Infravision [10]

Not · 11-21-2014, 04:27 PM

I have infravision. Does it help when I'm driving in a fog, or do I need para-radar?

McAllister · 11-21-2014, 04:41 PM

It will help you not to hit anything that's very hot, but I wouldn't drive by it. I reckon IRvision is less impeded by fog than other vision, but, again, it won't help you see the road, rocks, signs, or much else.

roguebfl · 11-21-2014, 05:56 PM

The problem with Fog, is unlike darkness there is actually something physically there obscuring you vision that has it's own temperature. So is partial cover type obscuring.

Fred Brackin · 11-21-2014, 06:03 PM

At an ultimate level of detail it would be a complex comparison between the way water droplets absorb infrared (the thermograph frequencies) and the way they refract visible light frequencies.

Infravision will not be unimpeded by fog but might take a lesser penalty. Any species of radar or air sonar will ignore fog though.

Anthony · 11-21-2014, 07:12 PM

IR vision in fog will almost always be better than trying to see by a carried light, for the simple reason that you aren't throwing out beams that backscatter and blind you. How it compares to passive visual detection (e.g. seeing someone's lights in a fog when you don't have your own lights on) is going to depend on what you're detecting and what the fog is like.

Agemegos · 11-21-2014, 10:06 PM

Quote:

Originally Posted by Fred Brackin

At an ultimate level of detail it would be a complex comparison between the way water droplets absorb infrared (the thermograph frequencies) and the way they refract visible light frequencies.

Infravision will not be unimpeded by fog but might take a lesser penalty. Any species of radar or air sonar will ignore fog though.

I found a short paper about it: http://www.akgec.in/journals/Jan_June13/1-Sauf.pdf.

The take-away is that it won't help in Category III conditions (with visibility less than 300m), and that middle-wavelength IR is more helpful than near IR. But on light fog (category I conditions) IR vision gear will give you four times the visibility range that visible light would.

Not · 11-21-2014, 11:10 PM

So what, maybe -2 to vision rolls?

Toptomcat · 11-21-2014, 11:30 PM

If you're *driving* with infravision, your biggest problem probably isn't with the fog: it's with the windshield.

Not · 11-22-2014, 06:03 AM

Good point. Switch to motorcycle.

vicky_molokh · 11-22-2014, 06:04 AM

Quote:

Originally Posted by Not

Good point. Switch to motorcycle.

Without helmet and without windshield?

11-21-2014, 04:27 PM	#1
Not Join Date: Feb 2013	Infravision [10] I have infravision. Does it help when I'm driving in a fog, or do I need para-radar? __________________ Leave this space blank.

11-21-2014, 04:41 PM	#2
McAllister Join Date: Jun 2013	Re: Infravision [10] It will help you not to hit anything that's very hot, but I wouldn't drive by it. I reckon IRvision is less impeded by fog than other vision, but, again, it won't help you see the road, rocks, signs, or much else.

11-21-2014, 05:56 PM	#3
roguebfl Dog of Lysdexics Join Date: Oct 2004 Location: Melbourne FL, Formerly Wellington NZ	Re: Infravision [10] The problem with Fog, is unlike darkness there is actually something physically there obscuring you vision that has it's own temperature. So is partial cover type obscuring. __________________ Rogue the Bronze Firelizard Gerald Grenier, Jr. Hail Eris! Rogue's Weyr

11-21-2014, 06:03 PM	#4
Fred Brackin Join Date: Aug 2007	Re: Infravision [10] At an ultimate level of detail it would be a complex comparison between the way water droplets absorb infrared (the thermograph frequencies) and the way they refract visible light frequencies. Infravision will not be unimpeded by fog but might take a lesser penalty. Any species of radar or air sonar will ignore fog though. __________________ Fred Brackin

11-21-2014, 07:12 PM	#5
Anthony Join Date: Feb 2005 Location: Berkeley, CA	Re: Infravision [10] IR vision in fog will almost always be better than trying to see by a carried light, for the simple reason that you aren't throwing out beams that backscatter and blind you. How it compares to passive visual detection (e.g. seeing someone's lights in a fog when you don't have your own lights on) is going to depend on what you're detecting and what the fog is like. __________________ My GURPS site and Blog.

11-21-2014, 11:10 PM	#7
Not Join Date: Feb 2013	Re: Infravision [10] So what, maybe -2 to vision rolls? __________________ Leave this space blank.

11-21-2014, 11:30 PM	#8
Toptomcat Join Date: Jan 2009	Re: Infravision [10] If you're driving with infravision, your biggest problem probably isn't with the fog: it's with the windshield.

11-22-2014, 06:03 AM	#9
Not Join Date: Feb 2013	Re: Infravision [10] Good point. Switch to motorcycle. __________________ Leave this space blank.