Hi,

Creator of the image here. First of all, thank you for all the attention, it's a real honor to be on the front page oF HN for almost a whole day now.

I am the founder of 360cities.net and creator of previous world record images such as "Prague 18 gigapixels", "Strahov Library 40 gigapixels" and "London 80 Gigapixels". This newest image was commissioned by BT as a kind of closing "Thank you London" gesture of the Olympic year. Of course, they didn't want "just" a jaw-droppingly enormous image, they wanted a world record image! Unfortunately, these things are getting a lot harder to accomplish, and we're starting to go up against some constrainsts of optics, air density, and so on.

So, to create this image, we needed 4 cameras shooting simultaneously in order to get all the images in a reasonable length of time. We needed the very best optics out there, and CMOS sensors with the smallest pixels (somewhat unfortunately this meant the 3 year old Canon 7D). We needed the fasted and most precise panoramic robots to mount the cameras on. We needed gigantic memory cards, 128GB, to store a full run of images on one card. We needed 4 laptops to copy the cards quick enough to shoot again (buying more cards wasn't in the budget). In short, we needed a ridiculous amount of gear - this took 2 days to set up.

We spent 3 days shooting. The first day it was raining, but we shot anyway to learn the gear and see what mistakes we might make. The second day there were 50km/h winds which, 150 meters up, is very cold and a little bit dangerous. We made sure the gear was triple secured, and we shot anyway. One of the three photographers threatened to leave the project. It was unpleasant. But we uncovered more issues which we were able to solve. Keep in mind the cameras were moving continuously, and focusing, and shooting - they never stopped to take a shot. 12600 shots while moving and focusing each time? This required some very exacting work, knowing the gear, and maybe even a bit of luck.

Day 3 was clear, and not windy. We got 2 sets of images shot. All cameras got the shots they needed in 2 sets. That is 96000 images with not a shot missed. This to me is a huge technological achievement that i'm proud of, and I will sing the praises of Canon anytime someone asks me to :-)

Now, on to stitching. Normally I have no problem stitching 2 or 4 thousand images. But this is an order of magnitude more. As gabriel weinberg noted recently, you find out what breaks when you increase things by an order of magnitude.

Basically, the stitching software, Kolor Autopano Giga, was basically inoperable with this size data set. They scolded me for not having told them about this shoot beforehand. They told me that they know about the issues but other things are taking precedence in the development of the software. Stitching a world record amount of images is, by definition, an edge case. So they weren't really able to help me.

Stitching ended up taking nearly 4 months when we thought it would take about 4 weeks. These 4 months were spent working until 3 or 4am many nights of the week. Deadlines slipped. I suffered. My family suffered. After 6 weeks of work I had accomplished nearly nothing and started to panic. I just had to keep on pushing....

In the end, we had to set a delivery date for the client. This required me to leave a few mistakes in the image that I would have liked to fix. However keep in mind that some areas of bad alignment on a normal image might take 30 minutes to fix, but with this size project in the software, it took A WEEK to fix. This kind of work is extremely demoralizing and there isn't much to be learned from it either.

In the end, the image is finished. As they say "you never finish, you only stop!". I'll probably make a few more fixes, later. For right now I need to decompress for a while.

So that is some background on how the image was created. It's not perfect, but overall it is much better than I expected. Shipping it was a terrible, brutal grind that I hope to never experience again. But it's done now and that feels pretty sweet.

I'm typing this on the bus home from the airport after being in London for a tv show where they announced the image. That was fun. But the best feeling is knowing that the thing is finished and shipped, and if I ever have to do a similar job again I will hopefully learn from the mistakes made on this one and not have such a terrible grind again.

I'm happy to answer any questions about the image that I didn't answer here. thank you!