kabsonline
Best SSL Train: S Stock Best Tube Train: 92 Stock
Posts: 686
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Post by kabsonline on Feb 16, 2015 21:52:26 GMT
Hi All
Just wondering if anybody else had noticed the new blue tinted lightbulbs being put on the S Stock recently? I think they are only being replaced as one breaks but not liking them. The yellow tinted bulbs at the moment give the interior of the train a less intrusive feel while the new ones are very similar to that on the A Stock. Is it a permanent change? I can't see them being pleasant if the whole train gets them!
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metman
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5056 05/12/1961-23/04/2012 RIP
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Post by metman on Feb 16, 2015 22:04:34 GMT
I quite liked the A stock bulbs they were a cleaner light. The S stock strips appear very yellow to me - much like dirty teeth! It's shame a warmer white couldn't be found unless the interior of the S stock is the cause.....
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Post by Hassaan on Feb 17, 2015 0:44:04 GMT
The yellow-looking tubes are a "warm white" colour (temperature 3000K, denoted as 830 on the tubes) and the closely related 2700K is what you'll find with most CFL energy saving bulbs used everywhere. This colour of tubes has also been used in the various Siemens Desiro classes. At the opposite end is "daylight white" with a colour temperature of 6500K (shown as 865 on the tubes), which gives a very harsh blue tinge if you are not used to it but is actually close to that of bright sunlight. However, the replacement tubes I have seen are in the middle of this range, at 4000K (shown as 840) or "cool white". This is the colour used in the A, C and D stocks, although replacements in the C stock in recent times were of the warmer colour. They will look a bit blue next to the yellow of warm white. The easiest way to work out which is used is to look at what is written on the tube itself!  Cool-White and Warm-White T5 fluorescent tubes by hassaanhc, on Flickr |
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Post by suncloud on Feb 17, 2015 14:27:39 GMT
2700K being close to typical colour temperature of filament lamps, and is favoured for the kind of lamps used in 'domestic' fittings. For some of the more 'commercial' lamp types getting colour temperature of 2700K can prove difficult. 'Cooler'/Bluer colour temps are better for workplaces. (Up to a point).
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class411
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Post by class411 on Feb 17, 2015 14:53:59 GMT
I think I may have mentioned it before on this site, but I remember several years ago I started noticing one or more D-Stock carriages with unusual lighting. It was clearly a 'daylight' type of tube but had the odd effect of making the inside of the carriage seem brighter than daylight itself, even on a sunny day, if the train was in the shade.
Obviously it's not at all unusual to see a train brighter that its environment, but doing so when you were not underground and could see blue sky and sun in a different part of your field of vision was odd, As I remember, the D stock did get cooler, brighter lighting, but not to the same extent as what must have been a couple of test vehicles.
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Deleted
Deleted Member
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Post by Deleted on Feb 17, 2015 19:56:02 GMT
Why is this being done? One of the features that I actually like about the S stock and they change it!
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Post by crusty54 on Feb 17, 2015 20:48:25 GMT
If they are LED tubes they may just be faulty.
Power surges can affect them.
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Post by Hassaan on Feb 17, 2015 23:33:22 GMT
If they are LED tubes they may just be faulty. Power surges can affect them. No not LEDs, just standard fluorescent tubes (in the latest and most energy efficient T5 versions, compared to the older T8 and T12) |
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Deleted
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Post by Deleted on Feb 17, 2015 23:36:21 GMT
If they are LED tubes they may just be faulty. Power surges can affect them. I doubt it LED's are low voltage devices and are more robust than the filament bulbs they replaced! "White" LED's tend to have a blue tinge to them as well |
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class411
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Post by class411 on Feb 18, 2015 9:05:58 GMT
If they are LED tubes they may just be faulty. Power surges can affect them. An LED cannot change colour. The colour is fundamental to the materials used. (Similarly, sodium and mercury lamps cannot change colour.) If they are LED tubes they may just be faulty. Power surges can affect them. I doubt it LED's are low voltage devices and are more robust than the filament bulbs they replaced! "White" LED's tend to have a blue tinge to them as well 'White' LED's can be many shades of white depending on the method used to generate white - either mixing RGB, or using blue or UV with a fluorescent coating. At home I have warm wihte LED lighting in all rooms except the kitchen which is 'daylight' |
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Post by crusty54 on Feb 18, 2015 9:23:31 GMT
The white is made up of 3 colours and when one colour fails the tone of white changes and a blueness is one example of this.
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Post by domh245 on Feb 18, 2015 9:54:23 GMT
The LED headlights and door lights on the S stock do have a definite blue tinge, I am assuming this is because the LEDs are specified as such, and not because of a uniform failure of 1 colour in every LED used in the project .
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North End
Beneath Newington Causeway
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Post by North End on Feb 18, 2015 10:38:35 GMT
If they are LED tubes they may just be faulty. Power surges can affect them. An LED cannot change colour. The colour is fundamental to the materials used. (Similarly, sodium and mercury lamps cannot change colour.) I doubt it LED's are low voltage devices and are more robust than the filament bulbs they replaced! "White" LED's tend to have a blue tinge to them as well 'White' LED's can be many shades of white depending on the method used to generate white - either mixing RGB, or using blue or UV with a fluorescent coating. At home I have warm wihte LED lighting in all rooms except the kitchen which is 'daylight' I must say I totally despair at how in the last couple of years the simple subject of train lighting has become such a 'fad' that virtually every type of train now seems to have a different type or colour of lighting, including some wholly ghastly and vile designs which appear blue or "daylight". Last year I rode on 205032 on the Dartmoor Railway, which still retains what appear to be the same flourescant tubes as on the day it was withdrawn, so nice just to have a train with 'normal' lighting, not too bright, and no silly colours. Felt like I was 10 years younger again. For what it's worth, my home remains very nearly 100% tungsten, and will be for many years to come! :-) |
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Post by trt on Feb 18, 2015 11:30:00 GMT
Personally, I dislike the white LED lighting used on roads nowadays. It's far too similar to car headlights and gives the impression that you're going to meet another vehicle round the bend when you see it reflected off door panels etc.
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North End
Beneath Newington Causeway
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Post by North End on Feb 18, 2015 11:40:07 GMT
Personally, I dislike the white LED lighting used on roads nowadays. It's far too similar to car headlights and gives the impression that you're going to meet another vehicle round the bend when you see it reflected off door panels etc. Agreed 100%. I'm not sure if some of the LED street lighting is deliberately dimmer than what it replaced, however I find it doesn't light up the road nearly as well. My car retains conventional headlights, and I'm very glad it does. As an aside I also find some of the fittings highly unattractive in appearance, but obviously this is my personal view. |
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Post by trt on Feb 18, 2015 14:13:01 GMT
Personally, I dislike the white LED lighting used on roads nowadays. It's far too similar to car headlights and gives the impression that you're going to meet another vehicle round the bend when you see it reflected off door panels etc. Agreed 100%. I'm not sure if some of the LED street lighting is deliberately dimmer than what it replaced, however I find it doesn't light up the road nearly as well. My car retains conventional headlights, and I'm very glad it does. As an aside I also find some of the fittings highly unattractive in appearance, but obviously this is my personal view. Oh I agree. When you compare the modern to, say, some of Lady Wulfrun's photographs of lights from railway stations and bus depots... www.flickr.com/search/?w=8050359@N07&q=lampThere's just no elegance anymore. |
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class411
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Post by class411 on Feb 18, 2015 15:55:03 GMT
The white is made up of 3 colours and when one colour fails the tone of white changes and a blueness is one example of this. 'fraid not. If green failed, you would get magenta, not blue tinged white. If red failed you would et cyan, not blue tinged white. If you were generating white light by having a large number of R, G, and B lamps, failure of a number of lamps, even if all the same colour, would result in a blotchy appearance, not a blue tinged white. |
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Post by crusty54 on Feb 18, 2015 16:37:31 GMT
The white is made up of 3 colours and when one colour fails the tone of white changes and a blueness is one example of this. 'fraid not. If green failed, you would get magenta, not blue tinged white. If red failed you would et cyan, not blue tinged white. If you were generating white light by having a large number of R, G, and B lamps, failure of a number of lamps, even if all the same colour, would result in a blotchy appearance, not a blue tinged white. 'fraid yes Happened to a dozen or so lamps at Baker Street. They developed a very blue tint. Not suggesting a complete colour fail happened. |
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class411
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Post by class411 on Feb 18, 2015 18:35:07 GMT
'fraid not. If green failed, you would get magenta, not blue tinged white. If red failed you would et cyan, not blue tinged white. If you were generating white light by having a large number of R, G, and B lamps, failure of a number of lamps, even if all the same colour, would result in a blotchy appearance, not a blue tinged white. 'fraid yes Happened to a dozen or so lamps at Baker Street. They developed a very blue tint. Not suggesting a complete colour fail happened. Mmm, I can see how that could happen, as humans are very bad at identifying colours (actually it's because we are uncannily good at adjusting for the changing colour of sunlight [which also spills over into adjusting for all sorts of tints of artificial light], according to the time of day/year, vital to quickly detect danger and food), so a cyan cast might appear blue, particularly if the green component is quite blue to start with - something I have noticed in quite a few LED's. |
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metman
Global Moderator
5056 05/12/1961-23/04/2012 RIP
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Post by metman on Feb 18, 2015 20:16:42 GMT
I was under the impression that the S stock had xenon headlights or are these LEDs?
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Post by trt on Feb 19, 2015 9:50:00 GMT
'fraid yes Happened to a dozen or so lamps at Baker Street. They developed a very blue tint. Not suggesting a complete colour fail happened. Mmm, I can see how that could happen, as humans are very bad at identifying colours (actually it's because we are uncannily good at adjusting for the changing colour of sunlight [which also spills over into adjusting for all sorts of tints of artificial light], according to the time of day/year, vital to quickly detect danger and food), so a cyan cast might appear blue, particularly if the green component is quite blue to start with - something I have noticed in quite a few LED's. You'd be talking there about the phenomenon of colour constancy and the retinex theory of Edwin Land (of Polaroid). I spent a great many years working in that field! |
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Post by suncloud on Feb 19, 2015 19:46:17 GMT
Development in lighting technology is moving very fast, especially in LED products. Manufacturers in my industry are having to limit newer brighter LED chipsets to match those they used when developing their products.
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Post by trt on Feb 20, 2015 9:29:08 GMT
Don't worry. We'll run out of indium before long.
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Post by norbitonflyer on Feb 20, 2015 20:26:28 GMT
I must say I totally despair at how in the last couple of years the simple subject of train lighting has become such a 'fad' that virtually every type of train now seems to have a different type or colour of lighting, including some wholly ghastly and vile designs which appear blue or "daylight". Not just every train, but even within a train. Seeing a Great Western IC125 from a distance last night, it was strikingly noticeable that the two carriages at the London (1st class) end had a much more orange tinge to the lighting than the others did. |
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