Effects of Fog?

I don't think this is going to be an easy question to answer. I don't expect anybody to write an encyclopedia, I'm looking for information, articles, and resources, that I can read on my own, to try and understand.

Every so often, I have to go drive around my workplace and make sure none of the pole fuses on the 13,200 line have opened. Life being the way it is, there is usually some kind of water falling from the sky.

I'm looking for a way to assess the effects of fog/snow/rain on light, so that when I look at a flashlight, I have some idea of how badly the beam is going to attenuate on it's way up to that pole fuse. Any help is appreciated.

I would recommend a thrower, not a flooder. The flood effect will bounce reflected light off the fog and blind you. Also, lower color temperature like 3,000 Kelvin will seem to penetrate fog better than cooler color lights.

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I agree with MAD777. I have done work where I need to be able to see a distance in fog and have found tightly focused beams to get there more effectively than flood lights. Although I can also say that enough brightness can sometimes overcome the beam focus. Though usually the glare created blows out any sort of night vision. However I have not found the color to make any real difference except maybe more as a perception thing. I specifically tried a Wowtac A1S in both warm white and cool white and the only thing I could say definitively was that the warm white wasn't as bright. I guess maybe that it was softer on the eyes so it didn't feel as though it was glaring as much.

Sorry I don't really have any links to anything for you to read yourself.

We have a natural tendency to hold the flashlight near our eyes. It just makes sense. But in fog or high humidity to hold the light over your head or at your waste actually makes a big difference. Now looking up at wires would mean it would probably be best to hold the light with a raised arm. Looking at a ground mounted power box for example it would be better to hold it waste high.

A warmer tint will not cause the millions of droplets to appear so bright. Something in the neutral range will give you that added appearance of a cool beam while cutting back on how brightly lit the droplets appear. Warm is great but it does not cue the brain of details of a given object at the distance as quickly as a cool beam does even though both may be lit about the same. Elzetta lights have and Malkoff offers a beam in the mid 4000 kelvin family for just that reason.

And as others mentioned, a thrower beam is best. Look for candela numbers to get a clue. Example would be a Maglite ML25 only has just under 200 lumens but has a candella number over 25000. The new 2D classic has a rated 213 lumens and 53000 candella. The 2aa minimag is rated at 332 lumens but says it has a mere 7399 candela.

To go into the weeds a bit, the size and shape of the LED itself and the method light leaves the light either by reflector shape or a lens that magnifies the beam called total internal reflection (TIR) make the difference in how those light photons travel.

So if you have a brand you like such as a Fenix, a Nitecore or whichever, check out the beam distance stated and candella. The higher the candella per lumen the better it throws.

If you are in a truck, I would suggest a 12V rechargable incan/halogen pistol grip search spot light thrower. Optimal CRI and tint with larger reflector means possible 100s of yards range and multiple thousands of lumens possible depending on model. This type of light was made for these duties.

In foggy situations the narrower the beam the less the back scatter. Avoid the lumen chase, focus will help more than lumens. A neutral to warm tint helps as well. In central New York it is foggy most of the summer so I have tried many things to cut through dense fog. My best lights for this were all throwers, my Deft-x was one of the best and it only had about 1000 lumens. All throw and no spill, it would penetrate dense fog for about 150 feet before I couldn't see what I aimed at.

Lower (color) temperature, warmer tint.

Ignore Lumens, look for Candella.

TIR lenses are helpful. Got it.

I'm starting to think I should just scroll through bykfixer's post history, and start reading. By the time I'm done, I'll probably have answers to most of my questions.

Did you know that factory TIR lights are really hard to find? Surefire uses them on a couple of their smaller lights (Scout, Defender, some others), but it seems like they're the only ones using it regularly, and it's used in lights where size and total output are limited by their intended role.

Definitely go for throw over flood.