What is the aperture range of the lens if you want to take a portrait in the distance? The camera is Sony a7.

The farther the distance, the shallower the depth of field. Therefore, if you shoot a long-distance portrait (provided the focal length is long enough), you can still get a good background blur effect even if you reduce the aperture by several steps. As for the aperture range, it depends on the lens. If the f/2.8 is unchanged, you can choose to turn it on according to the distance, or you can receive f/4-5.6 from a long distance, because the depth of field is too shallow to focus easily. If the maximum aperture at the telephoto end is f/5.6 (at this time, the focal length is usually more than 200mm), the background blur effect can also be obtained by directly receiving f/8 (the image quality will be reduced when it is fully opened, so turn it off).