Archived posting to the Leica Users Group, 2000/11/10
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]Brougham wrote: > > Mark Rabiner <mark@rabiner.cncoffice.com> wrote: > > > If you fill the top to bottom of the chair with a 28mm it should give > > you just as much front to back dof as when you pull way back across > > the street and fill the chair top to bottom with a 90mm lens. > > > > But it doesn't'. > > Why should it be the same? DOF is based on aperture and distance from > the lens. > > The larger the aperture opening, the larger the circles of confusion. > Less DOF. > > The further from the lens, the less relative change in the size of the > circles of confusion as you move the same absolute distance. More > DOF. > I think it's based on magnification and aperture. Mark rabiner