Shame about the dust.
rfsIII: The only criticism I have is that you shouldn't test lens distortion by taking pictures in a city that's more than 2,000 years old.
So many of London's buildings are beyond ancient and the rest are built atop the unsteady debris of thousands of years of human occupation; I cannot imagine that there is a straight wall or level floor anywhere within that venerable metropolis.
What you see as evidence of "severe" barrel distortion is more likely just a medieval wall bowed outward by the relentless forces of gravity and time.
Too big, and too heavy!
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