Top view of the lens - yes - it's that large. Aperture is 112mm at f/4. I use mostly f/5.6 for exposures. A KR 1.5 filter is used in with the 400 lens in the 67mm size in the rear door. The lens allows the camera body to be swivelled for portrait or landscape. Every possible measure taken to prevent flexure. A whole different ballgame when going for 90 minutes.