Benches: Stay or go?

BY JANE PRENDERGAST | CINCINNATI ENQUIRER

July 19, 2007

 

PHOTO: Sleana Penn, from Price Hill, waits for a bus on a street bench at the corner of 8th Street and State Street in Lower Price Hill.

THE ENQUIRER / LEIGH TAYLOR

 

CINCINNATI - The advertising benches along Cincinnati streets might be eye-catching, but some also are illegal and could soon be removed.

 

New rules this month impose stricter guidelines for advertising benches and allow the city to remove any that violate City Council criteria...

Those 1960's benches should go!

I noticed that they changed the streetlights on Central Parkway to LEDs.  I like LED light a lot, but I much prefer the old ball shaped fixtures to these new paddles.  What do you all think?

 

 

 

Yeah the light will be better but the fixtures aren't as nice.

 

Is there any official info on changing to LEDs citywide? I've noticed it in quite a few places recently and it's so much nicer. That orange glow of old cannot be sent to the past fast enough. It makes a nice area look like trash.

Trouble is most of these new LEDs have a color temperature of 6000K which is really too blue. I've seen some cobrahead retrofits in Deer Park and Silverton that look super dreary and really no better than the mercury vapor lights of 30+ years ago. The pendulum is swinging too far in the other direction if you ask me, even though the blue LEDs have a better color rendering index than the high pressure sodium lights they're replacing, which can basically only render orange and little else.

 

Incandescent lights for reference are 2800K while the high pressure sodium is 2000 to 2200K.  While these new lights don't need to be as yellow as an incandescent or halogen light, they should really be no more blue than say 3500 or maybe 4000K. The reason we're in this conundrum is that the blue LEDs are the new technology that allowed them to be made so bright in the first place. Adding phosphors to warm up the light reduces efficiency, and these high output lights are only twice as efficient as their high pressure sodium and metal halide counterparts to begin with. LED traffic signals on the other hand are more than 10 times as energy efficient than the ones they replace.

Trouble is most of these new LEDs have a color temperature of 6000K which is really too blue. I've seen some cobrahead retrofits in Deer Park and Silverton that look super dreary and really no better than the mercury vapor lights of 30+ years ago. The pendulum is swinging too far in the other direction if you ask me, even though the blue LEDs have a better color rendering index than the high pressure sodium lights they're replacing, which can basically only render orange and little else.

 

Incandescent lights for reference are 2800K while the high pressure sodium is 2000 to 2200K.  While these new lights don't need to be as yellow as an incandescent or halogen light, they should really be no more blue than say 3500 or maybe 4000K. The reason we're in this conundrum is that the blue LEDs are the new technology that allowed them to be made so bright in the first place. Adding phosphors to warm up the light reduces efficiency, and these high output lights are only twice as efficient as their high pressure sodium and metal halide counterparts to begin with. LED traffic signals on the other hand are more than 10 times as energy efficient than the ones they replace.

 

When you say 'too blue', you really do need to qualify it. IMO, it seems bright white, which can be a stark color, but generally blue hues make things look pretty good. From ones of seem, it makes the urban environment seem more clean, while the older yellow/orange hued lights made things look old and dingey.

I qualified it with everything else I wrote Rob.  Even sunlight at the height of noon is around 5500 to 6500K, BUT humans are more sensitive to blue light at lower luminance (brightness) levels.  http://en.wikipedia.org/wiki/Kruithof_curve  So the same color temperature looks more blue to us when it's darker than it does when it's lighter out.  If you've ever put a "daylight" 5500K bulb in a typical indoor fixture, like a table lamp, wall sconce, or recessed can light it looks positively horrible.  It's a harsh blue that really looks nothing like daylight at the low wattage levels used indoors.  It may make things look more cleaner, but in a sterile doctor's office or laboratory kind of way.   

 

In residential applications you're usually specifying 2800K to 3000K lamps and fixtures, while in commercial settings it's more like 3000 to 3500K where things are brighter.  The one exception is usually jewelry stores where they use 4000 to 4500K lighting in their display cases because it makes diamonds look clearer and more sparkly.  These outdoor street lights are similar to indoor conditions because the surroundings are so dark and our eyes are generally more in their "night mode" with higher sensitivity to blue light.  Humans spent tens or hundreds of thousands of years using fire for lighting, so we have a natural predisposition to prefer the warmish light that incandescents produce.  It doesn't mean that the piss-orange of high pressure sodium is better, just that these super cold LEDs are fixing one problem by going to far in the other direction. 

I qualified it with everything else I wrote Rob.  Even sunlight at the height of noon is around 5500 to 6500K, BUT humans are more sensitive to blue light at lower luminance (brightness) levels.  http://en.wikipedia.org/wiki/Kruithof_curve  So the same color temperature looks more blue to us when it's darker than it does when it's lighter out.  If you've ever put a "daylight" 5500K bulb in a typical indoor fixture, like a table lamp, wall sconce, or recessed can light it looks positively horrible.  It's a harsh blue that really looks nothing like daylight at the low wattage levels used indoors.  It may make things look more cleaner, but in a sterile doctor's office or laboratory kind of way.   

 

In residential applications you're usually specifying 2800K to 3000K lamps and fixtures, while in commercial settings it's more like 3000 to 3500K where things are brighter.  The one exception is usually jewelry stores where they use 4000 to 4500K lighting in their display cases because it makes diamonds look clearer and more sparkly.  These outdoor street lights are similar to indoor conditions because the surroundings are so dark and our eyes are generally more in their "night mode" with higher sensitivity to blue light.  Humans spent tens or hundreds of thousands of years using fire for lighting, so we have a natural predisposition to prefer the warmish light that incandescents produce.  It doesn't mean that the piss-orange of high pressure sodium is better, just that these super cold LEDs are fixing one problem by going to far in the other direction. 

 

I gotcha and see what you're saying now. I do remember when those new bluish indoor bulbs came out and I got a couple - everything looked blue for awhile until I got used to them. I would guess its the same as those headlights that are super bright and look blue when they are coming at you. The sterile blue/white of the LEDs as outdoor light may not be the best solution then. Until the tech improves... we're stuck?