What do you think is the most difficult part about using aperture and shutter speed?

Aperture is a veryyy sensitive thing, and you have to be very careful, and you have to be sure of the right size in order too get the best picture quality. Shutter speed too. It depends on how fast your subject is moving, (action shot, portrait, etc.) and what kind of picture you want, with a bit of blur or clear as day. You have to be exact with the numbers, and if you are not, you could miss a great photo oppurtunity.

The linear perspective changed the quality of art because it gave art a sense of reality. it gave the illusion that the background and surroundings were actually close and/or far and a sense of depth. linear perspective change the quality of art following its birth the renaissance period as they want the art to be more realistic and they believe one way to achieve it is to use the method of linear perspective. it uses the principle of math to realistically portray space and depth in art.