A:AnswerThis really depends on the style you want the picture to have. I wouldn’t recommend filling the frame with people unless they are directly in the middle as the edges tend to distort your subjects along the borders. Kind of like a fish eye.
A:AnswerNot sure what you are asking. You would take off the 75-300 lens and put this one on instead. The lenses cannot be "stacked". This will give you a much wider view. Wide angle lens.
