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How StolenCameraFinder and EXIF Work

I found a unique website the other day called StolenCameraFinder – I lost my Sony A200 DSLR a while ago so I decided to give StolenCameraFinder a go to see what it could do for me.

In a nutshell, you upload a photo taken by the stolen/lost camera to the website. It then cross references a unique serial number which is found in the picture against a large database of serial numbers. If the serial number is found in the database, it could potentially mean that a photo was taken from your camera and uploaded online after it was lost/stolen.

The website uses the EXIF data in your pictures to find this serial number. EXIF, which stands for exchangeable image file format, is data which is ’embedded’ into each photo your camera takes. Data such as when the photo was taken, whether the flash was fired, brightness, ISO, resolution, etc is stored in the EXIF (Sample of EXIF is given at the end of the article).
Amongst this data is a unique serial number which is provided by the camera (some older cameras like my Sony A200 do not save the camera serial number in the EXIF which is a shame).

StolenCameraFinder has a huge database of these serial numbers and the website the photos were posted on by a method called ‘scraping’.
Scraping is a bit like what search engines do to find content over the internet. They visit each and every page on every site to find new content and put them on their search engine.
StolenCameraFinder does the same thing – it scrapes popular image sites such as Flickr for photos which are then scanned for their EXIF data; specifically for serial numbers, camera brand and model. This data is then stored in the StolenCameraFinder database which others will use to hopefully find their lost/stolen camera.

That’s when you or I come along with a lost or stolen camera. We upload a picture previously taken with our camera to StolenCameraFinder. StolenCameraFinder then takes the unique serial number of our camera and searches its database to see if it has found any other photos posted online which has the same serial number as our camera. If it does, then that means that someone is taking photos with our camera!

Jeffrey’s Exif Viewer is another good website which I came across which you can use to find out exactly what EXIF data your photos spit out. A sample of the EXIF from my Sony A200 can be seen below.

Sample of EXIF Data