Re: Large formad drawback?

Thom wrote:
> 
> On Mon, 24 Nov 2003 23:00:51 -0800, Crownfield <[EMAIL PROTECTED]>
> wrote:
> 
> >geo wrote:
> >>
> >> "Collin Brendemuehl" <[EMAIL PROTECTED]> wrote in message
> >> news:[EMAIL PROTECTED]
> >> > DOF is controlled primarily by 2 things --
> >> > focal length and aperture opening size --
> >> > and secondarily, less significantly by
> >> > optical design.
> >> >
> >>
> >> Focal length does not change depth of field. A 35mm lens has the same depth
> >> of field as a 400mm lens at any given aperture.
> >
> >not everyone agrees with you. for example,
> >http://www.isorainbow.com/tech/depth.html
> I went to the website and they are totally wrong.  I went thru Brooks
> and we were not only told the same thing we had an assignment to prove
> it.

not everyone agrees with you. for example:

http://www.dvinfo.net/articles/optics/dofskinny.php
http://medfmt.8k.com/mf/hyperfocal.html
http://ccollege.hccs.cc.tx.us/instru/photog/stdpprs/vad1457.html
http://www.trenholm.org/hmmerk/DOFR.html
http://homepage.mac.com/bugbob/photo-tips/hyperfocal-distance.html
http://azone.clubsnap.org/insectguide/page02.html
http://tangentsoft.net/fcalc/help/Hyperfocal.htm
http://www.vanwalree.com/optics/dofderivation.html
http://www.invisiblematrix.net/photography/tutorial.php?tutorial_file=dof.php

there were more, but I got tired.

> 
> The only exception is that Australian designed movie lens where
> everything is in focus but it is so weird and far out of what we're
> talking about its not relivant.
> 
> If you take an obect say 25mm's tall and photography it with a 17mm,
> 28mm, 85mm and 250mm lens all at F8 (i.e.) and the image size on the
> film is 25mm the depth of field will be the same for all lenses.  Wide
> angles lens give the illusion of greater dpeth of field.
> 
> THOM
> >
> >> Wide angle lenses have
> >> greater APPARENT depth of field because distant objects are smaller and the
> >> lack of sharpness is less obvious but if you were to measure it DOF is
> >> exactly the same.
> >>
> >> Natural Light Black and White Photography
> >> http://mysite.verizon.net/geost/
> >> -George-