Atmospheric refraction, due to the different temperature/altitude profile in the atmosphere at different times of day...makes distant mountains appear taller or shorter.

The attached photo is a comparison of what I shot yesterday afternoon and this morning. The camera was set up within inches of the same location for both shots, and those mountains are between 50 and 120 miles away...so I'm saying that any parallax effect from camera location is essentially zero.

I have annotated with arrows where it's easy to make a comparison of how the near and far ridge lines overlap differently in the two photos.

This is a follow up to:
universeodon.com/@KrajciTom/11

Imagine the care that was needed to conduct surveys before the GPS/GNSS era:
explorersweb.com/the-five-men-

"The Great Theodolite built by Troughton & Simms in London stood nearly 1.5m high, had a horizontal circle one meter in diameter, and could read angles to a single second of arc. Moving it required 30 porters and sometimes elephants."

"The reduction of Nicolson’s observations was a colossal task. Each ray from each station had to be corrected for instrumental error, for temperature and pressure, and for the curvature of the Earth. Above all, they needed to correct for atmospheric refraction, which at those distances could amount to six or seven minutes of arc and change from hour to hour."

A comparison of two photos of the same distant mountain ridges. Arrows show places where the ridgelines overlap in different ways in the two photos. The top photo is grayscale, the bottom one is color.The great theodolite. Photo: Survey of India Archives
0

If you have a fediverse account, you can quote this note from your own instance. Search https://universeodon.com/users/KrajciTom/statuses/115674566844432767 on your instance and quote it. (Note that quoting is not supported in Mastodon.)