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Re: [Rollei] Re: Rollei panorama head
- Subject: Re: [Rollei] Re: Rollei panorama head
- From: "kevin" <logik >
- Date: Sat, 10 May 2003 20:01:22 -0700
- References: <20030510200924.54562.qmail >
I agree with Carlos on this. I learn so much from everyone on this list.
It's why I subscribed! Thanks everyone for your wonderful knowledge, it
keeps people like myself inspired.
- ----- Original Message -----
From: "Carlos Manuel Freaza" <cmfreaza
Sent: Saturday, May 10, 2003 1:09 PM
Subject: Re: [Rollei] Re: Rollei panorama head
> Mr. Knoppow, I wrote and I write that I always learn
> with your technical answers. Thank you very much.
> All the best
> --- Richard Knoppow <dickburk > escribió:
> > ----- Original Message -----
> > From: "Eric Goldstein" <egoldste >
> > To: <rollei
> > Sent: Saturday, May 10, 2003 9:07 AM
> > Subject: [Rollei] Re: Rollei panorama head
> > > Eric Goldstein <egoldste > escribió:
> > >
> > > >> I too am a user of the rollei pan head... I
> > find it
> > > >> tends to work better
> > > >> with the 75 mm lens on my 'cord III than the 80
> > mm
> > > >> on the 2.8C; the frames
> > > >> seem to match a bit closer...
> > > >>
> > > >> Does anyone have any other experience with this
> > > >> accessory?
> > >
> > >
> > > Carlos Manuel Freaza:
> > >
> > > > About the frames a bit closer, I think it
> > depends
> > > > subject and distance to subject.
> > >
> > >
> > > Good point Carlos. I guess I am assuming the most
> > users
> > are shooting distant
> > > objects horizon line is usually
> > present
> > somewhere, as in
> > > your shot...
> > >
> > >
> > > Eric Goldstein
> > >
> > One problem I've found with shooting panoramas
> > with the
> > Rollei head or just in general with multiple images
> > from a
> > standard camera is the mismatch at the edges of the
> > pictures
> > due to the "distortion" from the rectilinear
> > geometry of the
> > lens.
> > If you photograph an array of spherical objects,
> > say golf
> > balls, you will find those at the corners of the
> > picture are
> > egg shaped. If the picture is viewed from the
> > correct
> > distance with one eye, the golf balls will look
> > round again.
> > This is because of the diminishing perspective when
> > viewing.
> > This is also the cause of the "distortion" when
> > using wide
> > angle lenses. It really isn't distortion, it comes
> > from
> > viewing from the wrong distance. If an array of
> > circles on a
> > flat surface is photogrphed they will be reproduced
> > as
> > circles since in both life and when viewing the
> > photo the
> > perspective will make them appear somewhat
> > eliptical. This
> > is why the "distortion" does not have any effect
> > when
> > enlarging or projecting.
> > The effect when combining photos for a panorama is
> > to
> > distort the shape and angles of intersection at the
> > edges.
> > The effect could be eliminated by projecting onto
> > paper held
> > on a spherical surface or by using a special
> > corrector lens
> > giving the same effect. This correction is easily
> > done using
> > a computer but not easy for photographic printing.
> > I am _very_ suspicious that the beautiful examples
> > of
> > panoramic photos shown in the Rollei instruction
> > manual were
> > actually photographed with a rotating panoramic
> > camera, they
> > match too perfectly.
> > The mismatch can be seen in Carlos's photo but is
> > not too
> > obvious because of the subject matter and also the
> > outstanding job of matching the tonal rendition of
> > the
> > sections. It can, however, be seen in the railing.
> > As for the use with a 75mm vs: an 80mm lens, the
> > 75mm
> > might be better because of larger overlap but it may
> > also be
> > that the panoram head turns closer to the rear nodal
> > point
> > of the shorter lens. I suspect error from any
> > mis-match here
> > is very slight, if it exists at all.
> > Note, that since the lens moves with regard to the
> > swivel
> > point of the adaptor when the distance of focus is
> > changed
> > that the match with the nodal point will not be as
> > good for
> > close objects as for distant ones. Also, the overlap
> > will be
> > less since the effective viewing angle of the lens
> > is less
> > with close objects (except for front element
> > focussing
> > lenses or when a close up diopter attachment is
> > used).
> > This is a remarkably good example of a panoram
> > photo.
> > ---
> > Richard Knoppow
> > Los Angeles, CA, USA
> > dickburk
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End of Rollei Users list digest V12 #76