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Color shift at distance?

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August 16, 2021, 09:49 PM
rburg
Color shift at distance?
Anyone here ever heard of it? I live maybe 1/2 mile away from a bridge. In the center there are 2 (I don't know why) green navigation lights in the center of the bridge. Sitting here in my recliner, both look green. But with binoculars, one is clearly green and the other looks more blue. Anyone got a clue?


Unhappy ammo seeker
August 16, 2021, 09:52 PM
LS1 GTO
Close your eye with the green light. When the color shifted light is back in view (Wink), what color is it?






Life moves pretty fast. If you don't stop and look around once in a while, you could miss it.



"If dogs don't go to Heaven, I want to go where they go" Will Rogers

The definition of the words we used, carry a meaning of their own...



August 16, 2021, 10:02 PM
sigmonkey
Does either light smell like burnt toast?




"the meaning of life, is to give life meaning" Ani Yehudi אני יהודי Le'olam lo shuv לעולם לא שוב!
August 16, 2021, 10:05 PM
parabellum
That should happen only when your space ship nears the speed of light.

All I can say is, a recliner in your space craft sounds like a damn good idea. You want to be comfy when you're haulin' ass between solar systems.
August 16, 2021, 10:10 PM
VBVAGUY
I am guessing weather, temperature, and atmospheric conditions can affect the colors one may see when viewing from a distance. God Bless Smile


"Always legally conceal carry. At the right place and time, one person can make a positive difference."
August 16, 2021, 10:21 PM
sig2392
A color shift has been known to happen when switching from an incandescent to LED bulb.

The color shift is caused by the difference in the bulb color.

Sounds like the incandescent bulb is more yellow than the blue white led bulb.

Just a guess but possible explanation.
August 16, 2021, 10:24 PM
LS1 GTO
Einstein's Rule Number 1: When going faster than the impossible speed of light, how can we be guilty of things in the past which were not illegal anywhere before we arrived here?






Life moves pretty fast. If you don't stop and look around once in a while, you could miss it.



"If dogs don't go to Heaven, I want to go where they go" Will Rogers

The definition of the words we used, carry a meaning of their own...



August 17, 2021, 03:35 AM
kkina
Not an optics expert, but I'm wondering if the color difference is due to "chromatic aberration". It's caused by different colors having different focal lengths, and something that increases with magnification.



ACCU-STRUT FOR MINI-14
"Pen & Sword as one."
August 17, 2021, 06:47 AM
Pipe Smoker
I’ve seen a similar effect. Mercury vapor street lights that appear green-ish in the distance, but changing to blue-ish as I draw nearer. (Or vice versa – don’t remember for sure.) I attributed it to atmospheric color filtering.



Don’t argue with fools.
August 17, 2021, 06:57 AM
Skins2881
quote:
Originally posted by Pipe Smoker:
I’ve seen a similar effect. Mercury vapor street lights that appear green-ish in the distance, but changing to blue-ish as I draw nearer. (Or vice versa – don’t remember for sure.) I attributed it to atmospheric color filtering.


With MH and HPS lamps they change colors as they warm up usually blue or green then white/yellow once warm depending on bulb type and characteristics. They also change color with age, and when lamps/ballasts start to fail but haven't completely died.

If not for the binoculars I would say it's due to mercury vapor lamps.



Jesse

Sic Semper Tyrannis
August 17, 2021, 08:59 AM
cas
Maybe not related to what you're talking about, but being "colorblind"it happens to me frequently, and at nowhere near the distances you're talking about.


_____________________________________________________
Sliced bread, the greatest thing since the 1911.

August 17, 2021, 09:08 AM
snwghst
You sure it’s blue?

If Nav lights they should be red and green


-------------------------------------------------------------------------------------------
Live today as if it may be your last and learn today as if you will live forever
August 17, 2021, 02:25 PM
GGF
I know exactly why you're seeing that.

You've been into that case of Buffalo Springfield (or whatever it's called ) whiskey you got stashed!

Dick stay out of that or you'll be trying to sharpen that set of Randall steak knives next!
August 17, 2021, 02:40 PM
CPD SIG
quote:
Originally posted by snwghst:
You sure it’s blue?

If Nav lights they should be red and green


This^^^

"Red Right Returning - Red and Green stay in between"
(Oh, that was a loooonnnnggg night on a boat with a drunk chick. Roll Eyes)
Unless you're at an angle and catching the light from the side of the filter, or the filter came off/glass broken.

If it's blueish, it's probably an LED light, some of those have a blueish tint.


______________________________________________________________________
"When its time to shoot, shoot. Dont talk!"

“What the government is good at is collecting taxes, taking away your freedoms and killing people. It’s not good at much else.” —Author Tom Clancy
August 17, 2021, 03:23 PM
bronicabill
My first thought was chromatic aberration from the lenses in the binoculars. Just my opinion...


____________________________
Bill R.
North Alabama

_____________________________
I just can't quit grinnin' from all of this winnin'!
August 17, 2021, 05:21 PM
0-0
Wind speed, please? Wink

0-0


"OP is a troll" - Flashlightboy, 12/18/20
August 17, 2021, 07:15 PM
bald1
Last time I squinted and asked a question about color of a distant object, my smartass son told me to quit clenching so hard as it affects the blood flow to my head. And to just go ahead and pass gas and pray that it was limited to just that. Big Grin



Certifiable member of the gun toting, septuagenarian, bucket list workin', crazed retiree, bald is beautiful club!
USN (RET), COTEP #192
August 17, 2021, 08:58 PM
feersum dreadnaught
It’s th3 Doppler effect. On the Coriolis force. Maybe a Bose-Einstein condensate.



NRA Life Member - "Fear God and Dreadnaught"
August 18, 2021, 12:56 AM
Skull Leader
I was out on patrol several years ago and saw flashing red and blues a couple miles up the road. Raced there to back up the LEO and never found them. Was a shift like you are talking about. Blew my mind at the time. I still see the same flashing some nights in the same spot. It's very weird.
August 18, 2021, 04:02 AM
sybo
You have been playing that Psychedelic music again aren’t you Bob……. Wink