After a few seconds of shooting,

You can try to see if the focus prompt point in the lower left corner of the viewfinder lights up when you half press the shutter (you can also set the focus prompt tone). If it comes on, press the shutter again to see if you can shoot it immediately. SLR cameras can only press the shutter after focusing in order to prevent focusing errors. If the ambient light is insufficient, the lens aperture is small (less than F/5.6-8) or the contrast of the subject is weak, autofocus will be slow. If you don't have the habit of focusing in advance by pressing the shutter half-way, the phenomenon of "bellows pulling" will also appear in autofocus. If you can't focus, shooting will be delayed. If you use a small aperture lens and a 2-fold magnifying glass, the aperture will be reduced by two levels, and auto-focusing will be more difficult, and even manual focusing can only be used.

In addition, the center of D8 10 is sensitive to the focus, which supports F/8 lens autofocus. Many photographers are used to the central single-point autofocus, focusing with the central focus when the shutter is half pressed, and then re-framing after focusing. This shooting method has a high success rate of focusing.