> -----Original Message-----
> From: Chris Brogden [mailto:[EMAIL PROTECTED]
> Sent: Thursday, February 27, 2003 1:34 PM
> To: [EMAIL PROTECTED]
> Subject: RE: The flood gates open....
>
>
> On Thu, 27 Feb 2003, J. C. O'Connell wrote:
>
> > > Not true. Using a film camera, take a picture of a person with a
> > > telephoto lens so that all you can see is their head and
> shoulders. Then
> > > put a wide angle lens on, and walk closer to the subject
> until you can see
> > > just their head and shoulders. Now your subject is the same
> size as it
> > > was with the telephoto lens, but you have much more DOF.
> >
> > This is false. If the reproduction ratio remains the same like
> > youre describing above the DOF is also the same for
> > a given f-stop, regardless of focal length...
>
> ...only if the photographer stays in the same place. If you stand in the
> same place and take shots with different focal lengths, the DOF is the
> same (you're essentially just cropping). But if you *change position*
> (like I said above) to keep the subject size the same while using a
> different focal length, then your DOF will change, too. DOF depends on
> focal length and aperture, as you say, but also on subject distance.
>
> chris
>
Wrong, DOF depend solely on on magnification and f-stop. If you shoot
from far with a tele or close with a wide it doesnt matter what lens
you use the DOF will be the same as long as the magnification is the same.
