Hi. I was wondering if somebody could give me some pointers as to how to resolve some perspective problems. I should probably mention that I do know the general stuff, read at least 3-4 perspective books, and all the video tutorials on the subject I could get my hands on, however I keep getting stuck in practical problems like this whenever I don't do a very square urban scene/start with sketching freely, so I would highly appreciate some practical advice. What I'm looking to do is to find out the correct scale of items in the scene, based on the character at the balcony 1). So for the people in the foreground 2) and especially I'm stuck at figuring out what the scale of the statue/plaza in the center is. I know the horizon passes through all pictures at the same high, and a couple of times I thought i had figured out a way to measure things by going to the horizon... however I ended up with results that seem wrong to me, and it seems to me arbitrary as to if I have a figure to which point on the horizon i go to to find an intermediary height which then using that reference point to come back to the desired location. So for example I would take figure 1) and take it towards the vanishing point of the castle wall on the right. Then I would translate it would and project that to the place i want figure 2), and so I ended up with that figure... however if i go to a different vanishing point i get a different height.
I must be missing something obvious and I would really appreciate a point in the right direction. Another question that I would appreciate a hint is something that confuses my intuition: I know that in a 2 point perspective I should be able to move heights up and down, however intuitively i would feel that lets say i could find the height of statue 3) in terms of human heights, and i put a human at it's top, intuitively if i lower him to the base i would think he'd be smaller 'cause he's further away than if he is on the horizon line.
Thank you very much for your patience and hopefully help.
PS: I apologize if I posted this in the wrong category: I looked around and searched but I couldn't find a better place where I could ask such a question.