Jim Lux wrote: > At 10:57 AM 10/30/2006, Robert G. Brown wrote: >> On Mon, 30 Oct 2006, Geoff Jacobs wrote: >>>>>> Mmm... Except... The high res images are from a plane because you >>>>>> can't >>>>>> really make out the fine details from a satellite through the earth's >>>>>> atmosphere. >>>> >>>> It's true that most of the Google Earth images are aerial photos, but >>>> I would imagine that one can get 10s of centimeter resolution from >>>> orbit >>>> on Earth (assuming that clouds aren't in the way). An old >>>> surveillance >>>> satellite (Corona) was doing better than 2 meter resolution in the >>>> 1970s. >>> >>> Absolutely. Assume modern recon sats use a primary mirror similar in >>> size to the Hubble primary (both made by Perkin-Elmer). Calculating the >>> Rayleigh limit for an Improved Crystal satellite such as that launched >>> with USA 186 (Apogee 1050km, Perogee 264km) gives a max resolution of >>> 7.9cm at 600nm and min resolution 31.5cm at 600nm. Space Imaging >>> typically quotes max res. of 1m with IKONOS. DigitalGlobe says 61cm in >>> B&W with their satellites. >>> >>> I would suspect that methods for dealing with atmospheric degradation is >>> the secret sauce in the NROs architecture, especially WRT real-time >>> applications of IMGINT. > > With a nice braadband pipe back to the ground, and a modest rack of > computers, amazing things are possible, including resolving things below > the diffraction limit. Look at the stuff people have been doing with > imaging ISS and Shuttle from the ground with fairly small telescopes. > Indeed, the variable atmosphere can actually help, because it > essentially gives you the ability to do multiple samples with > statistically independent distortions, so you can "average" them to > reduce the variance. Something else to do with that Beowulf sitting in > your garage.. I believe these techniques require multiple, short exposure samples. Apparently, KH-12s have a capability for real time video. I expect the frame rate from such would make multi-sampling a difficult noise reduction method to apply.
> > I seem to recall that the ambitious amateur can get resolutions less > than a meter with "available at retail stores" kind of optical equipment. > > There is a ground based optical observing site on Mt. Haleakala to do > just this sort of thing (or, at least, it's rumored to do so). > > >> Awww, what you guys are all trying to tell me seems to be that I >> shouldn't believe everything I see on 24. So agent Jack Bower really >> can't call back to CTU to track the driver of the grey mercedes from >> where he abandons the car to where he disappears into the abandoned >> military bomb shelter -- at night and independent of the LA weather and >> smog. > > IR imagery is one thing to think about. Radar is another. X band radar > (9-10 GHz) easily gives you 3cm sorts of resolution, especially with SAR > processing. IR imagery does allow remote sensing at night, but it is affected by weather. Also, IR typically has less resolution. Radar allows all-weather remote sensing. Radar antennas are more easily compacted for launch, too. However, you won't find Joe Taliban humping the Hindu Kush with SAR (unless you can image his Kalishnakov). >> You're really shaking my worldview here. Next you're going to tell me >> that Gil Grissom can't really prove that the sultry blonde did it from >> the tiny splinter removed from the carpet at the feet of the victim that >> could only have come from her imported chopsticks being hurled at high >> velocity through the victim's brain...;-) Or that they can take the >> blurred, crappy, low resolution picture from the surveillance videocam >> in the parking deck, load it into their CSI Windows GUI and click on it >> to prove that the perp was wearing argyle socks and had a mole on his >> left butt-cheek by mysteriously increasing the available pixel >> resolution by 2000% or so. You forgot the part where they determine a particle of pollen came from central Mongolia, which they then illustrate with a pretty little graph using GIS data that, I guess, they just have on hand. Then again, all this is about as realistic as having forensic technicians do interviews of murder suspects. >> I'll bet that MICROSOFT's CSI/beowulf software can do that and match >> fingerprints too...:-) But Macs are better at real life stuff... (wave hands vaguely) > But of course. You have the name wrong, though. That's MS Vista Crime > Scene Investigation/Clustering Edition, and the surveillance camera > imagery will need to be processed through an appropriate Digital Rights > Management system to make sure that you have properly licensed the right > to superresolution processing, no? > > Jim > > -- Geoffrey D. Jacobs Go to the Chinese Restaurant, Order the Special _______________________________________________ Beowulf mailing list, [email protected] To change your subscription (digest mode or unsubscribe) visit http://www.beowulf.org/mailman/listinfo/beowulf
