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How to Hide from a Drone

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Re: How to Hide from a Drone

#101

Post by russholmes »

ISL wrote: post #58
russholmes wrote: post #53

Earlier quoted context omitted.

The Rayleigh limit in spatial resolution of an image forming device is given by: l = 1.22 * λ * L / D Where λ is wavelength, L is distance and D is optical element diameter. For satellite at an altitude of 150 km with 2.4 m diameter mirror and 0.4 μm blue light, this gives a spatial resolution of 0.3 m. To read a number plate requires an order of magnitude better than this.

Thus an interferometric imaging system can theoretically do it ( two input scopes separated by 24m). The hard part is the atmosphere.

In one axis, and I don't think they were capable of doing it at the time suggested.

Re: How to Hide from a Drone

#102

Post by alacombe »

ashtonkem wrote: post #92
gruez wrote: post #75

Earlier quoted context omitted.

>What people tend to ignore is that the defenders do this while sustaining much higher casualties Is this supposed to be a good thing for the defender? The us has been there for more than a decade and the defenders weren't running out of combatants.

I mean, there’s no way to look at tens of thousands of deaths and declare it to be a good thing. I say it because usually in common discussion people forget that the defenders in this scenario hold out despite higher casualties, not due to the lack of them.

> I mean, there’s no way to look at tens of thousands of deaths and declare it to be a good thing.

Yes, there is. It was called the Russian WWII front where the Russians sent to the meat grinder by the tens of thousands held back the German army until winter and supply issues decimated them. It is a viable strategy to deal with a lack of equipment.

Whether or on it is acceptable to say on HN is another story.

Re: How to Hide from a Drone

#103

Post by ashtonkem »

alacombe wrote: post #102
ashtonkem wrote: post #92

Earlier quoted context omitted.

I mean, there’s no way to look at tens of thousands of deaths and declare it to be a good thing. I say it because usually in common discussion people forget that the defenders in this scenario hold out despite higher casualties, not due to the lack of them.

> I mean, there’s no way to look at tens of thousands of deaths and declare it to be a good thing. Yes, there is. It was called the Russian WWII front where the Russians sent to the meat grinder by the tens of thousands held back the German army until winter and supply issues decimated them. It is a viable strategy to deal with a lack of equipment. Whether or on it is acceptable to say on HN is another story.

I’d call that necessary or the lesser of two evils, not good.

Re: How to Hide from a Drone

#104

Post by 01100011 »

tgsovlerkhgsel wrote: post #45
01100011 wrote: post #3

I don't know if it would be effective at hiding you beyond the next few years when more comprehensive systems are in place, but I think a simple circuit that randomly blinks an IR LED would be handy. Something like an an LED throwie, but with random cycling. Put a bunch of them around and you'll probably screw up most cheap CCDs by forcing them to constantly adjust their exposure. Sure, a cheap filter can defeat them…

a) Having a large blinking marker draw attention to your area would already be highly noticeable. b) that IR LED would have to be extremely powerful to overwhelm a camera that is looking at a larger area

I'm thinking more along the lines of covering yourself or your immediate area in a collection of randomly flashing IR LEDs. It's not about blending in, it's about defeating current CCD cameras. Obviously it is just going to attract attention to you when 'sensor fusion' becomes more prevalent. It's for when you want to appear as a glowing ball of light on a surveillance feed and not have your face or gait captured.

Re: How to Hide from a Drone

#105

Post by alacombe »

ashtonkem wrote: post #103
alacombe wrote: post #102

Earlier quoted context omitted.

> I mean, there’s no way to look at tens of thousands of deaths and declare it to be a good thing. Yes, there is. It was called the Russian WWII front where the Russians sent to the meat grinder by the tens of thousands held back the German army until winter and supply issues decimated them. It is a viable strategy to deal with a lack of equipment. Whether or on it is acceptable to say on HN is another story.

I’d call that necessary or the lesser of two evils, not good.

> I’d call that necessary or the lesser of two evils

Which is literally the very definition of _good_ -

"In most contexts, the concept of good denotes the conduct that should be preferred when posed with a choice between possible actions"

-- https://en.wikipedia.org/wiki/Good

Re: How to Hide from a Drone

#106

Post by alacombe »

ashtonkem wrote: post #54
alacombe wrote: post #33

Earlier quoted context omitted.

Yet, the US has pretty much been kept at bay from Irak and Afghanistan, go figure... In general, the US army is not equipped for guerilla-style warfare, and especially not on US soil. Local PD are another story on this point, but far less equipped.

On one hand it’s clear that a guérilla campaign is fully capable of resisting a first class army for a long period of time; this has been clear since the 1970s. What people tend to ignore is that the defenders do this while sustaining much higher casualties . Oh, and civilian casualties are typically an order of magnitude higher because high explosives aren’t very discriminatory. On one hand, that’s an interesting di…

> On the other it is not a convincing argument about how you shouldn’t be too worried about the US military

Another argument is that the US military is likely to be split in case of direct intervention on US national soil, including in support of the National Guard or local PD. Same goes for the National Guard or local PD - ACANB [All Cops Are Not Bastards]. Not to mention the +350 millions firearms (and associated ammunitions & gears) owned by Americans.

Re: How to Hide from a Drone

#107

Post by b112 »

ohazi wrote: post #98
b112 wrote: post #26

Earlier quoted context omitted.

https://news.google.com/newspapers?id=nugbAAAAIBAJ&sjid=kFEE... Under 'twenty questions', second column, end of column, under highlights "Big Bird" satellite. Again, you may be right. However there are many claims that this capability existed in the 80s. Suggest you research some of the satellites of the time, including ones which worked on film, and jettisoned rolls of it for terrestrial pickup.

> Suggest you research some of the satellites of the time Suggest you do the same. Here's the "Big Bird" satellite you referred to: https://en.m.wikipedia.org/wiki/KH-9_Hexagon > The cameras could scan contiguous areas up to 120 degrees wide, and achieved a ground resolution better than 2 ft (0.61 m) during the later phase of the project. The sources you cite are, to put it nicely, propaganda. The physics simply does…

> Another commenter correctly pointed out that these claims would violate the diffraction limit by more than an order of magnitude, and that's assuming zero atmospheric interference, which is absolutely not the case.

Yet this comment was refuted, and you have not addressed that fully.

> Why do you think film is relevant here?

As per the timeline, my comment with the film reference was written prior to any discussion about noise, or diffraction.

It was simply there to demonstrate the lengths gone, 2 decades prior to the 80s, in the 60s, to get imagery back to Earth.

I was curious how they did it in the early days, as video transmission technology was nascent. It quite certainly would have been a potential massive blocker on quality, from satellite to surface. Film seemed to solve that aspect of things in those early days.

I found this highly interesting. Film, from multiple lenses, the ultimate sneaker net (yes, it's analog, but still...)

Anyhow, over the years I've seen so many technical issues overcome, with sideways attacks on the problem. When people start saying "But... impossible!", I tend to have a high degree of skepticism.

I will say this though. Yes, it certainly could have been propaganda.

Doesn't mean it was, but I certainly do agree the potential is there.

Re: How to Hide from a Drone

#108

Post by 0xdeadb00f »

uselesscynicism wrote: post #88
0xdeadb00f wrote: post #81

Earlier quoted context omitted.

I have no faith in what my vote can do in regards to things like this. Paying attention doesn't do much. If the government wants to pass something, especially in the name of national security, it will get passed.

Then what? If you can't vote to get the change that you want, what's the alternative? Violent revolution and hoping that the new boss is better than the old boss? I'm so tired of this kind of useless cynicism. Voting matters, especially at the local level. You can get involved in your party at local levels, too. How do you think all these politicians get into the political class to begin with, in free societies? Or s…

I don't deny that voting matters. And I still vote for those who share my ideals.

But my point is that voting isn't everything - the government can do whatever they want in the name of national security. Which is an obvious problem, but something that they can scare monger people into agreeing with.

Re: How to Hide from a Drone

#109

Post by LargoLasskhyfv »

01100011 wrote: post #3

I don't know if it would be effective at hiding you beyond the next few years when more comprehensive systems are in place, but I think a simple circuit that randomly blinks an IR LED would be handy. Something like an an LED throwie, but with random cycling. Put a bunch of them around and you'll probably screw up most cheap CCDs by forcing them to constantly adjust their exposure. Sure, a cheap filter can defeat them…

That just makes you a more interesting target, putting a glowing marker around you.

Re: How to Hide from a Drone

#110

Post by LargoLasskhyfv »

NikolaeVarius wrote: post #71
londons_explore wrote: post #66

Earlier quoted context omitted.

I assume that most militaries have satellites with radars that can penetrate most ceilings to see planes in hangars etc. Most militaries also have access to some high orbit satellites that have 24x7 coverage of an area, and then some low orbit satellites which fly overhead every few hours and can grab high res shots. The combination makes it very hard to sneak a secret plane from one building to another between orbit…

You're going to have to define "most" I'm pretty sure "no" militaries have 24/7 coverage of any area on the planet.

For now...
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