This makes a lot of sense: our phones use a lens to make the images, which is why we observe focal effects such as blurriness. With a pinhole, there focus level appears to be more consistent, but there is a lot of detail the lens gets that is missing from the pinhole
ttalati
So is the idea that at the perfect focal length, all the rays cast from a certain point converge onto the focal plane on the other side of the lens. Like the picture here only shows rays cast from near the face of the person, but if we were viewing rays from the shoes of the person for instance would the result be convergence on the shoes. I guess I am just confused about how this stuff works for other points rather than the examples only showing one point.
rcorona
To try answering @ttalati's question, my understanding is that the focal length is defined in the axis perpendicular to the lens.
So in this cartoon, I think that because the man in essence is standing on a plane that's parallel to the lens, then every point of the man's image will be at the focal length (i.e from head to toe).
My intuitive understanding is that as the sensor for the image moves away from the focal point in either direction, light rays originating from the same point in the object will no longer converge to the same point, but will instead become more scattered as the distance from the focal point increases, causing blurring.
This makes a lot of sense: our phones use a lens to make the images, which is why we observe focal effects such as blurriness. With a pinhole, there focus level appears to be more consistent, but there is a lot of detail the lens gets that is missing from the pinhole
So is the idea that at the perfect focal length, all the rays cast from a certain point converge onto the focal plane on the other side of the lens. Like the picture here only shows rays cast from near the face of the person, but if we were viewing rays from the shoes of the person for instance would the result be convergence on the shoes. I guess I am just confused about how this stuff works for other points rather than the examples only showing one point.
To try answering @ttalati's question, my understanding is that the focal length is defined in the axis perpendicular to the lens.
So in this cartoon, I think that because the man in essence is standing on a plane that's parallel to the lens, then every point of the man's image will be at the focal length (i.e from head to toe).
My intuitive understanding is that as the sensor for the image moves away from the focal point in either direction, light rays originating from the same point in the object will no longer converge to the same point, but will instead become more scattered as the distance from the focal point increases, causing blurring.