Thermal imaging cameras are incredibly expensive and most do not even go beyond 640 x 360 resolution. I wonder which camera was used here

Author here. The camera was a Seek RevealPro which has 320x240 resolution. The thermal data in the panoramas are stitched together from raw data exported by the camera and represented as color (hue+saturation, as per scale in upper right, represents temperature data).

The brightness channel is piecewise-linearly combined with a corresponding visual image taken with a regular SLR to provide a visual reference of what you're looking at.

right in the article, "Since I wanted to image wide-angle landscapes in high resolution, and my thermal camera’s field of view was only about 24 degrees, I had to put together a DIY rig to panoramically scan the scene. I also simultaneously shot a black-and-white photo with a regular camera and a wide-angle lens for comparison. I then wrote my own program to color the black-and-white photograph with the actual thermal data, using a false-color scale which you see in the upper-right corner of every image."

I don't think TJ was being snarky or anything...

yep, not being snarky, else I would have used nasty language like you did *hint*
I figured he missed the info in the latter part of the paragraph in which it was contained.
I wasn't sure if he thought the actual image was from a thermal camera or not (since he mentioned the resolution and may have been perplexed/wondering if there was a higher res thermal camera available).
Take your cursing elsewhere.

Your full of crap, and trying to back track. Who else said anything bad in the first 4 words.

And the photos are indeed amazing

Thank you for the information - at work we have a Fluke thermal imaging camera, I think with a 640 x 480 resolution. I might try out some of the panoramic stitching later - though I have to think on how to do the movement of the camera since it would have to be precise

Much appreciated

There are some low cost (low res) thermal cameras on aliexpress for $88. The future is here!

Nice article