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Stealth bomber in flight on Google Maps

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Re: Stealth bomber in flight on Google Maps

#321

Post by jcims »

coderenegade wrote: post #301
jcims wrote: post #296

Earlier quoted context omitted.

It’s so bad it seems unlikely it isn’t a joke. I mean look at their mission patches: https://en.wikipedia.org/wiki/List_of_NRO_launches

The gorilla holding the US flag is my favourite. And it might just be me, but the Nemesis badge has to be a sphincter, right? It reminds me of the Greendale flag in community.

Mine is definitely L-66 https://en.wikipedia.org/wiki/File:NROL-66_Patch.png

Not a huge fan of the vector art badges though, I want some embroidery!

Re: Stealth bomber in flight on Google Maps

#322

Post by geoduck14 »

amcoastal wrote: post #257
samhw wrote: post #249

Earlier quoted context omitted.

This is incredibly cool. What's the application (if it's possible to obscure whatever details you don't want to divulge)?

Its coastal physics work, you can infer near shore conditions by watching wave propagation.

So... like where submarines are based on water disturbances?

Re: Stealth bomber in flight on Google Maps

#323

Post by dylan604 »

coderenegade wrote: post #301
jcims wrote: post #296

Earlier quoted context omitted.

It’s so bad it seems unlikely it isn’t a joke. I mean look at their mission patches: https://en.wikipedia.org/wiki/List_of_NRO_launches

The gorilla holding the US flag is my favourite. And it might just be me, but the Nemesis badge has to be a sphincter, right? It reminds me of the Greendale flag in community.

I like how they quit looking like patches and just turned into stickers. Even with a black budget, they still had to cut corners and reduce spending on incidentals too?

Re: Stealth bomber in flight on Google Maps

#324

Post by wodenokoto »

ihattendorf wrote: post #226
Phrodo_00 wrote: post #197

Earlier quoted context omitted.

> Rather than taking a photograph, satellite sensors record electromagnetic radiation in the red, blue, green, and high-resolution panchromatic (black-and-white) bands (as well as several not visible to the human eye, as this Mapbox[2] post helpfully explains). When these bands are combined to produce a visible image That's the same as taking a (normal, digital) photograph (sans additional non-rgb layers), just expla…

The difference is typical digital cameras have a bayer filter in front of the sensor to allow taking a single color picture vs. here it sounds like multiple captures with individual filters (e.g. 1 blue, 1 red, 1 green, 1 monochrome) that are later combined into a color picture.

The point was at all color photos record electromagnetic radiation in visible colors.

The “it doesn’t take photos it record electromagnetic radiation” is a silly thing to say.

Re: Stealth bomber in flight on Google Maps

#325

Post by namibj »

AussieWog93 wrote: post #259
nopenopenopeno wrote: post #247

Earlier quoted context omitted.

Is CMOS a type of pushboom sensor?

CMOS is a manufacturing method for integrated circuits. Any type of sensor could be CMOS.

I haven't seen a CCD CMOS, yet, and I don't _think_ microbolometers are CMOS-based (and wouldn't be surprised if no one publically tried). Happy to see some exotic examples, though. Those are always intriguing the hacker curiosity.

Re: Stealth bomber in flight on Google Maps

#326

Post by namibj »

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.

It's standard when using reflectic/catadioptic objectives to peek back at where the satellites are: https://www.astroshop.eu/filter-wheels-filter-sliders/starli... This one has USB, the same style with manual operation via a teethed wheel is like 169 EUR at that shop. Or consider rigging a burnt-out DLP projector's filter wheel up, which comes with a motor and encoder that you could use to capture imagery with the filters they provide at much higher frame rates (a few hundred fps in the monochrome domain seem usual these days, AFAIK, for good consumer DLP projectors).

Re: Stealth bomber in flight on Google Maps

#327

Post by thot_experiment »

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…

Fun fact: this is called a Harris Shutter effect when it's done for art purposes.

Re: Stealth bomber in flight on Google Maps

#328

Post by ryan_j_naughton »

oppositelock wrote: post #308
dalmo3 wrote: post #306

Earlier quoted context omitted.

I've seen larger aberrations from satellite captures of planes. But I've no idea how to estimate height or speed by that.

You can get height if you can find the shadow, and find the time that the photo was taken, because at any given time and date, you can compute sun position, and you know the precise lat/lng of the shadow. The shadow would need to be in the same photo, though. (actually, it's a bit to the northwest, just found it). If you can find a vertical structure, like an antenna mast, you can measure shadow length and direction…

For those interested, here is the shadow: https://www.google.com/maps/place/39%C2%B001'28.8%22N+93%C2%...

Took me a while to find it, so thought I'd save someone else the scrolling/search cost.

Re: Stealth bomber in flight on Google Maps

#329

Post by magicroot75 »

amcoastal wrote: post #239
kevin_thibedeau wrote: post #118

Earlier quoted context omitted.

These are pushbroom linear sensors stacked up in the focal plane. The spectral channels are physically separated by larger distance than neighboring pixels in a Bayer grid. There is a time delay between each channel sweeping over the same location that gets corrected when the final imagery is aligned. The moving plane at altitude violates assumption of a static scene and exposes the scanning behavior.

Exactly! I'm working on some stuff now to exploit this very effect, the small time difference in the bands can be used to find velocities of moving objects.

Is this at all analogous to how we used red/blue shift to determine the speed at which astronomical objects are moving towards/away from us?

Re: Stealth bomber in flight on Google Maps

#330

Post by magicroot75 »

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…

Wait until you see what's hiding in the cornfield under the B-2.
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