Hey guys, I’m in need of some assistance! 8D

I’m trying to better understand perspective, and there are quite a few holes in my comprehension of the mechanics. Currently I’m looking for a tutorial that can explain and identify perspective in a natural environment. I need a guide that can:

1. Help me to identify what perspective an image is, concerning nature.
2. Show me how to effectively map them, in simple ways if possible, when trying to create a believable perspective in nature.
3. Determine how to find a horizon when one cannot be seen, unless knowing where the horizon is has no impact on a closed environment.
4. Tell me how to define, concerning perspective, a scene with only a horizon and skyline, and no other objects, or whether it is even considered a perspective. (This one is unimportant, I’m only curious.)

This tutorial would help me to understand how you would determine the perspective of these photos, for example:

[1] ○ [2] ○ [3]

To be clear, I’m not looking for anything with buildings or cubes, where one can identify the directions of objects clearly. Does that make sense? I need a way to identify perspective in a scene w/o any telling direction markers, or when the horizon is hidden. I already have an understanding of how to find perspective with buildings & roads/receding lines, and also know how to create an image with these things.

If you want to try and explain these questions, that’s fine also. :) Although I’m looking for thorough hows and whys, and lots of visual aids.

Anyhoo, if you happen to know of one that can help me with this I’d be so grateful! Thanks in advance! :D