What settings cause the background to appear less blurry or stretched?
Since we don’t know what picture you are going to use in the background, there sometimes need to be some adjustments to get the effect you want for the background. If you keep the background distance to low values like 20, not 50 or more, the background is flatter and stretched less. Using a lower setting for the camera angle causes more linear movement in the background. Also, if the foreground picture is in portrait orientation, the background will be distorted less if it is in the same orientation. Using a person’s photo in portrait mode, and a background in landscape mode causes the background to have to be changed in aspect ratio (since both have to be in the same final picture).