The open areas of our works are floodlit. Originally incandescent, then
tungsten and now metal halide.
We use 150w, 250w & 400w mh lamps. All on 9m stands and operated by
dusk/dawn sensors. Some of these lamps are now again degraded.
I am thinking that these metal halides would 'roughly' equate to 500, 750
and 1000w tungsten lamps.
Thinking of converting to led. Not for greenery but for (1) reduced running
cost and (2) ease of replacement as I'm the one one that maintains them.
Never have had much fondness of heights.
I haven't a clue as to what size led replacements I might be looking for and
would appreciate help on this.

The 400watters could be replaced by 2x 200/250w (MH-led) equivalents. This
might prove a bonus in terms of better coverage.

Any thoughts please on led output comparisons and perhaps suppliers of
suitable luminaires?
Thanks,
Nick.

In article , Nick
wrote:
The open areas of our works are floodlit. Originally incandescent, then
tungsten and now metal halide. We use 150w, 250w & 400w mh lamps. All on
9m stands and operated by dusk/dawn sensors. Some of these lamps are now
again degraded. I am thinking that these metal halides would 'roughly'
equate to 500, 750 and 1000w tungsten lamps. Thinking of converting to
led. Not for greenery but for (1) reduced running cost and (2) ease of
replacement as I'm the one one that maintains them. Never have had much
fondness of heights. I haven't a clue as to what size led replacements I
might be looking for and would appreciate help on this.

The 400watters could be replaced by 2x 200/250w (MH-led) equivalents.
This might prove a bonus in terms of better coverage.

Any thoughts please on led output comparisons and perhaps suppliers of
suitable luminaires? Thanks, Nick.

tlc ( www.tlc-direct.co.uk ) now stock a wide range but they all seem to
have pir sensors.

--
From KT24

Using a RISC OS computer running v5.18

On Thursday, November 27, 2014 7:27:09 PM UTC, Nick wrote:
The open areas of our works are floodlit. Originally incandescent, then
tungsten and now metal halide.
We use 150w, 250w & 400w mh lamps. All on 9m stands and operated by
dusk/dawn sensors. Some of these lamps are now again degraded.
I am thinking that these metal halides would 'roughly' equate to 500, 750
and 1000w tungsten lamps.
Thinking of converting to led. Not for greenery but for (1) reduced running
cost and (2) ease of replacement as I'm the one one that maintains them.
Never have had much fondness of heights.
I haven't a clue as to what size led replacements I might be looking for and
would appreciate help on this.

The 400watters could be replaced by 2x 200/250w (MH-led) equivalents. This
might prove a bonus in terms of better coverage.

Any thoughts please on led output comparisons and perhaps suppliers of
suitable luminaires?
Thanks,
Nick.

http://wiki.diyfaq.org.uk/index.php?title=Lighting
You'd need to read several articles in that category to answer the q. Light output is covered by lumens, CCT and CRI, the latter explained in the fluorescent article.


NT

In article ,
"Nick" writes:
The open areas of our works are floodlit. Originally incandescent, then
tungsten and now metal halide.
We use 150w, 250w & 400w mh lamps. All on 9m stands and operated by
dusk/dawn sensors. Some of these lamps are now again degraded.
I am thinking that these metal halides would 'roughly' equate to 500, 750
and 1000w tungsten lamps.

That's probably not far off (although when you get to 1000W mains
filament lamps, they are significantly more efficient than 100W
and lower lamps).

Thinking of converting to led. Not for greenery but for (1) reduced running
cost and (2) ease of replacement as I'm the one one that maintains them.
Never have had much fondness of heights.
I haven't a clue as to what size led replacements I might be looking for and
would appreciate help on this.

To a first approximation, look at the lumen output figures for the
different lamps.

One important thing this doesn't take into account are the losses
in the luminare. Yours probably have reflectors to redirect most
of the light out of the front, but these are never 100% efficient
(or anywhere close). This is where LEDs have an advantage as they
are implicitly directional (to varying degrees), so don't tend to
lose as much light inside the luminare.

Another important area is what proportion of the light is directed
where you need it, and how much is lost in spillage over areas you
don't need (or want) to light up. Again, because of the much smaller
light source in LEDs, it's possible to focus the beam much more
accurately so more of the light is directed where it's needed and
less wasted.

LED streetlighting downsides - they currently seem to be significantly
less reliable than they should be. This may be because many companies
have entered this area with little experience in producing electronics
for outdoor street furniture. I've seen a number of local authorities
install and then give up on LED streetlighting, when they turn out not to
live up to their longevity claims. Some of the manufacturers have responded
to this by guaranteeing to replace their products (including doing the
on-site installation) if they fail, although that's not practical in all
cases (e.g. a motorway where planning and night time lane closures need
to be put in place, at vastly more cost than the luminare replacement
itself).

The 400watters could be replaced by 2x 200/250w (MH-led) equivalents. This
might prove a bonus in terms of better coverage.

Any thoughts please on led output comparisons and perhaps suppliers of
suitable luminaires?

I would wait a bit if you can - I think the LED products will rapidly
get better as more local authorites try to roll out LED lighting, and
the less reliable products naturally disappear from the marketplace.

--
Andrew Gabriel
[email address is not usable -- followup in the newsgroup]

"Andrew Gabriel" wrote in message
...
In article ,
"Nick" writes:
The open areas of our works are floodlit. Originally incandescent, then
tungsten and now metal halide.
We use 150w, 250w & 400w mh lamps. All on 9m stands and operated by
dusk/dawn sensors. Some of these lamps are now again degraded.
I am thinking that these metal halides would 'roughly' equate to 500, 750
and 1000w tungsten lamps.

That's probably not far off (although when you get to 1000W mains
filament lamps, they are significantly more efficient than 100W
and lower lamps).

Thinking of converting to led. Not for greenery but for (1) reduced
running
cost and (2) ease of replacement as I'm the one one that maintains them.
Never have had much fondness of heights.
I haven't a clue as to what size led replacements I might be looking for
and
would appreciate help on this.

To a first approximation, look at the lumen output figures for the
different lamps.

One important thing this doesn't take into account are the losses
in the luminare. Yours probably have reflectors to redirect most
of the light out of the front, but these are never 100% efficient
(or anywhere close). This is where LEDs have an advantage as they
are implicitly directional (to varying degrees), so don't tend to
lose as much light inside the luminare.

Another important area is what proportion of the light is directed
where you need it, and how much is lost in spillage over areas you
don't need (or want) to light up. Again, because of the much smaller
light source in LEDs, it's possible to focus the beam much more
accurately so more of the light is directed where it's needed and
less wasted.

LED streetlighting downsides - they currently seem to be significantly
less reliable than they should be.

What a surprise.

And only 10 years ago CFLs for household lighting was going to save the
world:-)

This may be because many companies
have entered this area with little experience in producing electronics
for outdoor street furniture. I've seen a number of local authorities
install and then give up on LED streetlighting, when they turn out not to
live up to their longevity claims. Some of the manufacturers have
responded
to this by guaranteeing to replace their products (including doing the
on-site installation) if they fail, although that's not practical in all
cases (e.g. a motorway where planning and night time lane closures need
to be put in place, at vastly more cost than the luminare replacement
itself).

Care to name and shame? At least the LED lights I fitted at Collingham train
station car park can be lowered to allow the LED head to be changed if it
fails.

--
Adam

Nick wrote:
The open areas of our works are floodlit. Originally incandescent, then
tungsten and now metal halide.
We use 150w, 250w & 400w mh lamps. All on 9m stands and operated by
dusk/dawn sensors. Some of these lamps are now again degraded.
I am thinking that these metal halides would 'roughly' equate to 500, 750
and 1000w tungsten lamps.
Thinking of converting to led. Not for greenery but for (1) reduced running
cost and (2) ease of replacement as I'm the one one that maintains them.
Never have had much fondness of heights.
I haven't a clue as to what size led replacements I might be looking for and
would appreciate help on this.

The 400watters could be replaced by 2x 200/250w (MH-led) equivalents. This
might prove a bonus in terms of better coverage.

Any thoughts please on led output comparisons and perhaps suppliers of
suitable luminaires?
Thanks,
Nick.




in answer to the subject line.
http://www.ebay.com/itm/200-000-Lux-...em2c8826037 4

http://tinyurl.com/psqadze

On Thursday, November 27, 2014 7:27:09 PM UTC, Nick wrote:
The open areas of our works are floodlit. Originally incandescent, then
tungsten and now metal halide.
We use 150w, 250w & 400w mh lamps. All on 9m stands and operated by
dusk/dawn sensors. Some of these lamps are now again degraded.
I am thinking that these metal halides would 'roughly' equate to 500, 750
and 1000w tungsten lamps.
Thinking of converting to led. Not for greenery but for (1) reduced running
cost and (2) ease of replacement as I'm the one one that maintains them.
Never have had much fondness of heights.
I haven't a clue as to what size led replacements I might be looking for and
would appreciate help on this.

The 400watters could be replaced by 2x 200/250w (MH-led) equivalents. This
might prove a bonus in terms of better coverage.

Any thoughts please on led output comparisons and perhaps suppliers of
suitable luminaires?
Thanks,
Nick.

You could get one example of each lamp and measure the light on the ground with a meter:
http://www.amazon.co.uk/Pocket-Light...ds=light+meter

There are Android apps which do something similar but hardly worth using.


rusty

On Friday, November 28, 2014 9:04:30 AM UTC, therustyone wrote:
On Thursday, November 27, 2014 7:27:09 PM UTC, Nick wrote:
The open areas of our works are floodlit. Originally incandescent, then
tungsten and now metal halide.
We use 150w, 250w & 400w mh lamps. All on 9m stands and operated by
dusk/dawn sensors. Some of these lamps are now again degraded.
I am thinking that these metal halides would 'roughly' equate to 500, 750
and 1000w tungsten lamps.
Thinking of converting to led. Not for greenery but for (1) reduced running
cost and (2) ease of replacement as I'm the one one that maintains them.
Never have had much fondness of heights.
I haven't a clue as to what size led replacements I might be looking for and
would appreciate help on this.

The 400watters could be replaced by 2x 200/250w (MH-led) equivalents. This
might prove a bonus in terms of better coverage.

Any thoughts please on led output comparisons and perhaps suppliers of
suitable luminaires?
Thanks,
Nick.

You could get one example of each lamp and measure the light on the ground with a meter:
http://www.amazon.co.uk/Pocket-Light...ds=light+meter

why, when lamps are labelled with lumen output?

NT

In article ,
therustyone wrote:
You could get one example of each lamp and measure the light on the
ground with a meter:

I'd recommend this too. Makers tend to lie through their teeth when giving
light levels from the latest whizz bang technology.

--
*Women who seek to be equal to men lack ambition.

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

On 28/11/2014 11:15, Dave Plowman (News) wrote:
In article ,
therustyone wrote:
You could get one example of each lamp and measure the light on the
ground with a meter:

I'd recommend this too. Makers tend to lie through their teeth when giving
light levels from the latest whizz bang technology.

Just a thought, maybe I will get shot down inflames, but could not a
camera light meter be used?

In article ,
Broadback wrote:
On 28/11/2014 11:15, Dave Plowman (News) wrote:
In article ,
therustyone wrote:
You could get one example of each lamp and measure the light on the
ground with a meter:

I'd recommend this too. Makers tend to lie through their teeth when
giving light levels from the latest whizz bang technology.

Just a thought, maybe I will get shot down inflames, but could not a
camera light meter be used?

Yes - a decent incident light meter should do the job.

--
*I finally got my head together, now my body is falling apart.

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

On Fri, 28 Nov 2014 11:15:06 +0000 (GMT), "Dave Plowman (News)"
wrote:

In article ,
therustyone wrote:
You could get one example of each lamp and measure the light on the
ground with a meter:

I'd recommend this too. Makers tend to lie through their teeth when giving
light levels from the latest whizz bang technology.

Yes, it's always sensible to make your own _independent_ comparisons
between the old (reference lamp type) and the new "Wizz Bang"
replacement that purports to be a power saving equivilent.

If you're comparing an existing lamp (or lamp type) against your
latest purchase, you can use a P&S digital camera to gain some numeric
data. The usual method is to set the camera to aperture priority and
take a picture of the area of interest lit primarily by your lamp
source(s), ideally with little to no light pollution from other
sources.

Generally, most digital cameras can select a finer increment in
selected shutter speeds than they can for aperture settings. If it
turns out that the camera chooses the same exposure values, you can
compare each picture to detect which, if any, was just marginally the
brightest of the two.

For example, when I purchased an 810 Lumen 12W LED lamp from Asda a
few weeks back for the princely sum of £3.49 to replace the LES 20W
CFL in the adjustable pendant fitting above the dining table in our
kitchen diner, I was able to note that the LED lit scene looked just
that little bit brighter when the exposures chosen by the camera had
been exactly the same in both cases.

Using the digital camera removed the element of guesswork in trying
to rely upon direct observation alone to determine whether or not I
was losing out on illumination levels in switching to the lower
wattage LED lamp.

Unless you need to collect actual illumination data to a specific
accuracy of measurement, there's no real benefit to be gained in
spending money on a light meter when simply comparing different lamp
types against each other using a digital camera will tell you all you
really need to know.
--
J B Good

In article ,
"Dave Plowman (News)" writes:
In article ,
therustyone wrote:
You could get one example of each lamp and measure the light on the
ground with a meter:

I'd recommend this too. Makers tend to lie through their teeth when giving
light levels from the latest whizz bang technology.

Make sure you run a lamp for 100 hours before measuring.
Some lamp technologies are slightly brighter when brand new.

All lamp technologies slowly get dimmer with age, so you will get a
misleading reading if you compare one newish lamp with one near end
of life.

--
Andrew Gabriel
[email address is not usable -- followup in the newsgroup]

In article ,
Andrew Gabriel wrote:
I'd recommend this too. Makers tend to lie through their teeth when
giving light levels from the latest whizz bang technology.

Make sure you run a lamp for 100 hours before measuring.

Thought that was to allow a CFL to achieve full level on a cold day? ;-)

Some lamp technologies are slightly brighter when brand new.

All lamp technologies slowly get dimmer with age, so you will get a
misleading reading if you compare one newish lamp with one near end
of life.

--
*Upon the advice of my attorney, my shirt bears no message at this time

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

On 28/11/2014 14:40, Broadback wrote:
On 28/11/2014 11:15, Dave Plowman (News) wrote:
In article ,
therustyone wrote:
You could get one example of each lamp and measure the light on the
ground with a meter:

I'd recommend this too. Makers tend to lie through their teeth when
giving
light levels from the latest whizz bang technology.

Just a thought, maybe I will get shot down inflames, but could not a
camera light meter be used?

There are apps for mobile phones...

Have no idea as to their accuracy, reproducibility, etc.

--
Rod

On Sat, 29 Nov 2014 11:33:01 +0000 (GMT), "Dave Plowman (News)"
wrote:

In article ,
Andrew Gabriel wrote:
I'd recommend this too. Makers tend to lie through their teeth when
giving light levels from the latest whizz bang technology.

Make sure you run a lamp for 100 hours before measuring.

Thought that was to allow a CFL to achieve full level on a cold day? ;-)

I saw the smiley but Andrew was referring to the fact that a low
pressure mercury vapor discharge fluorescent tube starts off at around
a 110% of its 'design lumens' before swiftly dropping down to 100%
during the first thousand hours or so of an 8 to 16 thousand hour
design life when the output will have dropped to something like 80%
before the drop is considered to be end of life.

The light output plotted against time follows an exponential curve
where most of the initial drop to 105% takes place in the first
hundred hours or so. The mechanism for the loss of efficacy in such
lamps, istr, is largely to do with mercury argon 'poisening' of the
fluorescent coating.

White LED lamps which use a blue LED to excite the phosphor coating
must also suffer some loss of efficacy in the flourescent material
used but, with lifetime ratings typically in the 30 to 50 thousand
hour range, the rate at which the efficacy of the phosphor coating
drops must be far lower than in the case of a mercury vapour
fluorescent, presumably on account of the lack of such a 'poisening'
mechanism.


Some lamp technologies are slightly brighter when brand new.

Yeah, fluorescent lamps as described above.

All lamp technologies slowly get dimmer with age, so you will get a
misleading reading if you compare one newish lamp with one near end
of life.

That's true enough. I think the least effected by ageing during their
rated lifetimes are the standard gas filled tungsten filament lamps,
particularly when burning 'cap up' in pendant fittings.

I haven't seen any lifetime light output plots for phosphor coated
blue LED lamps but I assume these are also based on the 80% of design
lumens end of life criterium.

When I did my comparison test using a digital camera, comparing a 12W
LED against an existing 20W CFL, I felt pretty confident that the CFL
had only clocked up 1 or 2 thousand hours so was within a percent or
two of its design lumen output. I took care to allow the lamp to
thoroughly warm up to its final steady state operating temperature (10
minutes or so warm up time). The only "unknown" in this case being how
much brighter than design lumens a factor, if any, applies to such LED
lamps.

Since the old CFL has been put to one side, I can repeat the
comparison say every 6 months or so and look for such an initial lumen
efficacy drop mechanism in the LED lamp (the unused CFL should provide
a constant reference source to ensure meaningful results).

Another thing to bear in mind with modern LED lamps (apart from the
effect of colour temperature on the efficacy of its lumen ouptut
rating) is the tungsten filament lamp type used as the comparison
reference.

For example, you may see them compared to a "60W 810 lumen" tungsten
filament lamp. This is only true for the American 117v 750 hour rated
incandescent GLS lamp which is equivilent to a 75W 1000 hour 240v
tungsten filament GLS lamp, not a commonly available lamp size here in
the UK.

As it happens for once, a difference that makes the efficiency
improvement of LED based lamps over the 220 and 240 volt tungsten
filament GLS lamps used here and in Europe even greater than that
experienced by our Yankee cousins. :-)
--
J B Good

In article ,
Johny B Good wrote:
Thought that was to allow a CFL to achieve full level on a cold day? ;-)

I saw the smiley but Andrew was referring to the fact that a low
pressure mercury vapor discharge fluorescent tube starts off at around
a 110% of its 'design lumens' before swiftly dropping down to 100%
during the first thousand hours or so of an 8 to 16 thousand hour
design life when the output will have dropped to something like 80%
before the drop is considered to be end of life.

Very true. However, my limited experience of mains LEDs is they never get
anywhere near their claimed life before failing. And they are more costly
than a CFL.

--
*CAN AN ATHEIST GET INSURANCE AGAINST ACTS OF GOD?

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

On Sat, 29 Nov 2014 14:23:55 +0000 (GMT), "Dave Plowman (News)"
wrote:

In article ,
Johny B Good wrote:
Thought that was to allow a CFL to achieve full level on a cold day? ;-)

I saw the smiley but Andrew was referring to the fact that a low
pressure mercury vapor discharge fluorescent tube starts off at around
a 110% of its 'design lumens' before swiftly dropping down to 100%
during the first thousand hours or so of an 8 to 16 thousand hour
design life when the output will have dropped to something like 80%
before the drop is considered to be end of life.

Very true. However, my limited experience of mains LEDs is they never get
anywhere near their claimed life before failing. And they are more costly
than a CFL.

That's very true in regard to their regular pricing. My experience is
probably a lot more limited than yours in regard to lamp life.

I've only bought two during the past year, a 5W 270 Lumen BC
'classic' shape 'bulb' for a fiver last year and a 12W 810 Lumen
'bulb' for £3.49 earlier this month, both from our local Asda
Superstore as it happened.

I suspect the 12W lamp has already clocked more hours than the 5W
lamp simply because I eventually installed it in the basement landing
area in a ceiling batten fitting just by the electric meter where it
probably never sees more than half an hour's use per week on average.

Since that 5 watter is operating in the coolest part of the house,
unencumbered by any form of lamp shade, it stands the best chance of
living up to the maker's 25,000 hour life rating claim. At the current
usage rate, there's every chance I'll be dead and cremated before it's
clocked its first thousand hours. Even if I decide to leave it running
24/7, it's going to take nearly 3 years before it reaches the 25000
hour mark.

The 12W lamp, otoh, is probably going to average 4 to 6 hours a day,
roughly 6 months per 1000 hours of lamp life. Assuming 2000 hours a
year usage, that's a 12 year lifetime based on a 25000 hour life
rating.

Thus far, I've not experienced any premature mains voltage LED lamp
failures (but it's _very_ early days and a sample size of only two
lamps).

Let's face it, with such extended life claims, any failures within 2
years of purchase are a guaranteed indicator for premature failure
even if the lamps in question where left permanently lit after being
installed.

Only this afternoon, I was in the "Home Bargain" shop with the
missus, contemplating increasing the sample size to 3. I was looking
at a 7W 620 lumen BC example they had on the shelf for £4.99 (same
efficiency level as the 15 quid 810 lumen 10W LES lamp in our local
Asda superstore).

In the end, I resisted the temptation based on my feeling that I
would be joining the "Early Adopters'" club and paying a premium price
for the priviledge.

A year ago, I would have snapped it up (and the other remaining BC
example out of a pile of LES lamps) at that price but, ever since
purchasing that 12W 810 Lumen lamp at the beginning of the month in
Asda for a 'mere £3.49', my LED lamp bargain price point reference has
now slid down to a new low.

I'm older and wise enough to know better than to play that game of
"Early Adoption" to start over-investing in an immature technology
that still has a few more years to go before it hits the limits on
efficacy and mass production led pricing levels. I've still got an
ample supply of CFL 'spares' to see me through the next couple of
years so I can afford to play the waiting game. :-)

However, that won't stop me being on the look out for more LED Lamp
Bargains. It's one thing to blow 3 or 4 quid on a single LED bulb but
another one entirely when it comes to replacing the ten 7W SES CFL
candle lamps in our two chandeliers at a price of £3.99 each to the
tune of 10p shy of a 40 quid investment in the 7W LEDs currently on
the shelves of Home Bargain.

I've no doubt that in a years time I'll be seeing 5W versions of
equal or higher brightness SES candle lamps a quid or two cheaper.
Others might argue, as they often have with computer technology, that
there'll always be a better value product on the horizon and you face
the risk of your purchase becoming dated or worse still, obsoleted no
matter how much you delay. That's a valid argument for Personal
Computers and all the spin off technoligies (smartphones, tablets etc)
but not so for something like a more efficient lamp which has definite
and well defined limits on its performance.

From the press releases issued early this year by Philips and Cree we
can expect to finally see real product on the shelves in another 12
months time with triple the efficiency of the CFL (or only double that
of an electronically ballasted linear fluorescent tube) at which point
the manufacturers will be well and truly into 'Diminishing Returns'
territory.

Next year's "Early Adopters" are not going to have their smug smiles
of satisfaction wiped off their faces as swiftly as today's early
adopters when the next round of lighting technology development makes
its appearance.

I reckon that in about 12 months time, we'll have reached that point
where the returns on running costs will finally justify the capital
investment in LEDs with a very much reduced obsolescence risk factor
to boot.

There will no doubt be better lamps available in the years succeeding
next but the improvements will be more marginal than we know is the
case today. Furthermore, the pace of such improvement will be slowed
right down to a snail's pace compared to what we've witnessed during
the last 5 years or so (and promised over the next 12 months).

By all means, snap up those odd bargains you might see from time to
time where you know exactly where you're going to usurp an existing
CFL or even an incandescent lamp to maximum benefit (but I'd hold off
on a mass LED upgrade for another 12 months if I was you).


Incidently, it's just occurred to me that your problem of premature
lamp failure could be due to overheating. Unlike tungsten filament
lamps that can and do run at 200 degrees and higher temperatures in
conventional lamp fittings which allows them to dissipate their 60
watts of waste heat with ease, LEDS are limited to a much lower
maximum temperature (80 to 120 deg C ?) and can overheat in poorly
ventillated fittings rated for 40 and 60 watt incandescent GLS lamps,
especially when the lamp is burning cap up.

It's a limitation that's not so apparent when the lamp is quite
obviously meant to be a "Drop In" replacement for the good old
fashioned tungsten lamp. The thing to look out for is a lack of
ventillation such as happens with some lamp shades and pendant
fittings. Such fittings result in a nice cosy blanket of hot air
surrounding the base of the lamp where the electronic ballast
components live (or die).

The later more efficient lamps will be less prone to this overheating
hazard since they generate less waste heat per lumen of output. This
is one of the main factors that limited the earlier lamps to quite
modest lumen ratings. It's only now that we're starting to see lamps
with more useful outputs of 810 (and even higher) lumens (60W American
/ 75W UK GLS filament lamp types). This yet another good reason to
hang back before 'blowing your wad' on a whole house relamping
upgrade.
--
J B Good

On Mon, 01 Dec 2014 00:46:59 +0000, Johny B Good wrote:

snip
It's only now that we're starting to see lamps
with more useful outputs of 810 (and even higher) lumens (60W American
/ 75W UK GLS filament lamp types). This yet another good reason to
hang back before 'blowing your wad' on a whole house relamping
upgrade.

Although I've bought a few LED lamps (up until a week ago, 7. They're for
places where CFLs aren't too good: desk lights (CFLs too heavy), long-use
lights where output isn't important and 2 outside where CFLs take too long
to warm up) I've been holding off until at least the 5050 etc. sizes have
gone.

In a small room (about 2x3m) there was an 11W cfl in a quite translucent
glass shade; it was good and bright and gave plenty of light, but I did, of
course, cast a shadow everywhere I wanted to see.

Taking into account the need for at least some spread at source, I bought a
3-armed fitting in a bronze(y) finish (I hate chrome plate), deliberately
choosing one that takes SES (E14) rather than the more common G9.
The horizontal lampholders avoid the dark area of LEDs (and CFLs) being up
to the ceiling and mean that the base of the lamps don't get so hot.
http://www.amazon.co.uk/Antique-Bras.../dp/B00LMFXRY8
Fortunately the tool provided for fitting the shades' retaining rings also
handles the lamps.

Now, I'd sort of picked the lamps first. I was looking for 80lm/W output
and a design that spread both the light and the heat. Found these little
beasties:
http://www.amazon.co.uk/Ledlam-E14-3...dp/B00L6LQ0K6/
so 9W of LED at (nominally) 960lm total - rather better than the 880lm of a
good CFL initially.

BTW, these look good also:
http://www.amazon.co.uk/Ledlam-E27-5...dp/B00L6LQXEO/
A couple of days ago there were som 6W 720lm in the same format but they
seem to have gone out.

Although the shades are a bit less translucent than I'd like them to be, the
output seems a lot better than the 11W CFL and of course no warm up.

I have several places where the CFL is overpowered so that I don't have to
wait and see.
--
Peter.
The gods will stay away
whilst religions hold sway

On Fri, 28 Nov 2014 02:41:41 -0800 (PST), wrote:


why, when lamps are labelled with lumen output?

hollow laugh
Very few aren't lying *******s.