LED light bulbs

elstimpo

zeupater wrote: »

Hi

Don't you really think that to an outsider it looks really odd that the point is being argued in such a manner? ... is it not also the case that a self confessed industry insider with the kind of credentials stated previously wouldn't know their own marketplace, competitors, customers and competitive products & technologies to such a degree that when what is likely the highest volume national shifter of LED lighting in combination with a particular product line description is mentioned the actual product and it's specification wouldn't almost immediately come to mind ? ....

Of course your argument is based on intensity & colour as logic would state that low intensity & poor colour either wouldn't result in a high CRI or couldn't deliver the qualitative benefits which a high CRI is claimed to deliver.

What really needs to be realised is that a high CRI 11W/810 lumen LED lightbulb with a 25000Hr life expectancy costing £12.98 will cost 52p/1000Hrs (12.98/25) and deliver the same amount of light into a dark room as a 9W/806 lumen LED lightbulb with a 15000Hr LE purchased in packs of 5 for £10 which cost 13p/1000Hrs (2/15) ..... of course, the higher efficiency of the cheaper bulbs also needs to be accounted for, so that's simple ... 11kWh/1000Hrs (~£1.32) vs 9kWh/1000Hrs (~£1.08). Above that, around 810 lumen in a standard room fitting will deliver light which may be good enough to see by (~50lux ?), but you're certainly not going to be able to distinguish colours as well as in bright daylight (10000lux+) anyway, so unless there's literally hundreds of domestic lightbulbs in the equation then it's doubtful that anyone would really be able to tell the difference between standard LED and high CRI bulbs anyway ...

Of course, you'll 'know' different ... but looking at the logic employed and the numbers falling out of some pretty solid calculations, you're probably not doing your business prospects much good here ...

HTH
Z

This is absolutely ludicrous. I literally have no idea what you are talking about in paragraph one. None at all. Do explain please.

Would you mind clairfying what you mean by 'light intensity'?

Would you also mind clarifying what 'same amount of light' also means please?

Higher efficiency of the cheaper lamp or an LED Chip that is being stressed to produce more lumens? So it's far from simple, in fact it's pure guess work on your behalf.

810 lumens at 2700k is equivalent to a 60w incandescent, so more than enough brightness to see by.

No, no LED Lamp is going to distinguish colours as well as bright daylight. I don't understand the relevance of this point? Lamps of all kinds are generally used when there is little to no bright daylight. So i'm at a loss on this one?

Are you really arguing that significantly differing R values in the CRI spectrum cannot be detected from 1 lamp to another? If so, thats factually incorrect backed up by every research and testing paper ever published on the subject. That's why i 'know' different.

I also strongly disagree that your 'solid calculations' are solid or that your 'logic' makes any sense.

I'm not looking for any 'business prospects' by posting on this forum. I come on to post facts and my opinions on LEDs in order to help people make informed buying decisions.

I've never named my company on this forum and have even gone as far as recommending my competitors in order to help people buy quality products. The likes of Soraa and Collingwood for example.

I highly recommend reading a lot of the testing reports and papers that Soraa publish around CRI !

In fact there will be shift away from CRI as a measurement of defining colour rendition soon. They tried with CQS but it failed and now we have TM-30, which gives far more information and accuracy and it shoukld replace CRI soon.

elstimpo

Martyn1981 wrote: »

What qualifications are needed?

I buy a lamp, I'm happy with the lamp, and it's extremely good value. Job done.

Your qualifications are of no importance whatsoever within the context of the thread and discussions prior to you joining.

Once again, why can't I have an opinion on a car, without being a formula 1 driver?

Do you attack everyone that gives a product review online on the basis that they are not qualified enough to have an opinion on whether they are happy or not with a product?

I haven't responded to your list of responses as I found them to be nonsense. You even continued your argument about £5 lamps despite it never having any link to what I was saying.

If you want value for money try this:-

I pay £1.50 to £2.00 for a lamp today and am perfectly happy. It dies after 10yrs (failing to meet a suggested 15yr promise), then I buy a high quality one for £3 (£2 in today's money), which lasts 15yrs. I'm in the hole for £4 or less and get 25yrs, whilst you pay £6 or so today for the 15yr bulb I buy in 2027. Who's the mug?

Once again, can I suggest you re-read the thread, you are simply maintaining an argument that nobody else (apart from almillar) is involved in.

When you buy a lamp you have absolutely no idea if it's good value or not.

I don't know anything about Formula 1. I can have an opinion on it, but i wouldn't be ignorant or arrogant enough to believe my opinion is worth anything or even remotely accurate.

Those calculations are ridiculous and based only on your guess work that is easily discredited by the many published & credible testing reports available from numerous companies and organisations.

What a complete waste of time. :mad:

elstimpo

EricMears wrote: »

My only interest in this topic is in waiting to see when the penny will drop that there's a lot of 'trolling' going on

The penny has dropped. It's the only explantion for some of the 'calculations' and 'logic' being posted.

ASavvyBuyer

It is very dissapointing to learn that the Home Bargains 4 watt LED's that I bought 5 years ago for £2.99 each to replace the 35 watt Halogen spots in the kitchen in the old house (and moved to our new home) are such bad quality.

They have provided a similar light level that we are very happy with (although I don't try to achieve the same quality of light that I would have done when doing the lighting for a TV studio or stage).

On the usual estimate of an average 2 hours a day use they have already saved nearly 4 times what they cost in electricity charges.

I just hope that the screwfix LED spots that I purchased (5 for £3.50), for some extra lighting in the larger kitchen, perform just aswell and last as long.

lstar337

elstimpo wrote: »

In fact there will be shift away from CRI as a measurement of defining colour rendition soon. They tried with CQS but it failed and now we have TM-30, which gives far more information and accuracy and it shoukld replace CRI soon.

The general public must be on the edge of their seats!

Dave_Fowler

I think a new thread should be opened titled 'Cheap LED lamps' so that a discussion on this Money Saving forum can continue along those lines without being confused with the recent discussions of light quality and other such related topics. It is all too easy for a thread to be thrown off its original course.

Dave F

Martyn1981

elstimpo wrote: »

I don't know anything about Formula 1. I can have an opinion on it, but i wouldn't be ignorant or arrogant enough to believe my opinion is worth anything or even remotely accurate.

You've completely dodged the issue, and I find it hard to believe that was by accident, I've said it twice, but here goes number three.

I don't have to be a formula 1 driver (expert in driving or car handling) to have an opinion on the car I drive. I don't have to be an expert on lighting to have an opinion on the amount of light in my room, nor the quality that I (I - note the I) enjoy.

So I'm not asking for an expert opinion on Formula 1, and I doubt that's how you read what I posted.

Perhaps Eric is right, dodging and twisting is a give away.

Martyn1981

Cardew wrote: »

Yesterday in Screwfix I bought a pack of 5 of these for £9.99:

http://www.screwfix.com/p/lap-gls-led-lamps-white-bc-9w-5-pack/8621j#product_additional_details_container

According to this morning's e-mail, the sale/clearance is still on, and they are selling for £5.99 for a pack of 5. Stock checker showed 10+ in all local stores .......... then I noticed the deal is only on ES lamps not BC. Bit of a sod!

almillar

Why do I have to supply you with information to get you to stop lying about me? Nobody asked you to spread false information about what I'd bought, how I live, and how bright my lights are.

Hold on, you're getting things out of order. You started the thread talking about £1.50 lamps, I asked the specs. You wouldn't state them, so I speculated. I don't recall any lies, and you seem to like emotive language, and taking a discussion about LEDs very personally. Nor did I spread any false information. If you start a thread about LEDs, shouldn't you reasonably expect people to ask questions about them?

Again, simply lying about what I've said. Where have I said you can replace a 100W lamp with a 400lm LED? You've simply made it up ..... again.

I lied about nothing. You did not say that. I did not say you said that. I'm giving an example of why you should check what you're replacing first. You want to just replacing everything with what turned out to be an 806 lumens bulb. That's too bright for some situations BTW ;-)

You didn't say cheap stuff 'could' be junk, you implied it was all junk:

"What lumens do they put out? What colour temperature are they? What is their CRI?
I bet they put out nothing like the quality of light of the incadescent or CFL bulbs they're 'replacing'."

This is not me claiming that ALL cheap LEDs are junk. This was me 'betting' that YOURS were junk, because you hadn't said what they were. I was referring specifically to the ones you were recommending, and once you provided the info, turned out to be wrong.

So to stop lying you demand information, but now you run away when asked what the lamps were that you thought we should be buying.

Again you've got it out of order - I was demanding information before I was 'lying'! You repeatedly miss my point that I'm not recommending one single lamp that everyone should immediately buy, because all uses are different! You just recommended people walk into one of 3 stores and buy their lamps. Which ones?! Was my only question!

Perhaps you never had any in mind whatsoever,

I told you that several times. I actually don't think you're reading what I say.

of adding to the debate (rather than spreading lies) whatsoever?

The contribution I was making has been repeated several times, but you've taken it as a personal attack, and I'll not waste everyone's time repeating it again.

It is very dissapointing to learn that the Home Bargains 4 watt LED's that I bought 5 years ago for £2.99 each to replace the 35 watt Halogen spots in the kitchen in the old house (and moved to our new home) are such bad quality

Yes, nice specific information. If it was 50w spots you were replacing, you might have found the LEDs disappointingly dim.

I think a new thread should be opened titled 'Cheap LED lamps'

We should call it 'Good Cheap LED lamps'. Then we can separate the good ones from the bad ones and exchange experience.

zeupater

elstimpo wrote: »

zeupater wrote: »

Hi

Don't you really think that to an outsider it looks really odd that the point is being argued in such a manner? ... is it not also the case that a self confessed industry insider with the kind of credentials stated previously wouldn't know their own marketplace, competitors, customers and competitive products & technologies to such a degree that when what is likely the highest volume national shifter of LED lighting in combination with a particular product line description is mentioned the actual product and it's specification wouldn't almost immediately come to mind ? ....

Of course your argument is based on intensity & colour as logic would state that low intensity & poor colour either wouldn't result in a high CRI or couldn't deliver the qualitative benefits which a high CRI is claimed to deliver.

What really needs to be realised is that a high CRI 11W/810 lumen LED lightbulb with a 25000Hr life expectancy costing £12.98 will cost 52p/1000Hrs (12.98/25) and deliver the same amount of light into a dark room as a 9W/806 lumen LED lightbulb with a 15000Hr LE purchased in packs of 5 for £10 which cost 13p/1000Hrs (2/15) ..... of course, the higher efficiency of the cheaper bulbs also needs to be accounted for, so that's simple ... 11kWh/1000Hrs (~£1.32) vs 9kWh/1000Hrs (~£1.08). Above that, around 810 lumen in a standard room fitting will deliver light which may be good enough to see by (~50lux ?), but you're certainly not going to be able to distinguish colours as well as in bright daylight (10000lux+) anyway, so unless there's literally hundreds of domestic lightbulbs in the equation then it's doubtful that anyone would really be able to tell the difference between standard LED and high CRI bulbs anyway ...

Of course, you'll 'know' different ... but looking at the logic employed and the numbers falling out of some pretty solid calculations, you're probably not doing your business prospects much good here ...

HTH
Z

This is absolutely ludicrous. I literally have no idea what you are talking about in paragraph one. None at all. Do explain please.

Would you mind clairfying what you mean by 'light intensity'?

Would you also mind clarifying what 'same amount of light' also means please?

Higher efficiency of the cheaper lamp or an LED Chip that is being stressed to produce more lumens? So it's far from simple, in fact it's pure guess work on your behalf.

810 lumens at 2700k is equivalent to a 60w incandescent, so more than enough brightness to see by.

No, no LED Lamp is going to distinguish colours as well as bright daylight. I don't understand the relevance of this point? Lamps of all kinds are generally used when there is little to no bright daylight. So i'm at a loss on this one?

Are you really arguing that significantly differing R values in the CRI spectrum cannot be detected from 1 lamp to another? If so, thats factually incorrect backed up by every research and testing paper ever published on the subject. That's why i 'know' different.

I also strongly disagree that your 'solid calculations' are solid or that your 'logic' makes any sense.

I'm not looking for any 'business prospects' by posting on this forum. I come on to post facts and my opinions on LEDs in order to help people make informed buying decisions.

I've never named my company on this forum and have even gone as far as recommending my competitors in order to help people buy quality products. The likes of Soraa and Collingwood for example.

I highly recommend reading a lot of the testing reports and papers that Soraa publish around CRI !

In fact there will be shift away from CRI as a measurement of defining colour rendition soon. They tried with CQS but it failed and now we have TM-30, which gives far more information and accuracy and it shoukld replace CRI soon.

Hi

I doubt that addressing the points will make much difference (although it should), but, in order ....

"I literally have no idea what you are talking about in paragraph one. None at all. Do explain please. " ... well pretty simple really, you've identified yourself as an industry insider and it's pretty simple to deduce from previous self-importance brags who you actually claim to be and therefore which company specialising in high CRI LED products you are associated with. As for competitor and competitor product awareness the paragraph speaks for itself as any reasonable person would naturally expect any company to be conducting marketplace analysis ...

"Would you mind clairfying what you mean by 'light intensity'? " ... really ? ... surely you understand the difference between intensity (concentration/brightness) in terms of source lumens or illuminated lux, or possibly even the base SI measurement candela ? ... whichever is used is irrelevant as long as application is consistent.

"clarifying what 'same amount of light' also means please?" ... again, really ? ... as you already should be aware, it doesn't matter how you want to compare as long as the same basis is used, so candela, lux, lumens, irradiation - in terms of surface area illumination, which is really what most would be interested in, then the sensible measure would be lux. Now we have a definition of light falling on an object it becomes possible to quantify the 'amount' by considering the variable of time ... so measuring the light from two sources over time would quantify the 'amount of light' and if your claims are realistic, you should already know this.

"Higher efficiency of the cheaper lamp or an LED Chip that is being stressed to produce more lumens? So it's far from simple, in fact it's pure guess work on your behalf." ... Absolute rubbish ... the efficiency difference could just as easily be down to supporting electronics or the technology differential behind producing the high CRI light-source. As for the guesswork, well considering that the MTBF for both products would be the basis of the published life expectancies then we have a quantifiable comparison .. 15000Hrs vs 25000Hrs, suggesting that the MTBF calculation may have already taken consideration of higher operating temperature on components in the 'cheaper' alternative ...

"810 lumens at 2700k is equivalent to a 60w incandescent, so more than enough brightness to see by." ... depending on distance from source of course! ... but that's already agreed and therefore is not the issue - the point raised, but overlooked, is "810 lumen in a standard room fitting will deliver light which may be good enough to see by (~50lux ?), but you're certainly not going to be able to distinguish colours as well as in bright daylight" ... therefore why invest in quality of light when at a surface illumination level of ~50lux it would be almost impossible to distinguish the difference - at significantly higher levels it may well make a difference, but at around 50lux ? ...

"Are you really ..." ... but, as you 'know', that's not the point at hand. We're not talking lab test conditions or opinions of reflected colours in an artificially created environment ... what we are discussing is the ability of the average human eye to distinguish a difference in reflected surface colour between two different light sources at levels of around 50lux .. above that, the ability of the human brain to process and recognise that difference and to not compensate, and above that, not have the two light sources provided in a manner to directly compare, side-by-side ...

"I also strongly disagree that your 'solid calculations' are solid or that your 'logic' makes any sense" ... :rotfl:.... then show us all where they're not solid ! ... the variables for the bulbs are published lumens, published life expectancy & unit price from a major retailer and what looks to be your own website, with energy being cost/kWh ... of course, the lux level in every room will be subject to differences depending on distance from source, incidence angles, reflections etc, but levels of around 50lux would seem to be typically for the UK domestic environment although a single 810lumen B22 light would struggle to achieve/exceed anywhere near this on all but nearby surfaces in almost any room ... so, expose the shaky foundation in the calculation or logic and astound us all ...

"I come on to post facts and my opinions on LEDs in order to help people make informed buying decisions." ... fine, but the 'facts' need to be relevant and the opinions unbiased ... the quality of light delivered by a high CRI light-source may be measurable and therefore objective with numerous application where necessary, however, translating this to being able to distinguish the difference in a domestic environment at normal levels of illumination with no test equipment moves well into the subjective arena .... facts, depending on variables such as environment & application, are not always relevant ...

".. have even gone as far as recommending my competitors in order to help people buy quality products" ... this may be the case, however what needs to be realised is that quality is both price sensitive and in many cases an extremely subjective measure which is aggressively used by many suppliers when marketing and promoting product ... for example a calculated MTBF of 15000Hrs for a bulb costing £2 may be just as inaccurate as one of 25000Hrs for a unit costing 6.5x more, however if they both fail after 1000Hrs then which would be perceived by the average consumer to have the best quality or have delivered the best return for the investment made ?

As for test reports, like others have already mentioned, I have no real interest, not because I'm not technically minded, but because it's pretty much irrelevant for the application in my environment ... my sourcing decisions have been made, the product has been purchased for the majority of applications I have and even anticipating a number of premature failures (remember MTB means average!) isn't going to keep me awake at night as there are spares available both in a cupboard and at nearby suppliers ..

"now we have TM-30, which gives far more information and accuracy" ... which is great, but changing the measurement or methodology is really of what use to the consumer without a specific technical requirement even if it leads to a technically superior product for specific applications? ... whether I measure my finger in cm or inches it's still the same length, the accuracy simply derives from what I choose to measure it with. If equivalent calibrated equipment is used then my finger could be measured with incredible accuracy, but what's the point when a ruler or tape measure provides a perfectly acceptable answer ...

Time for a coffee ... :coffee:
Z