Saturday, December 20, 2014

LA Street-Light Colors


LA Streetlights, before (left half) and after (right half)
c/o LA Curbed and LA Bureau of Street Lighting
Los Angeles is in the midst of a major street light replacement program. They are changing out the sodium vapor lights (left) and replacing them with LED lights (right).

They're making the change because the new LED lights run far more efficiently and last longer. But an additional consequence of the change is a different visual appearance to nightscapes, which affects nocturnal on-the-spot painters, filmmakers, or anyone who is sensitive to the qualities of light.

LA Streetlights, before (left half) and after (right half) c/o LA Curbed
The most obvious difference is that the light has an overall cooler appearance compared to the distinctly orange colored sodium vapor lights, which are the most common street lights these days.

That older sodium vapor light is almost a monochromatic orange, as you can see from the solitary spike on the spectral power distribution chart at the lower left, which charts wavelength against output.

Spectral Power Distribution of various light sources c/o NoFilmSchool
Even the improved high pressure sodium lamps (bottom center) are still not very good on reds or blues. Incandescent light (upper left) is warm, but it contains some of all the wavelengths, which means you can correct it with a colored gel. Metal halide (lower right) is a whitish street light that's used in a lot of big-box parking lots.

Natural daylight (center top) is the standard, with all the colors well represented.
Spectral Power Distribution for a Philips Lumileds LED
Here's a chart for an LED light, but it's not one of the street-light LEDs that they're using in LA. LEDs can vary quite a lot in the quality of light they deliver, but the bottom line is that the light will be cooler and more natural than the creepy-zombie effect of sodium vapor lights. 

It's also good news because the best best portable work lights for outdoor painters are the small LED lights, and the more you can match your work light to the subject's light, the more likely you'll choose the right colors for the painting.
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More in my book about light and color for painters:
Color and Light: A Guide for the Realist Painter
Read more online:
No Film School: "Why Hollywood Will Never Look the Same Again"
LA's New LED Streetlights Will Change the Way Movies Look
Thanks, Angela

10 comments:

KM Ryan said...

I'm sure the new lights will look more natural, but it's bad news for astronomers. It's possible to filter out one or a few frequencies of light pollution, but not a full spectrum.

David J Teter said...

Yes, I have been watching them get replaced.
It is odd when half a street or the next block over is a different color as you drive around, for now.
I can still remember when the lights were that cool green years ago.

Marian B said...

It is also claimed that the newer lights are 'safer' because they look more like natural lighting. Who knows.

krystal said...

One of my filmmaker friends didn't quite like the new ones; he says the lack the 'character' that the old ones had, which I guess is something a filmmaker would have to add on their own stylistically (by using...street lights from a lighting rental house or lights they own dun dun!) Those have become immensely popular, btw (filmmakers adding HPS(high pressure sodiums) and MH (Metal Halide) or MV(Mercury Vapours) to their shoots to get the cool/warm effect; a certain DP, Shane Hurlburt, LOVES to use those and he does a great job with them.
Also, there is that wonderful flicker issue (if it is pwm) which I"m interested to find out about, esp as everyone is using digital/CMOS cameras these days. Oh well....
Also, depending on the binning, would be interesting to see them decay over time (they won't all just turn at the same time, obviously). And of course, LEDs are quite deceptive in lumens (because they're not full spectrum source and the values can read quite differently depending on the type of metre, etc). Mike Wood has done a lot of articles on this stuff, so it would be interesting to see over time how true this stuff all is. LEDs haven't been around that long to see if that "they last longer" claim is true as yet (their biggest issue is cooling because there is a LOT of heat generated by the electronics, which powers the LEDs)

Gavin said...

Imagine how antiquated city nightscape paintings and photographs are going to look to future generations. Maybe they will be looked back on with a sense of nostalgia.
I like the soft, warm street lighting; it softens the transition from day into night. The LEDs are too cool, too 'daylight' - it would take me a long time to adjust. Fortunately they're not being installed where I live at present.

Rich said...

On a next night-flight, looking down on the city-lights from the window, I'll have a lookout for this.

Rondodog said...

Another interesting effect of the new LED lights: new diffraction light spots in the shadows, particularly when LED street lights filter through the leaves of trees. The lights on my street create a "waffle" shaped light spot(s) when the main light (usually made up of several-to-many individual LED's) is filtered through the trees. Gives the sidewalks an alien, almost a "Tron" kind of look.

cashwiley.com said...

I really enjoy this topic, it's an interesting extension of the topic from Color & Light.

I've wondered how much my lighting choices affect my painting. I favor warm lighting in my house and my primary painting light is a warm CFL...and I tend to favor warm colors when I paint. I wonder if that's my natural inclination to that portion of the spectrum or if the cooler stuff just looks off under the lights so I stay away from it?

Speaking of streetlights, are you familiar with Jeremy Mann? Some really nice work on his FB page - https://www.facebook.com/JeremyMannART

Tijmen Brozius said...

This is basically a health disaster - blue light keeps people from getting good sleep, because it stops the body from producing melatonin.

There are apps like justgetflux.com or Twilight that solve this problem in digital screens, but when your whole city is lit in bluish light, there is aother solution:

Blue-blocking glasses. I wear them when it gets dark outside, and it really reduces the stress on the eyes from bright train lights and street lights, and makes it much easier to 'switch off' before I go to bed.

Barry Bridgeford said...

I enjoy bird-watching at my bird-feeders. Where will the birds roost and sleep when the LCD street lights flood the neighborhoods with high levels of daylight wavelengths through the night?