I don't think so. Intuitively, DOF should depend on the aperture width and
the real to image ratio. That's why subminiature and digitals have so much,
and LF (8x10, 11x14") have so little at the same apertures, even tho the
film image is enlarged afterwards.
Maybe I'll play with the DOF calculator...
tOM
On Sunday, December 30, 2001 at 9:43, John Robison
<olympus@xxxxxxxxxxxxxxx>
wrote re "Re: [OM] OM macro / closeups vs medium format / T" saying:
>
> --- Tom@xxxxxxxxxxxxx wrote:
> > On Sunday, December 30, 2001 at 3:48, John Robison
> > > > She/He's fooling himself. You get the same depth
> > of
> > > > field with a given
> > > > focal length, aperture, and image enlargement..
> > > >
> > > > tOM
> > > DOF's really the same for a given aperture and
> > > Image/Object ratio regardless of focal length.
> > John Robison
> >
> > I think you mean aperture in mm rather than f/ratio?
> >
> > tOM
> Hi Tom (and John Lind) Please pardon my 4AM reply, I
> woke up at 2:30 and coulden't get back to sleep. Went
> back to bed, caught a few more Z's and now have my 2nd
> cup of coffee in hand(in a Olympus mug,no less). What
> I tried to say was that if you set up your OM to
> photograph say a head and shoulders portrait with a
> leafy background and as an expirement you first
> mounted your 24mm, set apature at f4 and placed camera
> 2 and 1/2 feet from subject, exposed frame 1, now
> mount the 50mm at f4 at 5ft from subject, frame 2, now
> mount your 100mm at f4 at 10ft from subject. frame 3,
> woulden't all 3 frames have about the same DOF and the
> background have about the same degree of fuzzyness? Or
> am I all wet? About the math, I am a MMM that Math
> Mental Miget, I can visualize the why of DOF but when
> you guys start talking log and cos and things like
> that your are way over my head<G>. And John L., love
> your site, it's a standard place of reference I go to
> often. John Robison
------- Quidquid latine dictum sit, altum viditur -----------------
,__@ Tom A. Trottier +1 613 860-6633 fax:231-6115
_-\_<, 758 Albert St.,Ottawa ON Canada K1R 7V8
(*)/'(*) ICQ:57647974 Tom@xxxxxxxxxxxxx N45.412 W75.714
---------------------------------------------------------------------
Laws are the spider's webs which,
if anything small falls into them they ensnare it,
but large things break through and escape.
--Solon, statesman (c.638-c558 BCE)
I believe there are more instances of the abridgment of the rights of
the people by the gradual and silent encroachments of those in
power than by violent and sudden usurpations. -James Madison,
fourth US president (1751-1836)
< This message was delivered via the Olympus Mailing List >
< For questions, mailto:owner-olympus@xxxxxxxxxxxxxxx >
< Web Page: http://Zuiko.sls.bc.ca/swright/olympuslist.html >
|