How to calculate the angle of a PIR and which camera to use

[julianorodrigues0316]

Hi people

How do I calculate an angle of 100 ° Degree. I have a ladder (photo attached) and I want to place a sensor PIR movement Hc-sr505 on the emergency lamp (it is green in the attachment) and the sensor has a 100 ° Degree angle, how do i see if those 100 ° takes the entire ladder?

Another question, here on the website, helped me, because I wanted ESP32-cam to film my patio, they gave me the idea to buy a Raspberry, and I bought one, Raspberry Pi 4 Model b, with 2Gb, I want to stream it if I notice movement, my question is, which camera to buy? I thought of the one I show down there, in the annex, however it has 130 degrees and 65 degrees. The higher the degree, the smaller the area the camera takes and the better the quality, and the lower the degree, the larger the area the camera takes and the worse the quality, however, for this patio, which would be better?
One of 130 Degrees, would you take the whole patio (photo of the patio attached)? Or the 65Graus already takes the whole patio? You can "measure" how much each "degree" ie 130 and / 65 degrees picks up?