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andyrdj

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About andyrdj

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    Registered User
  • Birthday 22/10/1974

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  • Location
    Sheffield
  • Interests
    Photography
  • Occupation
    IT Professional
  1. Firstly, it's worth noting that daylight varies from 5600k at mid day to around 2000-3000 at sunrise/sunset. I personally don't think it's good to try to get midday lighting at night because the extra blue light will inevitably disturb sleep cycles and supress our best natural cancer fighting agent - Melatonin. Secondly., the colour temperature is only a nominal one. A true colour "temperature" implies a spectrum equivalent to Black body radiation (i.e. heat produced by a purely thermal effect.). Here are several example black body. distributions for different temperatures http://upload.wikimedia.org/wikipedia/commons/e/e7/Bbs.jpg LED lights do not tend to follow this spectrum well because they are not themal radiation, - they have extra peaks in the blue region and are noticeably deficient in the reds and yellows. Here is another picture showing the distributions of different light sources http://www.energycircle.com/sites/default/files/imagecache/Inline/images/stories/10014/light-spectrum-common-light-sources.png I've seen outdoor incandescent lighting at night and it's noticably different - a lot more comfortable on the eyes. This colour deficit is improving with later LEDs, however - see this link here http://www.soraa.com/news/vivid-launch-home You'll note that in the later version the "blue overshoot" is gone, and the light extends a bit more into the red. I hope that this will lead to a better balance in future versions. The image below shows supression of melatonin by colour http://peperperspective.files.wordpress.com/2012/02/slide11.jpg I recently discovered that colour discrimination ability varies greatly from person to person - so there will be a lot of people at the lower end of colour sensitivity who won't notice the difference. Some people, for example, look at a forest and just see green, others see a whole rich range of colours. At the extreme end, there are people who are very sensitive to fluorescent and even some LED lights, as shown here http://www.spectrumalliance.co.uk/ I personally think that getting away from the old sodium is good, but where we're going is very pale and lifeless. Just a little more red and yellow, and a little less blue, would suit me. The idea of the whole city at night looking like the cheap lighting on a bus is very depressing to me. Lastly, the new lighting is definitely too intrusive off the roads. This year I've seen windows with christmas decorations which used to look lovely, but are now drowned out by the intrusive street lighting. It's not just terraced houses that look onto the street, it's houses in their own gardens over 10 metres from the road which are still bathed in this all pervasive blue light. So this might be the last year you get to enjoy christmas lights before they're rendered ineffective by the near daylight level of light. Certainly some of the displays in the middle of roundabouts willl be lost. Also, say goodbye to the enjoying the lovely winter constellations in the city. I recently tried this on the same night in a street with sodium lamps, then just down the road with the new LED lamps. With the sodium lamps, I could quite easily make out Orion and the Pleiades. With the LED lamps I couldn't see any more than the brightest couple of stars. It's an interesting truth that the sides of your eyes are more sensitive than the front to light (more rod cells, fewer cone cells) so light interference can actaully be greater from lights you're not directly looking at. It doesn't have to be this way - at the very least we should expect shielding and/or reflectors to concentrate the light onto the streets. I know people with rooms right next to the large lights who say it's like daylight at night without a thick blackout curtain. The council should be ashamed for carrying this out so crassly and insensitively. ---------- Post added 18-12-2013 at 16:52 ---------- It seems a strange attitude to take, that our city should not look pleasing to the eye. I wonder if the same thinking is behind much of the horrible architecture we have to ensure. And I've met lots of people who think the new lights look horrible. ---------- Post added 18-12-2013 at 16:55 ---------- I beleive they do have a legal obligation to shield it from you if it's causing a nuisance - I've read about it happening in other councils. In some cases it's jsut been a bloke with some masking tape, but hey, it's a start. Unfortunately their response is typical of everything I've seen about the council with this - they don't give a monkeys about individuals, just the plans as a whole. They abdicate all repsonsibility ---------- Post added 18-12-2013 at 16:57 ---------- Are you the sort of person who doesn't like nice warm lighting in his house at night, then? The sort who has a pale fluorescent lamp in the sitting room? ---------- Post added 18-12-2013 at 16:59 ---------- He shouldn't have to. There's a benefit to having the light change gradually and naturally in the mornings, it wakes people up gently and helps set their body clock. It's funamentally unfair to have to pay to put the council's crass mistakers right. ---------- Post added 18-12-2013 at 17:08 ---------- A good link here about light pollution misconceptions http://www.britastro.org/dark-skies/misconceptions.html?0B#newlights "Unfortunately, new streetlights can often cause more light pollution than the older lights they replace! Light pollution is not solely caused by the old Low Pressure Sodium lights. Mathematical modelling shows that the main cause of light pollution is from light emitted at or just above the horizontal (mostly in the first few degrees). Modern high pressure sodium luminaires often have bowl-shaped lamps, or are tilted by up by 5° - both result in light being emitted a few degrees above the horizontal, and so both contribute significantly to light pollution. " Below that is a set of images showing how shielding can work.
  2. I have written the following on the Sheffield Lib Dem's board. I urge people to digest the information available and consider acting on it --------------------------------------- I appreciate the reasoning behind the LED street lamps change, but it has been disappointing to see the bad decisions that have been made with what could have been a Golden opportunity for improvement. I list my reasons for thinking this below. - The lights are simply too bright in places - night should not be as bright as day for n24 hours, it's bad for the psychology -The spectrum of light has been poorly chosen - although the old Sodium lamps were far too yellow, this is far too blue. - Numerous research suggests that bright blue light interferes with melatonin production and affects the body clock. It also removes one of the body's major defences against cancer. Further research suggests that bright blue peaks in the spectrum damages the retina. - It's been ok having some blue light and some yellow light, but when it's all blue it will make the town look like a morgue. Very depressing. - The shielding on these lights is very poor, more light seems to escape sideways than with the old Sodium lamps. It completely ruins any chance of enjoying the Night sky. It also means that people living near the lamps have ridiculously bright light pouring into their bedrooms. I'm very disappointed in the council for being so thoughtless and insensitive with how they made these improvements - it could have been so much better. I therefore suggest the following improvements, which hopefully can be made in the near future. 1. Not so bright later on at night please - dimming after rush hour would be good. 2. Consider replacing the soulless blue lights with something a bit more like the spectrum of an old incandescent bulb - not the old sodium yellow, but a little bit warmer. LEDs with theist characteristic are beginning to be developed. 3. Shield the sides of the lamps so that it reflects only onto the street, and not into people's houses and gardens. I am going to be busy raising awareness of these issues, so I hope the council can be proactive and act before the public's dislike causes embarrassment.
  3. happycoziam seems to be either relentlessly jolly or is enacting a bit of subtle sarcasm in their post. Seriously, to be pleased because the light from the street invades your house? In a nice relaxing living room the lights really need to be a warm yellow at night. I've been in people's houses where it was just a bright unshaded energy saving bulb and it's a bit horrible. But that aside, there is quantitative evidence available to suggest that this will be bad for your health. Google "Limiting the impact of light pollution on human health, environment and stellar visibility" "Migration from the now widely used sodium lamps to white lamps (MH and LEDs) would produce an increase of pollution in the scotopic and melatonin suppression bands of more than five times the present levels, supposing the same photopic installed flux. This increase will exacerbate known and possible unknown effects of light pollution on human health, environment and on visual perception of the Universe by humans. We present quantitative criteria to evaluate the lamps based on their spectral emissions and we suggest regulatory limits for future lighting." In other words, your sleep regulating and cancer suppressing hormone will itself be suppressed by a factor of 5 compared to the current situation. And that's without taking into account the increased intensity. And the disruption to the life cycles of nocturnal animals could be huge. It's one thing when it's just the main roads, but when every side street is brighter than your front room, bright enough to cast shadows more intense than on the brightest moonlit night? Also google "LED streetlights yanked for alleged brain damage risk" On the smartplanet wesbite, the story reads "This is new to me: LED streetlights can allegedly damage people’s brains. So says one person from the north of England, and his claims were persuasive enough to convince the city of Trafford to suspend plans for replacing 26,000 conventional streetlights with LED lamps." Although this story is badly reported, one of the links in the discussion on this page points to a better explanation (google led4light node 29 and you will see the following "A more accurate description would be that LED street lights could disrupt our Circadian Rythms or interfere with our sleep/wake hormone production. Add to this the fact that poor fixture head design will create light pollution which allows the light to spill everywhere (including your bedroom window) and you have a recipe for some very disgruntled residents who blame the new LED technology, rather than better designed use of it. This same problem by the way is not confined to the UK many states in the US are having similar problems with dire financial consequences for local state authorities who have also been seduced by the promise of much lower electricity bills. It is costing more to put things right than the promised savings.LED technology is definitely the way to go for our lighting needs but not all LED products are the same!" So our council blindly carries on despite the fact that councils elsewhere have recognized the danger. Folks, please realise that it isn't an "either-or" for the crappy old sodium streetlamps or the blindingly bright new ones. It is possible to get LED lights that have a slightly warmer spectrum than this horrible blue one, and it is also possible to turn down the intensity a little to allow people some privacy. When it invades your house to the extent that you need blackout blinds to sleep, it's just not on.
  4. Difficult to describe, and I did choose my words poorly. I suppose the old sodium lamps were low down, so even with the sideways leakage it wasn't so bright. These are higher up and brighter, and it seems to me that you get more of the main beam straight at your eyes. Unpleasant. ---------- Post added 08-03-2013 at 20:05 ---------- Yes, and who really wants that 24x7? ---------- Post added 08-03-2013 at 20:11 ---------- I wasn't using the Daily mail as my source. I know it's got a lot of claptrap, but you can't assume everything the Mail says is exactly wrong. I need to make a few more posts before this forum iwll allow me to do links, but I will dig out the sources Google "melatonin cancer pubmed" and "melatonin blue light" ---------- Post added 08-03-2013 at 20:12 ---------- Still getting posts up...
  5. I don't think they will - the issue is not so much the frequency spectrum of sodium lamps as their design which shone light sideways into people's eyes, instead of down on the street. These lights will be brighter and higher so the situation will be worse. ---------- Post added 08-03-2013 at 19:22 ---------- Just a reflective conical guard around the light, really, to stop light going sideways and direct it down on the road.
  6. I have to say at first glance I really, really dislike these lamps, I hope it won't be too bad in the long run but fear it will be awful . I can see the arguments for energy saving, but I have several criticisms: 1. The light effect they're chosen makes everything look harsh like a morgue. I know sodium lamps aren't ideal, but at least the yellow colour gave a bit of gentle softness that is appropriate for the night. We surely don't want the night to be as bright as the day 24x7 - do we? Blue frequencies of light disturb sleep and influence Melatonin production. If you want to settle down at night, it's a well established medical fact that you need yellows and Reds - blue decreases Melatonin. And failure to get enough Melatonin means that you lose its cancer suppressing effects. This street lighting could mess up your sleep patters and really make you ill! 2. The lamps are positioned very high up. This means that the glare hits you in the eyes wherever you go. 3. Will they end up going down the side roads? Will these tall lamps even shine brightly into people's back gardens. 4. As a keen amateur astronomer I wonder if I'll ever have the pleasure of seeing a dark winter's night from my back garden ever again. At present my front garden faces south and I can see Orion in the winter. Scrub that forever if they put one of those lights in the street. I'd like to see the following: 1. A slightly softer, yellower shade of LED - they do exist! 2. Lamps positioned lower and with guards around - so that the light is reflected into the street, not sideways into people's eyes. 3. Perhaps reduce the brightness.
  7. Looking to hire a pub or function room somewhere for a party around 9-10 august Would like somewhere with either an existing sound system, or a license so we can bring our own and mix some lively tunes (we're all DJs). Any ideas would be welcome, cheers:thumbsup:
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