It is par focal, however, you must focus at a longer focal length and then go backwards. The way
you mentioned isn't how it works, quite the opposite actually.
I do not understand , why all the time I have to take focus at a longer focal length . Why I can not start from 80 and zoom in to 200 ? Okay I am in church , newlyweds front of me I want to zoom in , and I CAN NOT DO IT . Why , because I lose focus .
Sorry guys I am new with camcorder which let me play with many lens . Is all zoom lens behave like this ? . Do I have to always take focus at a longer focal ? It does no matter what brand of lens I use ?