I have actually found that beginners do not even know that there is such a thing as depth of field.
There are many who have had dslr's for years and do not understand DOF. I am currently on a family holiday in Turkey in a family holiday village. Without exaggeration I must of had 8 people see me with my camera and ask me to take a couple of photo'S of their family and have handed me their dslr's or bridge cameras. I was surprised to see that every camera was on AUTO setting, Out of interest I questioned a few as to trying the other settings such as aperture setting or manual setting, one guy with a canon 650d said he does not understand what they do and why bother when he is happy with the results he gets in auto mode. This was also the response I got with a gentleman with a Fuji bridge camera.
I know also many in my home town including my brother with decent cameras and who have owned them for some time who are quiet happy to leave the camera in auto. How would you start or where would you start to tell them the benefits of changing their style or give them a little knowledge to improve their photography.????

