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Stealth bomber in flight on Google Maps

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Re: Stealth bomber in flight on Google Maps

#71

Post by mmaunder »

MontyCarloHall wrote: post #9

Interesting how the three separate R/G/B images are taken independently a few ~seconds~ milliseconds apart, with a different color filter placed over the image sensor. I assume this is to maximize resolution, since no Bayer interpolation [0] is needed to demosaic the output of a traditional image sensor that integrates the color filters onto the sensor pixels themselves. As these satellites are not intended to photog…

Also came here to discuss this. Super interesting opportunity to reverse what they're doing. Yeah I'd agree it's color filters which would avoid duplicating lenses (probably the most expensive component) or dividing the light energy. Filters would give you the most photons per color per shot. I wonder if the filters are mechanical or electronic somehow. As another commenter calculated, it's 10ms between shots, which is not that impractical to move physical filters around when you consider modern consumer camera shutter speeds of around 0.125 milliseconds max.

Re: Stealth bomber in flight on Google Maps

#72

Post by dheera »

goblin89 wrote: post #33
MontyCarloHall wrote: post #9

Interesting how the three separate R/G/B images are taken independently a few ~seconds~ milliseconds apart, with a different color filter placed over the image sensor. I assume this is to maximize resolution, since no Bayer interpolation [0] is needed to demosaic the output of a traditional image sensor that integrates the color filters onto the sensor pixels themselves. As these satellites are not intended to photog…

I wonder if there are ways to get superior (compared to Bayer) color images from conventional raw-capable monochrome digital cameras (like Leica Q2 Monochrom) in static scenes using similar workflows of taking three separate shots.

I wouldn't be surprised if these military bombing dudes not only took R, G, B, but also near IR, far IR, UV, and various other things. If they did it would make no sense to try to make a Bayer filter for all of that and rather just have multiple filtered cameras pointed at the same direction.

Re: Stealth bomber in flight on Google Maps

#73

Post by thrtythreeforty »

goblin89 wrote: post #33
MontyCarloHall wrote: post #9

Interesting how the three separate R/G/B images are taken independently a few ~seconds~ milliseconds apart, with a different color filter placed over the image sensor. I assume this is to maximize resolution, since no Bayer interpolation [0] is needed to demosaic the output of a traditional image sensor that integrates the color filters onto the sensor pixels themselves. As these satellites are not intended to photog…

I wonder if there are ways to get superior (compared to Bayer) color images from conventional raw-capable monochrome digital cameras (like Leica Q2 Monochrom) in static scenes using similar workflows of taking three separate shots.

Many cameras, especially medium format like Fuji GFX, can do "pixel shift" capture, where they use the sensor stabilization to shift the sensor by one pixel at a time to ensure red, green, and blue are each captured at all pixels, without needing demosaicing. The camera has to be mounted on a tripod for this to work - like any stacking requires, really.

Re: Stealth bomber in flight on Google Maps

#74

Post by cossatot »

msisk6 wrote: post #45

I live on a farm very close to this area. All the B-2s are based at nearby Whiteman Air Force Base. They fly over often -- one even fly over my farm today about an hour ago. This one was probably on final approach during the summer when the winds are usually out of the south and was probably about 2,000 feet above the ground.

Yeah I remember being thrilled seeing them while canoeing on the Gasconade when I was a kid in the 90s. I believe that we saw one refueling behind a KC-10 in the air as well.

Re: Stealth bomber in flight on Google Maps

#76

Post by mrcode007 »

MontyCarloHall wrote: post #9

Interesting how the three separate R/G/B images are taken independently a few ~seconds~ milliseconds apart, with a different color filter placed over the image sensor. I assume this is to maximize resolution, since no Bayer interpolation [0] is needed to demosaic the output of a traditional image sensor that integrates the color filters onto the sensor pixels themselves. As these satellites are not intended to photog…

Different wave lengths travel at different speeds through glass and air and focus differently even on the same lens when color photos are taken in the single frame.

https://en.m.wikipedia.org/wiki/Chromatic_aberration

Re: Stealth bomber in flight on Google Maps

#77

Post by [deleted] »

ericbarrett wrote: post #27
MontyCarloHall wrote: post #9

Interesting how the three separate R/G/B images are taken independently a few ~seconds~ milliseconds apart, with a different color filter placed over the image sensor. I assume this is to maximize resolution, since no Bayer interpolation [0] is needed to demosaic the output of a traditional image sensor that integrates the color filters onto the sensor pixels themselves. As these satellites are not intended to photog…

My napkin calculations are that the three channels are ~10ms apart, given the bomber is 69 feet nose-to-tail* and an assumption of 400 mph velocity. * http://www.dept.aoe.vt.edu/~mason/Mason_f/B2Spr09.pdf

[deleted]

Re: Stealth bomber in flight on Google Maps

#78

Post by kens »

ajsnigrutin wrote: post #53
anormalpapier wrote: post #2

Not so stealth eh?

During the 1999 yugoslavia bombings, after the first one was shot down, there was a joking apology on the TV, something along the lines of "Sorry, we didn't see it" :)

The Serbians made a poster saying "Sorry, we didn't know it was invisible" after they shot down a stealth F-117. The full story and a picture of the poster at this link: https://www.warhistoryonline.com/instant-articles/serbs-shot...

Re: Stealth bomber in flight on Google Maps

#79

Post by jcims »

ericbarrett wrote: post #52
ATsch wrote: post #42

Earlier quoted context omitted.

I would assume that the plane or satellite moving affects this too, it's presumably being corrected but there might be some parallax.

You're absolutely correct, but as the aircraft is much closer to the ground than the imaging satellite I disregarded it. Spherical cows and all that :) I'm sure a military analyst would do the calculations!

It actually works out to be pretty close. A satellite flying ~17k mph at 250 miles altitude would largely have the same angular displacement from the ground as a plane moving 400 mph at 31,000 feet. Most satellites fly in an easterly direction, so the question would ultimately be what the inclination of the orbit is relative to the direction of flight.

Re: Stealth bomber in flight on Google Maps

#80

Post by zelon88 »

ssnistfajen wrote: post #69
Quentak wrote: post #25

Screenshot for when it will have been deleted by Google https://i.imgur.com/toSC5a0.png .

Would be disappointing for them to remove it for basically no reason, especially considering you can see a B-2 parked on the tarmac ( https://www.google.com/maps/place/38%C2%B043'29.9%22N+93%C2%... ) in the nearby Whiteman AFB. The B-2 was first flown 32 years ago. Its existence is neither covert or secret, but often used to do flybys at freaking football games where thousands of recording devices are present and act…

Correct, but don't misunderestimate the power of knowledge.

Let's assume that some adversary is out there keeping track of these planes, and knows that they can scan Google maps for the RGB artifact by the engines to locate them reliably and programmatically.

Now Google maps becomes a repository for information that adversary may use to validate other information. Maybe this confirms the schedule for some training excersise. Maybe this particular B2 being in this location validates or invalidates other information about US troop strength abroad.

I was taught to always "assume your adversary is capable of going through your trash" and try to prepare my "trash" accordingly.

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