Feeds

Spies in the sky: The leaps and bounds from balloons to spook sats

A brief history of aerial surveillance around the globe

Bridging the IT gap between rising business demands and ageing tools

We can thank the CCD for the today's high-resolution satellite imagery, but until the 1970s, everything shot from above had to be recorded on physical media.

No doubt Gaspard-Félix Tournachon struggled aloft with a glass plate camera for his first shots of Paris over 150 years ago, and by the Great War aerial photographers were still grappling with cumbersome devices, albeit a little more user-friendly.

By 1917, the British Williamson P7 camera packed a handy magazine of 24 glass plates of 5in x 4in, but the same manufacturer's WW2 F.24 had embraced roll film, offering up to 250 5in x 4in exposures.

The F.24 system offered interchangeable lenses at focal lengths of 5in, 8in, 14in and 20in, but the image format lacked detail at even the longest of these when photos were taken from high altitude.

The larger F.52 used a 8.5in x 7in film format, with up to 500 exposures available in a single magazine. Optional longer lenses of 36in and 40in focal lengths addressed the resolution from altitude issue.

A montage of aerial surveillance cameras

Post-war surveillance programmes saw the design of increasingly complex roll-film cameras, with many of the US's needs met by the Itek Corporation. The company's HYAC-1 panoramic model, used in the Genetrix balloon missions, led to 70mm film stock models for Corona.

The first Corona launches used a single camera, quickly replaced with a twin-camera set-up dubbed "MURAL" (see above). The cameras' 24in (610mm) focal length lenses - ultimately supplied by 4,900m of film each - could initially resolve objects on the ground of 12m in diameter.

Improvements in the system allowed later Corona satellites to resolve objects just 1.5m in diameter.

By contrast, the folding optics telescope design of the KH-11 satellites' cameras, with a primary mirror of around 230cm and an 800 x 800px CCD, could - based on analysis of leaked photographs - resolve down to 14cm.

While the prospect of photographing a grapefruit from space is a delicious idea, high-altitude fruit surveillance is sadly beyond the pockets of mere mortals.

Next week, we'll have a look at the thriving DIY spy-in-the-sky scene - from UAVs to High Altitude Ballooning (HAB), and give a few pointers as to how those with less than multi-billion dollar budgets can mount their own aerial reconnaissance mission.

In the meantime, we'll leave you with this montage from our Paper Aircraft Released Into Space (PARIS) mission, demonstrating how a balloon, a tank of helium and a $100 camera can provide breathtaking bangs for not many bucks...

Composite image from our PARIS mission

®

Mobile application security vulnerability report

More from The Register

next story
Bad back? Show some spine and stop popping paracetamol
Study finds common pain-killer doesn't reduce pain or shorten recovery
Malaysian Airlines flight MH17 claimed lives of HIV/AIDS cure scientists
Researchers, advocates, health workers among those on shot-down plane
World Solar Challenge contender claims new speed record
One charge sees Sunswift travel 500kms at over 100 km/h
Mwa-ha-ha-ha! Eccentric billionaire Musk gets his PRIVATE SPACEPORT
In the Lone Star State, perhaps appropriately enough
SMELL YOU LATER, LOSERS – Dumbo tells rats, dogs... humans
Junk in the trunk? That's what people have
All those new '5G standards'? Here's the science they rely on
Radio professor tells us how wireless will get faster in the real world
The Sun took a day off last week and made NO sunspots
Someone needs to get that lazy star cooking again before things get cold around here
prev story

Whitepapers

Designing a Defense for Mobile Applications
Learn about the various considerations for defending mobile applications - from the application architecture itself to the myriad testing technologies.
How modern custom applications can spur business growth
Learn how to create, deploy and manage custom applications without consuming or expanding the need for scarce, expensive IT resources.
Reducing security risks from open source software
Follow a few strategies and your organization can gain the full benefits of open source and the cloud without compromising the security of your applications.
Boost IT visibility and business value
How building a great service catalog relieves pressure points and demonstrates the value of IT service management.
Consolidation: the foundation for IT and business transformation
In this whitepaper learn how effective consolidation of IT and business resources can enable multiple, meaningful business benefits.