I took some sample photos using my Nikon D5600 camera with Nikon f/1.8D lens. I had to set the focus manually since this lens doesn't provide AF with my camera.
My Question: The album of my sample pics (just 3 pics) is present at this Flickr Link.
In this Pic (Short focal length = 4.22m), the girl is blurred along with the background. This makes sense to me because the focal point was set somewhere in front of the girl and hence all the things behind that focus point were blurred.
But in these two pics (Long distance focus point = 21.13m), I guess that I set the focal length to infinity (or near infinity). The girl was standing at a distance of around 10-15 feets from me. Now my question is, why everything behind the girl is focused? Why are the things beyond a distance of 21.13m are also focussed?
Last Question; I tried so much but I couldn't find any focus point to bring the girl into focus when she was standing at a distance of 10-15 feets, is this normal or did I made some mistake?
PS: I was shooting at f/1.8.