[To Keith McManus, who sometimes sends me email
without the courtesy of using the correct return
address, often with inane and inaccurate statements
that he is too reluctant to offer publicly in these
NGs...;-]

>The depth-of-field remains the same for all focal lengths, no matter
>what the format.
>"W. Keith McManus"

That is not correct without equalizing the final image size,
the angle of view, and the aperture - and even then the many
ways in which DOF is affected in the real world precludes
this from being strictly true much of the time (see my first
post, above, for more...).