320-Gigapixel Photo of London is World's Largest Panoramic Photo

From BT Tower's website:

BT Tower breaks world record for panoramic photo

An amazing image of London taken from the top of the BT Tower has set a new record for the world’s largest panoramic photo. The image shows a full 360 degree view of London in incredible detail.

The 320 gigapixel image, taken by expert photography firm 360Cities, comprises more than 48,000 individual frames which have been collated into a single panorama by a powerful workstation. It is the first time that an image of this magnitude has ever been attempted, and it took several months to create due to the scale of the endeavour. If printed at normal photographic resolution, the BT Tower panorama would be 98 meters across and 24 meters tall, almost as big as Buckingham Palace. In comparison, the last record attempt for a London panorama was 80 gigapixels, taken from Centrepoint in 2010.

Project by numbers:

• 320 – the number of gigapixels in the photo
• 48,640 – the number of individual images shot
• 3 – the number of days it took to shoot all the individual photos
• 3 – the number of months over which the computer processed the final result
• 60,000 – times bigger than an iPhone 4 photo
• 98 – the number of meters long if printed in normal photographic resolution
• 24 – the number of meters high if printed in normal photographic resolution
• 29th – The floor at the BT Tower where the photos were taken
• 20 – number of miles distant to the viewable horizon

Technical photographic information, and how the photo was taken:

• Working over a period of three chilly days in 2012, the 360Cities team spent hours on the 29th floor outdoor platform of the BT Tower working with four cameras to record the 48,640 images comprising the panorama.
• Four Canon EOS 7D cameras with EF 400mm f/2.8L IS II USM lenses and Extender EF 2x III teleconverters were mounted on Clauss company Rodeon VR Head ST robotic panorama heads and positioned in four secure locations around the 29th floor platform.
• The Clauss company robotic panorama heads are capable of 72,000 steps in a single 360 degree arc, and in this case were set to fire four frames a second.
• Laptops monitored a live preview of the progress of the shoot, which was accomplished in the teeth of sub-freezing temperatures and occasional 50 mph winds high above London.
• The 360Cities photography team of Jeffrey Martin, Tom Mills and Holger Schulze ensured that not a single individual frame from the more than 48,000 planned was missed.
• The raw images were then processed over a multi-week period using Fujitsu Technology Solutions’ Celsius R920 workstation with 256GB of RAM and 16 cores at 3.1GHz, and Autopano Giga panorama stitching software from Kolor.
• The resulting online interactive version of the photo is presented in multi-layered, tiled resolution that permits zooming in to view extreme details, and is composed of millions of individual image tiles.

See the full BT Tower Press Release and check out the amazing 320-gigapixel panoramic photo.