungsten lamps is once you start reducing voltage below
what they're rated for mainline use at, you're reducing their effective
temperature and shifting their emitted spectrum further down the waveband; in
other words, the ratio of light vs heat emitted switches more towards the heat
end, and only avoids melting the filament because the total emitted power is
so much less, thus less heat has to be dissipated even though it makes up a
greater proportion of the total (similarly attempts to improve the efficiency
and raise the colour temperature by increasing the voltage can only be taken a
little way before the bulb fails, because although the proportion of power
dissipated as heat is proportionally less, it's still materially more and ends
up melting the filament).

So if you derate a 60w (consumption) incandescent bulb to 20w using a dimmer,
it may go from producing 50w of heat and 10w of light (5:1, 16.7% efficient),
to 17.5w of heat and 2.5w of light (7:1, 12.5% efficient; naturally these are
not real world figures and just pulled out of the air). Your 12w LED
replacement starts out emitting 2w of heat and 10w of light, derating to 4w in
kind (ie 1/3rd) should see it emitting 0.67w of heat and 3.33w of light, and
to emit the same brightness as the dimmed incandescent you'll instead want to
derate to 3w (not counting transformer/etc losses), for 0.5w heat and 2.5w
light.

The other clue is that the quality of light changes with incandescents when
you dim them, the colour shifts towards the red-orange end of the spectrum
(and beyond that, deeper into the infrared). The colour of a dimmed LED
remains constant, with no wavelength shifts; it just reduces in quantity. So
no additional heat should be produced, in fact due to the reducing current it
should reduce in proportion to the useful output (ie visible light), and the
losses will be traceable more to the power supply.

There are efficient ways to convert mains power to something LEDs can use, and
cheap and easy/compact ways to do it, and there's not the greatest amount of
overlap between them, so they should always be measured at the point of mains
supply rather than at output to the diodes, but on the whole even the iffiest
dimmable LED should remain more efficient than an equivalent incandescent...
else you'll find an incandescent-like amount of heat being emitted from the
electronics.

--
for full context, visit https://www.homeownershub.com/uk-diy...s-1340334-.htm

In article ,
tahrey m wrote:
The other clue is that the quality of light changes with incandescents
when you dim them, the colour shifts towards the red-orange end of the
spectrum (and beyond that, deeper into the infrared). The colour of a
dimmed LED remains constant, with no wavelength shifts; it just reduces
in quantity. So no additional heat should be produced, in fact due to
the reducing current it should reduce in proportion to the useful output
(ie visible light

Which is one thing I dislike about LEDs. I tend to dim lights when I'm
relaxing. And the 'sun going down' quality of the light from dimmed
tungsten suits me well. And that's before LEDs not matching halogen
quality when that's on full. Perhaps one day.

--
*Beauty is in the eye of the beer holder...

Dave Plowman London SW
To e-mail, change noise into sound.

On Wednesday, 23 January 2019 14:22:51 UTC, Dave Plowman (News) wrote:
In article ,
tahrey m wrote:
The other clue is that the quality of light changes with incandescents
when you dim them, the colour shifts towards the red-orange end of the
spectrum (and beyond that, deeper into the infrared). The colour of a
dimmed LED remains constant, with no wavelength shifts; it just reduces
in quantity. So no additional heat should be produced, in fact due to
the reducing current it should reduce in proportion to the useful output
(ie visible light

Which is one thing I dislike about LEDs. I tend to dim lights when I'm
relaxing. And the 'sun going down' quality of the light from dimmed
tungsten suits me well. And that's before LEDs not matching halogen
quality when that's on full. Perhaps one day.

I've been saying similar for years, but the hue bulbs could be the answer but they arent very bright compared to anything else.

In article ,
whisky-dave wrote:
On Wednesday, 23 January 2019 14:22:51 UTC, Dave Plowman (News) wrote:
In article ,
tahrey m wrote:
The other clue is that the quality of light changes with
incandescents when you dim them, the colour shifts towards the
red-orange end of the spectrum (and beyond that, deeper into the
infrared). The colour of a dimmed LED remains constant, with no
wavelength shifts; it just reduces in quantity. So no additional
heat should be produced, in fact due to the reducing current it
should reduce in proportion to the useful output (ie visible light

Which is one thing I dislike about LEDs. I tend to dim lights when I'm
relaxing. And the 'sun going down' quality of the light from dimmed
tungsten suits me well. And that's before LEDs not matching halogen
quality when that's on full. Perhaps one day.

I've been saying similar for years, but the hue bulbs could be the
answer but they arent very bright compared to anything else.

That could be the problem. The more you fiddle with LEDs to get a
continuous spectrum, the more the efficiency drops. Same, really, as with
florries - but more so.

--
*Remember not to forget that which you do not need to know.*

Dave Plowman London SW
To e-mail, change noise into sound.

I messed around with light transmitters when i was younger. a filament bulb
could only have a very low amount of modulation added to it due to thermal
lag. If you attempted to drive it anywhere near where you could see it
flicker it sounded like a transistor radio with sand in the speaker.
However early high brightness LEDs did not seem to have this problem at
all. Obviously if you went to the almost off point it was clipped and you
needed to watch overdriving for obvious reasons but none of that non linear
effect otherwise.


Brian

--
----- --
This newsgroup posting comes to you directly from...
The Sofa of Brian Gaff...

Blind user, so no pictures please
Note this Signature is meaningless.!
"tahrey" m wrote in
message ...
replying to Dave Plowman (News), tahrey wrote:
The method by which they produce light is very much different from how
tungsten filaments do, direct photon emission rather than having to make a
piece of wire so hot it begins to glow, so I'd be surprised if their
output
light vs input power varies much from completely linear. Possibly they get
a
bit less efficient as you turn the brightness *up* (as the greater
dissipated
power, and greater current, makes for more heat that has to be sunk, which
then doubles down by making the semiconductors less efficient), and the
LED+Driver system as a whole may lose efficiency at low brightness
depending
on how the dimming is achieved (PWM switching, or simple inline
resistance)
and losses in switchmode transformers at marginal power draws (which is
sort
of analogous to the losses in a traditional dimmer switch itself, rather
than
the bulb).

The thing with the tungsten lamps is once you start reducing voltage below
what they're rated for mainline use at, you're reducing their effective
temperature and shifting their emitted spectrum further down the waveband;
in
other words, the ratio of light vs heat emitted switches more towards the
heat
end, and only avoids melting the filament because the total emitted power
is
so much less, thus less heat has to be dissipated even though it makes up
a
greater proportion of the total (similarly attempts to improve the
efficiency
and raise the colour temperature by increasing the voltage can only be
taken a
little way before the bulb fails, because although the proportion of power
dissipated as heat is proportionally less, it's still materially more and
ends
up melting the filament).

So if you derate a 60w (consumption) incandescent bulb to 20w using a
dimmer,
it may go from producing 50w of heat and 10w of light (5:1, 16.7%
efficient),
to 17.5w of heat and 2.5w of light (7:1, 12.5% efficient; naturally these
are
not real world figures and just pulled out of the air). Your 12w LED
replacement starts out emitting 2w of heat and 10w of light, derating to
4w in
kind (ie 1/3rd) should see it emitting 0.67w of heat and 3.33w of light,
and
to emit the same brightness as the dimmed incandescent you'll instead want
to
derate to 3w (not counting transformer/etc losses), for 0.5w heat and 2.5w
light.

The other clue is that the quality of light changes with incandescents
when
you dim them, the colour shifts towards the red-orange end of the spectrum
(and beyond that, deeper into the infrared). The colour of a dimmed LED
remains constant, with no wavelength shifts; it just reduces in quantity.
So
no additional heat should be produced, in fact due to the reducing current
it
should reduce in proportion to the useful output (ie visible light), and
the
losses will be traceable more to the power supply.

There are efficient ways to convert mains power to something LEDs can use,
and
cheap and easy/compact ways to do it, and there's not the greatest amount
of
overlap between them, so they should always be measured at the point of
mains
supply rather than at output to the diodes, but on the whole even the
iffiest
dimmable LED should remain more efficient than an equivalent
incandescent...
else you'll find an incandescent-like amount of heat being emitted from
the
electronics.

--
for full context, visit
https://www.homeownershub.com/uk-diy...s-1340334-.htm

When the blue leds came out merely by changing feedback in the drivers you
could get the mixed light to dim a bit like a tungsten but I'd have thought
all of that could be easily done nowadays in the actual driver chips.

After all I still imagine white is more than on Led in the same housing.
I wonder if you could use a laser diode as a light transmitter?
Brian

--
----- --
This newsgroup posting comes to you directly from...
The Sofa of Brian Gaff...

Blind user, so no pictures please
Note this Signature is meaningless.!
"whisky-dave" wrote in message
...
On Wednesday, 23 January 2019 14:22:51 UTC, Dave Plowman (News) wrote:
In article ,
tahrey m wrote:
The other clue is that the quality of light changes with incandescents
when you dim them, the colour shifts towards the red-orange end of the
spectrum (and beyond that, deeper into the infrared). The colour of a
dimmed LED remains constant, with no wavelength shifts; it just reduces
in quantity. So no additional heat should be produced, in fact due to
the reducing current it should reduce in proportion to the useful
output
(ie visible light

Which is one thing I dislike about LEDs. I tend to dim lights when I'm
relaxing. And the 'sun going down' quality of the light from dimmed
tungsten suits me well. And that's before LEDs not matching halogen
quality when that's on full. Perhaps one day.

I've been saying similar for years, but the hue bulbs could be the answer
but they arent very bright compared to anything else.

On Wednesday, 23 January 2019 16:49:24 UTC, Brian Gaff wrote:
When the blue leds came out merely by changing feedback in the drivers.
I don;t think that is true, blue LEDs needed a different 'chemical' in order to produce blue light nothing to do with driver feedback.

you
could get the mixed light to dim a bit like a tungsten but I'd have thought
all of that could be easily done nowadays in the actual driver chips.

No, nothong to do with the driver.


After all I still imagine white is more than on Led in the same housing.

Some use a specific LED for white light.

I wonder if you could use a laser diode as a light transmitter?
Brian

Well lasers do produce light not sure what yuo mean by transmitter though.

"Dave Plowman (News)" wrote in message
...
In article ,
tahrey m wrote:
The other clue is that the quality of light changes with incandescents
when you dim them, the colour shifts towards the red-orange end of the
spectrum (and beyond that, deeper into the infrared). The colour of a
dimmed LED remains constant, with no wavelength shifts; it just reduces
in quantity. So no additional heat should be produced, in fact due to
the reducing current it should reduce in proportion to the useful output
(ie visible light

Which is one thing I dislike about LEDs. I tend to dim lights when I'm
relaxing. And the 'sun going down' quality of the light from dimmed
tungsten suits me well. And that's before LEDs not matching halogen
quality when that's on full. Perhaps one day.

Its here now with the best of the LEDs which have full color temperature
and dimming control and you are free to specify a set of color temps
and brightness and switch between them.

On Wednesday, 23 January 2019 16:32:07 UTC, Dave Plowman (News) wrote:

That could be the problem. The more you fiddle with LEDs to get a
continuous spectrum, the more the efficiency drops.

who is trying to get continuous spectrum from LED lighting?


Same, really, as with
florries - but more so.

Halophosphates gave far closer to full spectrum than the more modern & far more efficient triphosphor coatings.


NT

On Wednesday, January 23, 2019 at 2:22:51 PM UTC, Dave Plowman (News) wrote:
In article ,
tahrey m wrote:
The other clue is that the quality of light changes with incandescents
when you dim them, the colour shifts towards the red-orange end of the
spectrum (and beyond that, deeper into the infrared). The colour of a
dimmed LED remains constant, with no wavelength shifts; it just reduces
in quantity. So no additional heat should be produced, in fact due to
the reducing current it should reduce in proportion to the useful output
(ie visible light

Which is one thing I dislike about LEDs. I tend to dim lights when I'm
relaxing. And the 'sun going down' quality of the light from dimmed
tungsten suits me well. And that's before LEDs not matching halogen
quality when that's on full. Perhaps one day.

--
*Beauty is in the eye of the beer holder...

Dave Plowman London SW
To e-mail, change noise into sound.

Philips Warm Glow lamps dim spectacularly nicely even on standard dimmers and do shift red a bit.

https://www.toolstation.com/philips-...pe-lamp/p36416

In article ,
Steven wrote:
Which is one thing I dislike about LEDs. I tend to dim lights when I'm
relaxing. And the 'sun going down' quality of the light from dimmed
tungsten suits me well. And that's before LEDs not matching halogen
quality when that's on full. Perhaps one day.

Its here now with the best of the LEDs which have full color temperature
and dimming control and you are free to specify a set of color temps
and brightness and switch between them.

Sadly, there's more to light quality than the nominal colour temperture.

Dips in the spectrum effect some colours but not others. Etc.

--
*I believe five out of four people have trouble with fractions. *

Dave Plowman London SW
To e-mail, change noise into sound.

In article ,
wrote:
On Wednesday, 23 January 2019 16:32:07 UTC, Dave Plowman (News) wrote:

That could be the problem. The more you fiddle with LEDs to get a
continuous spectrum, the more the efficiency drops.

who is trying to get continuous spectrum from LED lighting?

If you want colours to look fairly similar as in daylight, me.


Same, really, as with
florries - but more so.

Halophosphates gave far closer to full spectrum than the more modern &
far more efficient triphosphor coatings.

True. But I reckon a decent triphosphor is closer than any LED I've come
across.

--
*One nice thing about egotists: they don't talk about other people.

Dave Plowman London SW
To e-mail, change noise into sound.

"Dave Plowman (News)" wrote in message
...
In article ,
Steven wrote:
Which is one thing I dislike about LEDs. I tend to dim lights when I'm
relaxing. And the 'sun going down' quality of the light from dimmed
tungsten suits me well. And that's before LEDs not matching halogen
quality when that's on full. Perhaps one day.

Its here now with the best of the LEDs which have full color temperature
and dimming control and you are free to specify a set of color temps
and brightness and switch between them.

Sadly, there's more to light quality than the nominal colour temperture.

Yes, but those more expensive leds go out of their way to
do a lot more than just vary the nominal colour temperature.

Dips in the spectrum effect some colours but not others. Etc.

Those don’t have dips in the spectrum for that reason.

On Thursday, 24 January 2019 18:42:34 UTC, Dave Plowman (News) wrote:
In article ,
tabbypurr wrote:
On Wednesday, 23 January 2019 16:32:07 UTC, Dave Plowman (News) wrote:

That could be the problem. The more you fiddle with LEDs to get a
continuous spectrum, the more the efficiency drops.

who is trying to get continuous spectrum from LED lighting?

If you want colours to look fairly similar as in daylight, me.

so no-one commercially. For a long time researchers were trying to develop phosphors that only produced the peak light frequencies to improve efficacy.


Same, really, as with
florries - but more so.

Halophosphates gave far closer to full spectrum than the more modern &
far more efficient triphosphor coatings.

True. But I reckon a decent triphosphor is closer than any LED I've come
across.

90s CRI versus 80s. Moving away from continuous spectrum is more the focus of commercial research as it improves efficacy.


NT

On Thursday, 24 January 2019 19:43:29 UTC, Steven wrote:
"Dave Plowman (News)" wrote in message
...
In article ,
Steven wrote:

Which is one thing I dislike about LEDs. I tend to dim lights when I'm
relaxing. And the 'sun going down' quality of the light from dimmed
tungsten suits me well. And that's before LEDs not matching halogen
quality when that's on full. Perhaps one day.

Its here now with the best of the LEDs which have full color temperature
and dimming control and you are free to specify a set of color temps
and brightness and switch between them.

Sadly, there's more to light quality than the nominal colour temperture..

Yes, but those more expensive leds go out of their way to
do a lot more than just vary the nominal colour temperature.

Dips in the spectrum effect some colours but not others. Etc.

Those dont have dips in the spectrum for that reason.

cobblers. Is this Rod again?

On Fri, 25 Jan 2019 06:43:18 +1100, Steven, better known as cantankerous
trolling senile geezer Rot Speed, wrote:


Dips in the spectrum effect some colours but not others. Etc.

Those don¢t have dips in the spectrum for that reason.

Let me guess, senile Rot: you suppose you are in Blowman's killfile, so
nym-shifted, yet AGAIN! You are one disgusting senile cretin indeed! tsk

--
Bod addressing abnormal senile quarreller Rot:
"Do you practice arguing with yourself in an empty room?"
MID:

On Thursday, 24 January 2019 18:42:34 UTC, Dave Plowman (News) wrote:
In article ,
Steven wrote:
Which is one thing I dislike about LEDs. I tend to dim lights when I'm
relaxing. And the 'sun going down' quality of the light from dimmed
tungsten suits me well. And that's before LEDs not matching halogen
quality when that's on full. Perhaps one day.

Its here now with the best of the LEDs which have full color temperature
and dimming control and you are free to specify a set of color temps
and brightness and switch between them.

Sadly, there's more to light quality than the nominal colour temperture.

Dips in the spectrum effect some colours but not others. Etc.

Yes as daylight comes from the sun who's light mainly comes from hydrogen it's NOT the same as any LED presently produced on earth.

On 25/01/2019 12:11, whisky-dave wrote:
On Thursday, 24 January 2019 18:42:34 UTC, Dave Plowman (News) wrote:
In article ,
Steven wrote:
Which is one thing I dislike about LEDs. I tend to dim lights when I'm
relaxing. And the 'sun going down' quality of the light from dimmed
tungsten suits me well. And that's before LEDs not matching halogen
quality when that's on full. Perhaps one day.

Its here now with the best of the LEDs which have full color temperature
and dimming control and you are free to specify a set of color temps
and brightness and switch between them.

Sadly, there's more to light quality than the nominal colour temperture.

Dips in the spectrum effect some colours but not others. Etc.

Yes as daylight comes from the sun who's light mainly comes from hydrogen it's NOT the same as any LED presently produced on earth.

I doubt much of the light from the Sun is attributable to the hydrogen.
It's mostly 6000K black body radiation.

--
Max Demian

On 25/01/2019 12:11, whisky-dave wrote:
On Thursday, 24 January 2019 18:42:34 UTC, Dave Plowman (News)
wrote:
In article , Steven
wrote:
Which is one thing I dislike about LEDs. I tend to dim lights
when I'm relaxing. And the 'sun going down' quality of the
light from dimmed tungsten suits me well. And that's before
LEDs not matching halogen quality when that's on full. Perhaps
one day.

Its here now with the best of the LEDs which have full color
temperature and dimming control and you are free to specify a set
of color temps and brightness and switch between them.

Sadly, there's more to light quality than the nominal colour
temperture.

Dips in the spectrum effect some colours but not others. Etc.

Yes as daylight comes from the sun who's light mainly comes from
hydrogen it's NOT the same as any LED presently produced on earth.





The brightest peaks are from sodium.
Sunlight is not a continuous spectrum even though it looks like it.

On Sat, 26 Jan 2019 20:09:56 +0000, "dennis@home"
wrote:

On 25/01/2019 12:11, whisky-dave wrote:
On Thursday, 24 January 2019 18:42:34 UTC, Dave Plowman (News)
wrote:
In article , Steven
wrote:
Which is one thing I dislike about LEDs. I tend to dim lights
when I'm relaxing. And the 'sun going down' quality of the
light from dimmed tungsten suits me well. And that's before
LEDs not matching halogen quality when that's on full. Perhaps
one day.

Its here now with the best of the LEDs which have full color
temperature and dimming control and you are free to specify a set
of color temps and brightness and switch between them.

Sadly, there's more to light quality than the nominal colour
temperture.

Dips in the spectrum effect some colours but not others. Etc.

Yes as daylight comes from the sun who's light mainly comes from
hydrogen it's NOT the same as any LED presently produced on earth.





The brightest peaks are from sodium.

Sodium makes its presence known by absorption lines, not peaks.

Sunlight is not a continuous spectrum even though it looks like it.

Actually it is, more or less. It corresponds to black body radiation
from an object at ~6000K (the surface temperature of the sun) with
numerous absorption lines due to the presence of various elements in
the solar atmosphere.

On Friday, 25 January 2019 17:57:55 UTC, Max Demian wrote:
On 25/01/2019 12:11, whisky-dave wrote:
On Thursday, 24 January 2019 18:42:34 UTC, Dave Plowman (News) wrote:
In article ,
Steven wrote:
Which is one thing I dislike about LEDs. I tend to dim lights when I'm
relaxing. And the 'sun going down' quality of the light from dimmed
tungsten suits me well. And that's before LEDs not matching halogen
quality when that's on full. Perhaps one day.

Its here now with the best of the LEDs which have full color temperature
and dimming control and you are free to specify a set of color temps
and brightness and switch between them.

Sadly, there's more to light quality than the nominal colour temperture.

Dips in the spectrum effect some colours but not others. Etc.

Yes as daylight comes from the sun who's light mainly comes from hydrogen it's NOT the same as any LED presently produced on earth.

I doubt much of the light from the Sun is attributable to the hydrogen.

Then how do yuo think the sun produces light ? ...

The Sun produces light by a nuclear reaction called fusion. As atoms of hydrogen combine to form helium, they produce vast amounts of heat and light.

It is NOT from rechargable batteries !

It's mostly 6000K black body radiation.

and where does that come from ?

Used batteries ?



--
Max Demian

On 28/01/2019 12:15, whisky-dave wrote:
On Friday, 25 January 2019 17:57:55 UTC, Max Demian wrote:
On 25/01/2019 12:11, whisky-dave wrote:
On Thursday, 24 January 2019 18:42:34 UTC, Dave Plowman (News) wrote:
In article ,
Steven wrote:
Which is one thing I dislike about LEDs. I tend to dim lights when I'm
relaxing. And the 'sun going down' quality of the light from dimmed
tungsten suits me well. And that's before LEDs not matching halogen
quality when that's on full. Perhaps one day.

Its here now with the best of the LEDs which have full color temperature
and dimming control and you are free to specify a set of color temps
and brightness and switch between them.

Sadly, there's more to light quality than the nominal colour temperture.

Dips in the spectrum effect some colours but not others. Etc.

Yes as daylight comes from the sun who's light mainly comes from hydrogen it's NOT the same as any LED presently produced on earth.

I doubt much of the light from the Sun is attributable to the hydrogen.

Then how do yuo think the sun produces light ? ...

The Sun produces light by a nuclear reaction called fusion. As atoms of hydrogen combine to form helium, they produce vast amounts of heat and light.

It is NOT from rechargable batteries !

It's mostly 6000K black body radiation.

and where does that come from ?

Used batteries ?

You implied that the fact that the Sun's light "comes from hydrogen"
would affect the quality of light, as if we are looking at spectral
lines, like the yellow of sodium lights. The hydrogen to helium nuclear
reaction just produces heat and it's largely the temperature (6000K)
that determines the quality of light, not the fact that hydrogen is
involved.

--
Max Demian