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NP 16mm and 70-200mm

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  • AYRTON
    Hi guys good day please does someone does know the location of the NP on the below lenses Nikkor 16mm fisheye Nikkor 70-200 mm F:2.8 Thanks a lot best AYRTON
    Message 1 of 14 , Sep 4, 2010
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      Hi guys
      good day


      please does someone does know the location of the NP on the below lenses

      Nikkor 16mm fisheye

      Nikkor 70-200 mm F:2.8

      Thanks a lot

      best
      AYRTON

      --
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      | T O N |
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      twitter.com/ayrton360


      [Non-text portions of this message have been removed]
    • Michel Thoby
      Hi Ayrton, Pierre Toscani wrote some excellent articles with awesome illustrations. Well, I know that you can read in French:) About the Nikkor 16 mm Fisheye.
      Message 2 of 14 , Sep 5, 2010
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        Hi Ayrton,

        Pierre Toscani wrote some excellent articles with awesome illustrations. Well, I know that you can read in French:)

        About the Nikkor 16 mm Fisheye.
        On his page about Nikon fisheyes:
        http://www.pierretoscani.com/echo_fisheyes.html#fisheye3
        You may look at figure 14
        Pierre Toscani has calculated and ray-traced the movement of the entrance pupil (fig 12 and 13): As there is probably no pertinent fixed point for wide angle lenses (including fisheyes: cf on fig 8, 9 and 16), therefore he uses the word LPP (Least Parallax Point = "Point de Moindre Parallaxe") in lieu of NPP to better name that elusive point. That's a practice that I had suggested earlier on this list:)

        About the Nikkor 70-200 mm f2.8
        You do not specify which focal length you need the information for. Anyhow you shall find an answer for both the two extreme zoom settings here:
        http://www.pierretoscani.com/echo_pupilles.html#pupilles6
        "P.E". means Entrance Pupil ("Pupille d'Entrée") on the drawings; That's (on the axis) were the "NPP" is "practically" located. You can observe the large longitudinal movement of the Pupil when zooming the objective: being located near the middle of it at 70mm, it's shifted way behind the whole lens at 200mm... in a fortuitous coincidence with the image plane!

        Bon jour,

        Michel


        Le 5 sept. 2010 à 07:00, AYRTON a écrit :

        > Hi guys
        > good day
        >
        > please does someone does know the location of the NP on the below lenses
        >
        > Nikkor 16mm fisheye
        >
        > Nikkor 70-200 mm F:2.8
        >
        > Thanks a lot
        >
        > best
        > AYRTON



        [Non-text portions of this message have been removed]
      • AYRTON
        Michel bonjour I can only say Merci beaucoup mon ami This is a great list a place to make and find friends ! Thanks for helping me out the papers are perfect,
        Message 3 of 14 , Sep 5, 2010
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          Michel
          bonjour

          I can only say
          Merci beaucoup mon ami

          This is a great list a place to make and find friends !
          Thanks for helping me out
          the papers are perfect, full of explanations

          Cheers from Rio
          AYRTON


          On Sun, Sep 5, 2010 at 5:08 AM, Michel Thoby <thobymichel@...> wrote:

          > Hi Ayrton,
          >
          > Pierre Toscani wrote some excellent articles with awesome illustrations.
          > Well, I know that you can read in French:)
          >
          > About the Nikkor 16 mm Fisheye.
          > On his page about Nikon fisheyes:
          > http://www.pierretoscani.com/echo_fisheyes.html#fisheye3
          > You may look at figure 14
          > Pierre Toscani has calculated and ray-traced the movement of the entrance
          > pupil (fig 12 and 13): As there is probably no pertinent fixed point for
          > wide angle lenses (including fisheyes: cf on fig 8, 9 and 16), therefore he
          > uses the word LPP (Least Parallax Point = "Point de Moindre Parallaxe") in
          > lieu of NPP to better name that elusive point. That's a practice that I had
          > suggested earlier on this list:)
          >
          > About the Nikkor 70-200 mm f2.8
          > You do not specify which focal length you need the information for. Anyhow
          > you shall find an answer for both the two extreme zoom settings here:
          > http://www.pierretoscani.com/echo_pupilles.html#pupilles6
          > "P.E". means Entrance Pupil ("Pupille d'Entrée") on the drawings; That's
          > (on the axis) were the "NPP" is "practically" located. You can observe the
          > large longitudinal movement of the Pupil when zooming the objective: being
          > located near the middle of it at 70mm, it's shifted way behind the whole
          > lens at 200mm... in a fortuitous coincidence with the image plane!
          >
          > Bon jour,
          >
          > Michel
          >
          >
          > Le 5 sept. 2010 à 07:00, AYRTON a écrit :
          >
          > > Hi guys
          > > good day
          > >
          > > please does someone does know the location of the NP on the below lenses
          > >
          > > Nikkor 16mm fisheye
          > >
          > > Nikkor 70-200 mm F:2.8
          > >
          > > Thanks a lot
          > >
          > > best
          > > AYRTON
          >
          >
          >
          > [Non-text portions of this message have been removed]
          >
          >
          >
          > ------------------------------------
          >
          > --
          >
          >
          >
          >


          --
          ------------
          | A Y R |
          | T O N |
          ------------
          + 55 21 9982 6313 - RIO
          + 55 11 3717 5131 - SP
          http://ayrton360.com
          twitter.com/ayrton360


          [Non-text portions of this message have been removed]
        • Scott Highton
          Ayrton, The NP or nodal point is the wrong term to use. I think you re actually looking for the Entrance Pupil, or no-parallax point about which to rotate
          Message 4 of 14 , Sep 6, 2010
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            Ayrton,

            The "NP" or nodal point is the wrong term to use. I think you're
            actually looking for the Entrance Pupil, or no-parallax point about
            which to rotate the lens for stitched panoramic photography. ("Nodal
            Point" was mistakenly used to describe this position in a lens by
            Apple during their documentation of early QTVR photography, and
            unfortunately it has been misused by many since then.)

            For a zoom lens such as the 70-200mm, the entrance pupil location will
            vary with the chosen focal length. However, at longer focal lengths,
            precise alignment of the entrance pupil over the rotation axis is not
            so critical, because most subjects are not close enough to the lens to
            result in noticeable parallax differences while panning. It is far
            more critical to align properly with ultra wide lenses where subjects
            are often quite close.

            For the Nikkor 16mm f/2.8AF lens (and other Nikkors), you might want
            to check out the Technical Note on "Choosing a Lens for Panoramic VR"
            at the Virtual Reality Photography web site: http://www.vrphotography.com/data/pages/techtutorials/technotes/panolenschoice.html

            At the bottom of the page, you'll find photo illustrations showing the
            physical position of the entrance pupils of several commonly used
            Nikkor ultra wide and fisheye lenses, including the 16mm.

            Regards,



            Scott

            Scott Highton
            Author, Virtual Reality Photography
            Web: http://www.vrphotography.com/bookpromo.html



            [Non-text portions of this message have been removed]
          • Mark D. Fink
            Is it generally true that the NPP on telephoto lenses is well behind the front element, in some cases, (such as the Nikkor AF-S VR 300 mm), well behind the
            Message 5 of 14 , Sep 7, 2010
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              Is it generally true that the NPP on telephoto lenses is well behind the
              front element, in some cases, (such as the Nikkor AF-S VR 300 mm), well
              behind the film plane? Are there any exceptions to this that anyone is aware
              of?

              Thanks,

              Mark

              www.northernlight.net
              www.virtual-travels.com
              www.pinnacle-vr.com

              > -----Original Message-----
              > From: PanoToolsNG@yahoogroups.com [mailto:PanoToolsNG@yahoogroups.com] On
              > Behalf Of Michel Thoby
              > Sent: Sunday, September 05, 2010 4:09 AM
              > To: PanoToolsNG@yahoogroups.com
              > Subject: Re: [PanoToolsNG] NP 16mm and 70-200mm
              >
              > Hi Ayrton,
              >
              > Pierre Toscani wrote some excellent articles with awesome illustrations.
              > Well, I know that you can read in French:)
              >
              > About the Nikkor 16 mm Fisheye.
              > On his page about Nikon fisheyes:
              > http://www.pierretoscani.com/echo_fisheyes.html#fisheye3
              > You may look at figure 14
              > Pierre Toscani has calculated and ray-traced the movement of the entrance
              > pupil (fig 12 and 13): As there is probably no pertinent fixed point for
              > wide angle lenses (including fisheyes: cf on fig 8, 9 and 16), therefore
              > he uses the word LPP (Least Parallax Point = "Point de Moindre Parallaxe")
              > in lieu of NPP to better name that elusive point. That's a practice that I
              > had suggested earlier on this list:)
              >
              > About the Nikkor 70-200 mm f2.8
              > You do not specify which focal length you need the information for. Anyhow
              > you shall find an answer for both the two extreme zoom settings here:
              > http://www.pierretoscani.com/echo_pupilles.html#pupilles6
              > "P.E". means Entrance Pupil ("Pupille d'Entrée") on the drawings; That's
              > (on the axis) were the "NPP" is "practically" located. You can observe the
              > large longitudinal movement of the Pupil when zooming the objective: being
              > located near the middle of it at 70mm, it's shifted way behind the whole
              > lens at 200mm... in a fortuitous coincidence with the image plane!
              >
              > Bon jour,
              >
              > Michel
              >
              >
              > Le 5 sept. 2010 à 07:00, AYRTON a écrit :
              >
              > > Hi guys
              > > good day
              > >
              > > please does someone does know the location of the NP on the below lenses
              > >
              > > Nikkor 16mm fisheye
              > >
              > > Nikkor 70-200 mm F:2.8
              > >
              > > Thanks a lot
              > >
              > > best
              > > AYRTON
              >
              >
              >
              > [Non-text portions of this message have been removed]
              >
              >
              >
              > ------------------------------------
              >
              > --
              >
              >
              >
            • AYRTON
              Scott god day Thanks a lot for the links on the fisheyes and the explanations I knew about the NP nomenclaturet, but like you said, it is more common to people
              Message 6 of 14 , Sep 7, 2010
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                Scott
                god day
                Thanks a lot for the links on the fisheyes
                and the explanations

                I knew about the NP nomenclaturet, but like you said, it is more common to
                people to get it fast what I'm talking about :-)
                Sorry I'm not a native english speaker

                On the 70-200 mm I'll be using at 80 mm and my question is where should I
                place the lens "right-perfect-best-point" on my Nodal Ninja NN5


                Thanksssss a lot to you and to Michel who kindly replied to my ask for help
                :-)

                Cheers
                AYRTON



                On Mon, Sep 6, 2010 at 5:04 AM, Scott Highton <scott@...> wrote:

                > Ayrton,
                >
                > The "NP" or nodal point is the wrong term to use. I think you're actually
                > looking for the *Entrance Pupil*, or no-parallax point about which to
                > rotate the lens for stitched panoramic photography. ("Nodal Point" was
                > mistakenly used to describe this position in a lens by Apple during their
                > documentation of early QTVR photography, and unfortunately it has been
                > misused by many since then.)
                >
                > For a zoom lens such as the 70-200mm, the entrance pupil location will vary
                > with the chosen focal length. However, at longer focal lengths, precise
                > alignment of the entrance pupil over the rotation axis is not so critical,
                > because most subjects are not close enough to the lens to result in
                > noticeable parallax differences while panning. It is far more critical to
                > align properly with ultra wide lenses where subjects are often quite close.
                >
                > For the Nikkor 16mm f/2.8AF lens (and other Nikkors), you might want to
                > check out the Technical Note on "Choosing a Lens for Panoramic VR" at the
                > Virtual Reality Photography web site:
                > http://www.vrphotography.com/data/pages/techtutorials/technotes/panolenschoice.html
                >
                > At the bottom of the page, you'll find photo illustrations showing the
                > physical position of the entrance pupils of several commonly used Nikkor
                > ultra wide and fisheye lenses, including the 16mm.
                >
                > Regards,
                >
                >
                >
                > Scott
                >
                > Scott Highton
                > Author, Virtual Reality Photography
                > Web: http://www.vrphotography.com/bookpromo.html
                >
                >


                --
                ------------
                | A Y R |
                | T O N |
                ------------
                + 55 21 9982 6313 - RIO
                + 55 11 3717 5131 - SP
                http://ayrton360.com
                twitter.com/ayrton360


                [Non-text portions of this message have been removed]
              • Scott Highton
                Ayrton, I don t own the Nikkor 70-200mm lens, so I don t have entrance pupil information for it. Your best approach is to figure it out yourself in the
                Message 7 of 14 , Sep 7, 2010
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                  Ayrton,

                  I don't own the Nikkor 70-200mm lens, so I don't have entrance pupil
                  information for it. Your best approach is to figure it out yourself
                  in the viewfinder of your own camera. For information on how to do
                  this (with any lens), see:

                  http://www.vrphotography.com/data/pages/techtutorials/technotes/nodalptalign-tn.html

                  But again, as I wrote earlier, when using longer focal lengths,
                  entrance pupil alignment becomes less critical for stitched panoramic
                  photography because nearest subjects to the camera are generally much
                  farther away than with ultra wide lens shooting, and therefore,
                  parallax is less of a problem. If your nearest subject is more than 8
                  or 10 feet away, the panorama may stitch just fine even without any
                  entrance pupil alignment.

                  I suggest you simply try a test with your camera and lens to see.

                  Regards,



                  Scott Highton
                  Author, Virtual Reality Photography
                  Web: http://www.vrphotography.com





                  -----Original Message-----
                  From: AYRTON
                  Sent: Sep 7, 2010 10:30 AM
                  To: Scott Highton
                  Cc: PanoToolsNG@yahoogroups.com
                  Subject: Re: NP 16mm and 70-200mm

                  Scott
                  god day
                  Thanks a lot for the links on the fisheyes
                  and the explanations

                  I knew about the NP nomenclaturet, but like you said, it is more
                  common to people to get it fast what I'm talking about :-)
                  Sorry I'm not a native english speaker

                  On the 70-200 mm I'll be using at 80 mm and my question is where
                  should I place the lens "right-perfect-best-point" on my Nodal Ninja NN5


                  Thanksssss a lot to you and to Michel who kindly replied to my ask for
                  help :-)

                  Cheers
                  AYRTON

                  [Non-text portions of this message have been removed]
                • AYRTON
                  Thanks again !!!! The problem is that I will only get my hands on the camera and on the lens on the day of a special shooting for a gigaphoto project fpr a
                  Message 8 of 14 , Sep 7, 2010
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                    Thanks again !!!!

                    The problem is that I will only get my hands on the camera and on the lens
                    on the day of a special shooting for a gigaphoto project fpr a Client,
                    shooting a crownd at "night" :-(
                    So it will be no chance to test it before taht day (or night), so just guess
                    to do the better I can :-)

                    Cheers
                    AYRTON



                    On Tue, Sep 7, 2010 at 1:30 PM, Scott Highton <scott@...> wrote:

                    > Ayrton,
                    >
                    > I don't own the Nikkor 70-200mm lens, so I don't have entrance pupil
                    > information for it. Your best approach is to figure it out yourself in the
                    > viewfinder of your own camera. For information on how to do this (with any
                    > lens), see:
                    >
                    >
                    > http://www.vrphotography.com/data/pages/techtutorials/technotes/nodalptalign-tn.html
                    >
                    > But again, as I wrote earlier, when using longer focal lengths, entrance
                    > pupil alignment becomes less critical for stitched panoramic photography
                    > because nearest subjects to the camera are generally much farther away than
                    > with ultra wide lens shooting, and therefore, parallax is less of a problem.
                    > If your nearest subject is more than 8 or 10 feet away, the panorama may
                    > stitch just fine even without any entrance pupil alignment.
                    >
                    > I suggest you simply try a test with your camera and lens to see.
                    >
                    > Regards,
                    >
                    >
                    >
                    > Scott Highton
                    > Author, Virtual Reality Photography
                    > Web: http://www.vrphotography.com
                    >
                    >
                    >
                    >
                    >
                    > -----Original Message-----
                    > From: AYRTON
                    > Sent: Sep 7, 2010 10:30 AM
                    > To: Scott Highton
                    > Cc: PanoToolsNG@yahoogroups.com
                    > Subject: Re: NP 16mm and 70-200mm
                    >
                    > Scott
                    > god day
                    > Thanks a lot for the links on the fisheyes
                    > and the explanations
                    >
                    > I knew about the NP nomenclaturet, but like you said, it is more common to
                    > people to get it fast what I'm talking about :-)
                    > Sorry I'm not a native english speaker
                    >
                    > On the 70-200 mm I'll be using at 80 mm and my question is where should I
                    > place the lens "right-perfect-best-point" on my Nodal Ninja NN5
                    >
                    >
                    > Thanksssss a lot to you and to Michel who kindly replied to my ask for help
                    > :-)
                    >
                    > Cheers
                    > AYRTON
                    >



                    --
                    ------------
                    | A Y R |
                    | T O N |
                    ------------
                    + 55 21 9982 6313 - RIO
                    + 55 11 3717 5131 - SP
                    http://ayrton360.com
                    twitter.com/ayrton360


                    [Non-text portions of this message have been removed]
                  • Christian Bloch
                    so true. In fact I shot some completely handheld panos with that lens, out of a hotel room. Had to shoot out of different windows just to get more of the view,
                    Message 9 of 14 , Sep 7, 2010
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                      so true.

                      In fact I shot some completely handheld panos with that lens, out of a hotel room. Had to shoot out of different windows just to get more of the view, so the nodal point was well 3 meters off, still stitched just fine.

                      Blochi

                      Sent from my iPad

                      On Sep 7, 2010, at 9:30 AM, Scott Highton <scott@...> wrote:

                      > Ayrton,
                      >
                      > I don't own the Nikkor 70-200mm lens, so I don't have entrance pupil
                      > information for it. Your best approach is to figure it out yourself
                      > in the viewfinder of your own camera. For information on how to do
                      > this (with any lens), see:
                      >
                      > http://www.vrphotography.com/data/pages/techtutorials/technotes/nodalptalign-tn.html
                      >
                      > But again, as I wrote earlier, when using longer focal lengths,
                      > entrance pupil alignment becomes less critical for stitched panoramic
                      > photography because nearest subjects to the camera are generally much
                      > farther away than with ultra wide lens shooting, and therefore,
                      > parallax is less of a problem. If your nearest subject is more than 8
                      > or 10 feet away, the panorama may stitch just fine even without any
                      > entrance pupil alignment.
                      >
                      > I suggest you simply try a test with your camera and lens to see.
                      >
                      > Regards,
                      >
                      > Scott Highton
                      > Author, Virtual Reality Photography
                      > Web: http://www.vrphotography.com
                      >
                      > -----Original Message-----
                      > From: AYRTON
                      > Sent: Sep 7, 2010 10:30 AM
                      > To: Scott Highton
                      > Cc: PanoToolsNG@yahoogroups.com
                      > Subject: Re: NP 16mm and 70-200mm
                      >
                      > Scott
                      > god day
                      > Thanks a lot for the links on the fisheyes
                      > and the explanations
                      >
                      > I knew about the NP nomenclaturet, but like you said, it is more
                      > common to people to get it fast what I'm talking about :-)
                      > Sorry I'm not a native english speaker
                      >
                      > On the 70-200 mm I'll be using at 80 mm and my question is where
                      > should I place the lens "right-perfect-best-point" on my Nodal Ninja NN5
                      >
                      > Thanksssss a lot to you and to Michel who kindly replied to my ask for
                      > help :-)
                      >
                      > Cheers
                      > AYRTON
                      >
                      > [Non-text portions of this message have been removed]
                      >
                      >


                      [Non-text portions of this message have been removed]
                    • John Houghton
                      ... Better than guessing is to estimate the entrance pupil position visually. All you have to do is point the eyepiece on the back of the camera towards a
                      Message 10 of 14 , Sep 7, 2010
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                        --- In PanoToolsNG@yahoogroups.com, AYRTON <avi@...> wrote:
                        > So it will be no chance to test it before taht day (or night), so
                        > just guess to do the better I can :-)

                        Better than guessing is to estimate the entrance pupil position visually. All you have to do is point the eyepiece on the back of the camera towards a light source such as a bright window. This will illuminate the entrance pupil, which will appear as a bright disc when you look into the front of the lens. Set an aperture of f/22 and use the depth of field button to stop the lens down. Looking at the entrance pupil with your two eyes should enable you to judge its position to within a few mm. Sliding a finger along the barrel to the same distance will identify the point on the barrel.

                        John
                      • AYRTON
                        ... John, Good Tip !!! Thanks, I ll try that then :-) best AYRTON ... -- ... + 55 21 9982 6313 - RIO + 55 11 3717 5131 - SP http://ayrton360.com
                        Message 11 of 14 , Sep 7, 2010
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                          On Tue, Sep 7, 2010 at 2:32 PM, John Houghton <j.houghton@...>wrote:

                          > Better than guessing is to estimate the entrance pupil position visually.
                          > All you have to do is point the eyepiece on the back of the camera towards
                          > a light source such as a bright window. This will illuminate the entrance
                          > pupil, which will appear as a bright disc when you look into the front of
                          > the lens. Set an aperture of f/22 and use the depth of field button to stop
                          > the lens down. Looking at the entrance pupil with your two eyes should
                          > enable you to judge its position to within a few mm. Sliding a finger along
                          > the barrel to the same distance will identify the point on the barrel.
                          >


                          John,
                          Good Tip !!!

                          Thanks,
                          I'll try that then :-)

                          best
                          AYRTON



                          >
                          > John
                          >
                          >
                          >
                          > ------------------------------------
                          >
                          > --
                          >
                          >
                          >
                          >


                          --
                          ------------
                          | A Y R |
                          | T O N |
                          ------------
                          + 55 21 9982 6313 - RIO
                          + 55 11 3717 5131 - SP
                          http://ayrton360.com
                          twitter.com/ayrton360


                          [Non-text portions of this message have been removed]
                        • Erik Krause
                          ... Since a telephoto lens by definition is shorter than it s own focal length it should be generally true. However, no one stops you putting the limiting
                          Message 12 of 14 , Sep 7, 2010
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                            Am 07.09.2010 13:57, schrieb Mark D. Fink:
                            > Is it generally true that the NPP on telephoto lenses is well behind the
                            > front element, in some cases, (such as the Nikkor AF-S VR 300 mm), well
                            > behind the film plane? Are there any exceptions to this that anyone is aware
                            > of?

                            Since a telephoto lens by definition is shorter than it's own focal
                            length it should be generally true. However, no one stops you putting
                            the limiting aperture in front of the front lens in which case the NPP
                            would be there.

                            But for unmodified telephoto lenses one can safely assume that the NPP
                            is well behind the front lens.

                            --
                            Erik Krause
                            http://www.erik-krause.de
                          • Uri
                            As Scott and others said, for shooting with a telephoto lens, if the objects are relatively far from the camera, the NPP does not matter. Here s a link to a
                            Message 13 of 14 , Sep 7, 2010
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                              As Scott and others said, for shooting with a telephoto lens, if the objects are relatively far from the camera, the NPP does not matter.

                              Here's a link to a gigabit partial pano, made with 4x39 (156) shots with a 300mm lens on a Nikon D700. Regular tripod head. No trouble at all with stitching in PTGui.

                              http://www.uricogan.com/osoyoos/
                            • Mark D. Fink
                              ... Great - thanks Erik! Mark www.pinnacle-vr.com www.northernlight.net www.virtual-travels.com
                              Message 14 of 14 , Sep 7, 2010
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                                > -----Original Message-----
                                > From: PanoToolsNG@yahoogroups.com [mailto:PanoToolsNG@yahoogroups.com] On
                                > Behalf Of Erik Krause
                                > Sent: Tuesday, September 07, 2010 4:24 PM
                                > To: PanoToolsNG@yahoogroups.com
                                > Subject: [PanoToolsNG] Re: NP 16mm and 70-200mm
                                >
                                > Am 07.09.2010 13:57, schrieb Mark D. Fink:
                                > > Is it generally true that the NPP on telephoto lenses is well behind the
                                > > front element, in some cases, (such as the Nikkor AF-S VR 300 mm), well
                                > > behind the film plane? Are there any exceptions to this that anyone is
                                > aware
                                > > of?
                                >
                                > Since a telephoto lens by definition is shorter than it's own focal
                                > length it should be generally true. However, no one stops you putting
                                > the limiting aperture in front of the front lens in which case the NPP
                                > would be there.
                                >
                                > But for unmodified telephoto lenses one can safely assume that the NPP
                                > is well behind the front lens.
                                >
                                > --
                                > Erik Krause
                                > http://www.erik-krause.de
                                Great - thanks Erik!

                                Mark
                                www.pinnacle-vr.com
                                www.northernlight.net
                                www.virtual-travels.com
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