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Ralph
06-10-2013, 02:20 PM
Considering the latest story about NSA snooping this might be of interest.

This picture was taken with a camera 70,000 x 30,000 pixels (2100 MegaPixels). The cameras are not sold to the public and are being installed in strategic locations. (This one is in Canada)

Actually this is a composite image made up of a bunch of photos taken over time. There are double images of people scattered throughout this image.

Place the cursor in the multitude of people and left double click a couple times.
It will continue to show the people much closer, when you double left click again
or click more if needed. There were thousands of persons and yet one can spot and recognize any face. I would imagine facial recognition software will also work here.

Imagine what this means... both police and Army have it.

http://www.gigapixel.com/image/gigapan-canucks-g7.html

This is a digital camera. However, when I was taking the photo interpretation course at Fort Sill in the early '60s we had prints of some photos taken by the cameras on the U2 of the missile installations in Cuba. The U2 flew at 100,000 ft. with cameras that allowed seeing a wrench near a missile silo being built with enough resolution that you could estimate the size of the wrench.

We also used strip films. The camera shutter is opened and the film stripped by at the same rate of speed that the plane was flying. These were at lower altitude but the plane would drop down, fly level and cross the island so fast that there was no chance of intercept. I recall seeing a very surprised soldier, rifle at mid-drop, looking up with enough resolution that you could easily recognize the face.

I imagine there has been some improvements since then.

Mel
06-10-2013, 02:31 PM
Thanks for posting this Ralph. That is just absolutely unbelievable!!

Mel

Ralph
06-10-2013, 03:04 PM
Notice that you need no enhancment appled, the image is there, it's just too small to see until you zoom in.

This has medical application, too. My VA hospital has gone entirely to high-resolution digital X-rays. The tech told me he hasn't used film in several years. The image is available within seconds after exposure and is the equivalent of a film about 8 x 10 FEET. All of the images are included in your digital medical file and can be examined by a radiologist anywhere in the world. In addition each shot is much cheaper than film, maybe 1-2% of the film cost and eliminates the whole photo lab, storage costs, envelopes and so forth.

That's the good side. The bad side with the NSA stuff is that there is nothing that can't be misinterpreted or used in ways other than intended. Data mining was widely credited with Obama's win. The Republicans used it to, buying expensive commercial databases, but I really have o wonder if the NSA database wasn't used by the sitting president to further his own ambitions.

J, Edgar Hoover was supposed to have private files he (illegally) got by using FBI resources investigating the Washington insiders and using their various misdeeds as blackmail to maintain his own power. The only people I trust with that type of information are those who don't want it. Given the nature of the bureaucracy, how likely do you think those who crave power and position can resist the urge to use the NSA database for their own puposes?

Echo63
06-12-2013, 09:40 AM
Hi Guys, this is my first post on the Forum

Ralph, while i am sure that the military and police have cameras capable of much higher resolutions than we can buy on the open market, i feel you are wrong about this image.

its on the Gigapixel webpage, which means it has most likely been done with a Gigapan, im going to guess by a photojournalist from a large local paper.
A gigapan is a electronic tripod head and a seperate software package that allows multiple images to be stitched together to create a panorama.

I have used a Gigapan (we have a Gigapan Epic Pro at work) and they are easily available on the open market, they cost around $1000 australian dollars, weigh a few kilogrammes, and can easily be setup on a tripod in about 10 minutes.
the Gigapan unit is a Robotic camera mount, that is designed to work with an SLR or compact camera and take a picture, reframe and take another picture, then move slightly and reframe again, the images all have a little bit of overlap to allow easy stitching later - basically it automates a process photographers have been using for years.
this image, as stated in the text across the top is made up of 216 images, 12 images wide, and 18 images vertically - which is much bigger than any i have shot (my biggest was 12 images across by 6 images high)

the separate software "stitches" the images together - you point it to a folder of pictures, and it knows where they all go due to the order, but it blends the seams so its difficult to tell the image is a composite (it works better on still images, rather than crowds of people, people move and doubles appear)
the finished file can be uploaded to the gigapixel site, like this one has been, where it can be viewed much like a google earth sattelite image, or turned into an ordinary JPEG image, and shared in print/via the internet, although the finished files are very large, so sending them can be an issue.

(also - just guessing by the image size, and clarity it was taken with a pro level DSLR and a 200ish mm lens - probably either a Canon 1Dmk4, 1DX or Nikon D3 or D4)

i have a large stitched image of the city of perth, sitting on my computer at work - i will try and share it via dropbox if you are interested