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How to create a high resolution image of a hammer

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  • johntunley
    Hi everyone, I want to create a series of high resolution (about 24,000 x 12,000 pixels) images for large prints (about 2m x 1m) of hand tools, initially a
    Message 1 of 15 , Jan 20, 2013
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      Hi everyone,

      I want to create a series of high resolution (about 24,000 x 12,000 pixels) images for large prints (about 2m x 1m) of hand tools, initially a hammer. The hammer is laid flat on a white background and I am using a Sony NEX7 supported on an RRS pano head and a Gitzo tripod. Importing the resulting TIFFs from Photoshop into PTGui gives me an well stitched rectilinear image.

      My problem is with depth of field. Using a Minolta 100mm Macro lens on an adaptor, the camera sensor is about 1.1m above the hammer. There is not enough depth of field at f8 to give sharp detail over the extremities of the handle and hammer head. The lens is also covering too wide a field of view such that I am only stitching from 4 images and achieving about half the desired resolution. If I were to use a lens of longer focal length to reduce the angle of view, and then take more images to increase the resolution, the depth of field would also reduce further.

      I can reduce the aperture further, perhaps down to f22, but this will lead to loss of sharpness due to diffraction. Maybe I need to consider a longer lens and focus stacking? Any other ideas? This is self-funded and I'm not looking to buy a very high resolution camera!

      Thanks in anticipation,

      John T
    • Erik Krause
      ... What you need is focus stacking. There are several solutions to stack images taken at different focus settings such that only the sharpest parts are
      Message 2 of 15 , Jan 20, 2013
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        Am 20.01.2013 19:04, schrieb johntunley:

        > There is not enough depth of field at f8 to give sharp detail over
        > the extremities of the handle and hammer head.

        What you need is focus stacking. There are several solutions to stack
        images taken at different focus settings such that only the sharpest
        parts are combined. See http://en.wikipedia.org/wiki/Focus_stacking

        > The lens is also
        > covering too wide a field of view such that I am only stitching from
        > 4 images and achieving about half the desired resolution. If I were
        > to use a lens of longer focal length to reduce the angle of view, and
        > then take more images to increase the resolution, the depth of field
        > would also reduce further.

        True. But you don't need a larger focal length, since the macro lens
        should be able to go up to 1:1 scale. However, depth of field problem
        increases anyway since in macro regions DoF depends largely on the
        magnification scale and less on focal length.

        If you do focus stacking, use a macro slide, not the focus ring of the
        lens. This way the background magnification stays the same, which
        simplifies the stacking process.

        Good luck!

        --
        Erik Krause
        http://www.erik-krause.de
      • giant_klobasa_monster
        You might want to read about what Dani did - same as what you re trying but with faces :) He got himself a $15,000 robot to move the camera around. He also
        Message 3 of 15 , Jan 21, 2013
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          You might want to read about what Dani did - same as what you're trying but with faces :)

          He got himself a $15,000 robot to move the camera around.

          He also built himself a telecentric lens.


          http://www.kolor.com/forum/t11720-creating-an-xml-file-for-import-with-autopano

          --- In PanoToolsNG@yahoogroups.com, "johntunley" wrote:
          >
          > Hi everyone,
          >
          > I want to create a series of high resolution (about 24,000 x 12,000 pixels) images for large prints (about 2m x 1m) of hand tools, initially a hammer. The hammer is laid flat on a white background and I am using a Sony NEX7 supported on an RRS pano head and a Gitzo tripod. Importing the resulting TIFFs from Photoshop into PTGui gives me an well stitched rectilinear image.
          >
          > My problem is with depth of field. Using a Minolta 100mm Macro lens on an adaptor, the camera sensor is about 1.1m above the hammer. There is not enough depth of field at f8 to give sharp detail over the extremities of the handle and hammer head. The lens is also covering too wide a field of view such that I am only stitching from 4 images and achieving about half the desired resolution. If I were to use a lens of longer focal length to reduce the angle of view, and then take more images to increase the resolution, the depth of field would also reduce further.
          >
          > I can reduce the aperture further, perhaps down to f22, but this will lead to loss of sharpness due to diffraction. Maybe I need to consider a longer lens and focus stacking? Any other ideas? This is self-funded and I'm not looking to buy a very high resolution camera!
          >
          > Thanks in anticipation,
          >
          > John T
          >
        • Adrien Fontvielle
          This guy did the same for a lighter budget and with spare parts of an old scanner. Not the same percision but should do the trick :
          Message 4 of 15 , Jan 21, 2013
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            This guy did the same for a lighter budget and with spare parts of an old scanner. Not the same percision but should do the trick :
            http://hackaday.com/2013/01/20/flatbed-scanner-eliminates-the-perils-of-macro-photography/


            Adrien Fontvielle


            2013/1/21 giant_klobasa_monster <panoramas@...>
             



            You might want to read about what Dani did - same as what you're trying but with faces :)

            He got himself a $15,000 robot to move the camera around.

            He also built himself a telecentric lens.

            http://www.kolor.com/forum/t11720-creating-an-xml-file-for-import-with-autopano



            --- In PanoToolsNG@yahoogroups.com, "johntunley" wrote:
            >
            > Hi everyone,
            >
            > I want to create a series of high resolution (about 24,000 x 12,000 pixels) images for large prints (about 2m x 1m) of hand tools, initially a hammer. The hammer is laid flat on a white background and I am using a Sony NEX7 supported on an RRS pano head and a Gitzo tripod. Importing the resulting TIFFs from Photoshop into PTGui gives me an well stitched rectilinear image.
            >
            > My problem is with depth of field. Using a Minolta 100mm Macro lens on an adaptor, the camera sensor is about 1.1m above the hammer. There is not enough depth of field at f8 to give sharp detail over the extremities of the handle and hammer head. The lens is also covering too wide a field of view such that I am only stitching from 4 images and achieving about half the desired resolution. If I were to use a lens of longer focal length to reduce the angle of view, and then take more images to increase the resolution, the depth of field would also reduce further.
            >
            > I can reduce the aperture further, perhaps down to f22, but this will lead to loss of sharpness due to diffraction. Maybe I need to consider a longer lens and focus stacking? Any other ideas? This is self-funded and I'm not looking to buy a very high resolution camera!
            >
            > Thanks in anticipation,
            >
            > John T
            >


          • paul womack
            ... You will want to select your camera-object distance to control perspective effects - extreme close ups (allowed by wide angle lenses) can look very odd.
            Message 5 of 15 , Jan 22, 2013
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              johntunley wrote:
              > Hi everyone,
              >
              > I want to create a series of high resolution (about 24,000 x 12,000 pixels) images for large prints (about 2m x 1m) of hand tools, initially a hammer. The hammer is laid flat on a white background and I am using a Sony NEX7 supported on an RRS pano head and a Gitzo tripod. Importing the resulting TIFFs from Photoshop into PTGui gives me an well stitched rectilinear image.
              >
              > My problem is with depth of field. Using a Minolta 100mm Macro lens on an adaptor, the camera sensor is about 1.1m above the hammer. There is not enough depth of field at f8 to give sharp detail over the extremities of the handle and hammer head. The lens is also covering too wide a field of view such that I am only stitching from 4 images and achieving about half the desired resolution. If I were to use a lens of longer focal length to reduce the angle of view, and then take more images to increase the resolution, the depth of field would also reduce further.
              >
              > I can reduce the aperture further, perhaps down to f22, but this will lead to loss of sharpness due to diffraction. Maybe I need to consider a longer lens and focus stacking? Any other ideas? This is self-funded and I'm not looking to buy a very high resolution camera!

              You will want to select your camera-object distance to control
              perspective effects - extreme close ups (allowed
              by wide angle lenses) can look very odd.

              And - yes - you need focus stacking. But I'm not clear about the maths
              of combining focus stacking (using a macro-slide) and a pano head,
              since I suspect the movement of the slide will move the NP point.

              I have done a hi-res non-mosaic (in Hugin terms) scan/photograph of a map
              in this way (no focus stacking)

              (around 12000 x 8000 pixels)

              http://www.panotools.org/mailarchive/msg/61023

              http://www.panotools.org/mailarchive/msg/70805


              BugBear
            • johntunley
              Thanks very much for all your responses. I was a little reluctant to go in closer to the subject as suggested by Erik because of the odd perspective that may
              Message 6 of 15 , Jan 23, 2013
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                Thanks very much for all your responses. I was a little reluctant to go in closer to the subject as suggested by Erik because of the odd perspective that may result, as pointed out by Bugbear. However, before purchasing yet another lens, I decided to give it a try by reducing the sensor to subject distance to about 0.7m. My first attempt was a disaster, the images would not join, then I found that the tripod ball head had slippedÂ…

                My second attempt went very well with a near perfect stitch of 21 frames. The perspective effect was apparent (looking slightly at the underside of the hammer head, rather than square on), but I did not find it objectionable. I don't at present have a focus slider so decided to give lens focus adjustment a try and produced two more stitched images at different focus planes.

                There was some differences in magnification between the individual images, as mentioned by Erik. However this was compensated when I imported them into Photoshop (CS6) as a stack and aligned that stack, resulting in 3 equi-sized images in layers. I then blended the layer stack and was very happy with the stitched and focus blended image which resulted, only requiring a minor bit of tweaking. By good guess work, or more likely pure chance, the resultant image was virtually at my target size (12k x 24k) at 11,800 x 23,600 pixels.

                Thanks again for your support!

                John T

                --- In PanoToolsNG@yahoogroups.com, "johntunley" wrote:
                >
                > Hi everyone,
                >
                > I want to create a series of high resolution (about 24,000 x 12,000 pixels) images for large prints (about 2m x 1m) of hand tools, initially a hammer. The hammer is laid flat on a white background and I am using a Sony NEX7 supported on an RRS pano head and a Gitzo tripod. Importing the resulting TIFFs from Photoshop into PTGui gives me an well stitched rectilinear image.
                >
                > My problem is with depth of field. Using a Minolta 100mm Macro lens on an adaptor, the camera sensor is about 1.1m above the hammer. There is not enough depth of field at f8 to give sharp detail over the extremities of the handle and hammer head. The lens is also covering too wide a field of view such that I am only stitching from 4 images and achieving about half the desired resolution. If I were to use a lens of longer focal length to reduce the angle of view, and then take more images to increase the resolution, the depth of field would also reduce further.
                >
                > I can reduce the aperture further, perhaps down to f22, but this will lead to loss of sharpness due to diffraction. Maybe I need to consider a longer lens and focus stacking? Any other ideas? This is self-funded and I'm not looking to buy a very high resolution camera!
                >
                > Thanks in anticipation,
                >
                > John T
                >
              • Erik Krause
                ... Inspired by your question I searched a bit and found Zerene Stacker, a program made by a (former) member of this group, Rik Littlefield. There is a lot of
                Message 7 of 15 , Jan 23, 2013
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                  Am 23.01.2013 11:44, schrieb johntunley:
                  > I don't at present have a focus slider so decided to give lens focus
                  > adjustment a try and produced two more stitched images at different
                  > focus planes..

                  Inspired by your question I searched a bit and found Zerene Stacker, a
                  program made by a (former) member of this group, Rik Littlefield. There
                  is a lot of information at http://zerenesystems.com/ and interestingly
                  he favors the focus ring method.

                  He is also administrator at http://www.photomacrography.net/forum/ where
                  you can find a real wealth of information, including how to create and
                  use a telecentric lens system, which allows for perspective-less focus
                  stacking and stitching.

                  --
                  Erik Krause
                  http://www.erik-krause.de
                • giant_klobasa_monster
                  Unless I misunderstand, if you use a telecentric lens, you can more effectively stitch images by shifting the camera left-right and up-down, rather than
                  Message 8 of 15 , Jan 23, 2013
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                    Unless I misunderstand, if you use a telecentric lens, you can more effectively stitch images by shifting the camera left-right and up-down, rather than rotating it around a point.

                    Maybe you could mount a camera (with telecentric lens) on a kind of 2d plotter assembly, and shoot an object by pretending the camera sensor is a scanner?

                    Or am I mistaken? :)


                    --- In PanoToolsNG@yahoogroups.com, paul womack wrote:
                    >
                    > johntunley wrote:
                    > > Hi everyone,
                    > >
                    > > I want to create a series of high resolution (about 24,000 x 12,000 pixels) images for large prints (about 2m x 1m) of hand tools, initially a hammer. The hammer is laid flat on a white background and I am using a Sony NEX7 supported on an RRS pano head and a Gitzo tripod. Importing the resulting TIFFs from Photoshop into PTGui gives me an well stitched rectilinear image.
                    > >
                    > > My problem is with depth of field. Using a Minolta 100mm Macro lens on an adaptor, the camera sensor is about 1.1m above the hammer. There is not enough depth of field at f8 to give sharp detail over the extremities of the handle and hammer head. The lens is also covering too wide a field of view such that I am only stitching from 4 images and achieving about half the desired resolution. If I were to use a lens of longer focal length to reduce the angle of view, and then take more images to increase the resolution, the depth of field would also reduce further.
                    > >
                    > > I can reduce the aperture further, perhaps down to f22, but this will lead to loss of sharpness due to diffraction. Maybe I need to consider a longer lens and focus stacking? Any other ideas? This is self-funded and I'm not looking to buy a very high resolution camera!
                    >
                    > You will want to select your camera-object distance to control
                    > perspective effects - extreme close ups (allowed
                    > by wide angle lenses) can look very odd.
                    >
                    > And - yes - you need focus stacking. But I'm not clear about the maths
                    > of combining focus stacking (using a macro-slide) and a pano head,
                    > since I suspect the movement of the slide will move the NP point.
                    >
                    > I have done a hi-res non-mosaic (in Hugin terms) scan/photograph of a map
                    > in this way (no focus stacking)
                    >
                    > (around 12000 x 8000 pixels)
                    >
                    > http://www.panotools.org/mailarchive/msg/61023
                    >
                    > http://www.panotools.org/mailarchive/msg/70805
                    >
                    >
                    > BugBear
                    >
                  • johntunley
                    Thanks Erik, I looked at Zerene Stacker too but I found that Photoshop did a good job, at least in this instance, so I stayed with the software I had
                    Message 9 of 15 , Jan 25, 2013
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                      Thanks Erik,

                      I looked at Zerene Stacker too but I found that Photoshop did a good job, at least in this instance, so I stayed with the software I had available. If time permits, I'll compare the Photoshop results with Zerene and Helicon.

                      The final images will be shown in the UK at Format:

                      http://formatfestival.com

                      Thanks for the link to the telecentric lens articles which are worth a more detailed look, unfortunately timescales prevent that just now.

                      Regards,

                      John T



                      --- In PanoToolsNG@yahoogroups.com, Erik Krause wrote:
                      >
                      > Am 23.01.2013 11:44, schrieb johntunley:
                      > > I don't at present have a focus slider so decided to give lens focus
                      > > adjustment a try and produced two more stitched images at different
                      > > focus planes..
                      >
                      > Inspired by your question I searched a bit and found Zerene Stacker, a
                      > program made by a (former) member of this group, Rik Littlefield. There
                      > is a lot of information at http://zerenesystems.com/ and interestingly
                      > he favors the focus ring method.
                      >
                      > He is also administrator at http://www.photomacrography.net/forum/ where
                      > you can find a real wealth of information, including how to create and
                      > use a telecentric lens system, which allows for perspective-less focus
                      > stacking and stitching.
                      >
                      > --
                      > Erik Krause
                      > http://www.erik-krause.de
                      >
                    • David
                      I ve used Zerene stacker for many stacked macro photos. Form all the reviews I ve been able to find it is one of the best. I also have an extra Melles Griot
                      Message 10 of 15 , Jan 25, 2013
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                        I've used Zerene stacker for many stacked macro photos. Form all the reviews I've been able to find it is one of the best.

                        I also have an extra Melles Griot telecentric lens if anyone is interested. Here is a pan and stitched sample (not stacked):
                        http://www.flickr.com/photos/dbur971/4732547090/in/set-72157627813468144

                        Here is what the lens looks like:
                        http://www.flickr.com/photos/dbur971/4732535550/in/photostream

                        Front of the lens is about 3" across, I use it with 55mm Nikkor macro lens as base lens. Seems to work with the Canon 50mm as well.

                        It may require more images than you want for your hammer, but doable.

                        David B


                        --- In PanoToolsNG@yahoogroups.com, Erik Krause wrote:
                        >
                        > Am 23.01.2013 11:44, schrieb johntunley:
                        > > I don't at present have a focus slider so decided to give lens focus
                        > > adjustment a try and produced two more stitched images at different
                        > > focus planes..
                        >
                        > Inspired by your question I searched a bit and found Zerene Stacker, a
                        > program made by a (former) member of this group, Rik Littlefield. There
                        > is a lot of information at http://zerenesystems.com/ and interestingly
                        > he favors the focus ring method.
                        >
                        > He is also administrator at http://www.photomacrography.net/forum/ where
                        > you can find a real wealth of information, including how to create and
                        > use a telecentric lens system, which allows for perspective-less focus
                        > stacking and stitching.
                        >
                        > --
                        > Erik Krause
                        > http://www.erik-krause.de
                        >
                      • Erik Krause
                        ... Just for the records: There are several combinations of standard lenses and standard achromatic close-up lenses that make up a (near) telecentric combo:
                        Message 11 of 15 , Jan 26, 2013
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                          Am 25.01.2013 11:43, schrieb johntunley:
                          > Thanks for the link to the telecentric lens articles which are worth
                          > a more detailed look, unfortunately timescales prevent that just
                          > now.

                          Just for the records: There are several combinations of standard lenses
                          and standard achromatic close-up lenses that make up a (near)
                          telecentric combo: f.e the Canon EF 100mm 1:2.8 IS USM macro lens
                          together with a 5dpt close-up lens as well as the EF 100-400 1:4.5-5.6
                          IS USM (at 400mm) with a 2dpt close-up lens. Both must be used at near
                          focus.

                          I've discovered both accidentally when playing around with close-up
                          lenses I happen to own. For the EF 100mm I used a step down ring
                          (67->58mm) which doesn't cause vignetting and allows to use my
                          collection of 58mm filters. It doesn't work with the older Canon 100mm
                          macro lenses though...

                          The 2dpt close-up lens is recycled from a 500mm f/8 Beroflex telephoto
                          lens (where the back lens group was blinded by bad lens fungus). I use
                          it with a step down ring (77->72mm). I mention this because the distance
                          between close-up lens and base lens is critical.

                          In fact any combination of close-up lens and base lens should work if
                          some kind of extension tube is used which places the focal point of the
                          close-up lens in the entrance pupil of the base lens, which effectively
                          projects the entrance pupil and hence the no-parallax-point at infinity
                          behind the camera.

                          --
                          Erik Krause
                          http://www.erik-krause.de
                        • Gerhard Killesreiter
                          ... Hash: SHA1 ... Is there a tutorial how I can determine which add-on lens I need to buy for a given macro lens? I have a Sigma 105mm macro. Cheers, Gerhard
                          Message 12 of 15 , Jan 26, 2013
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                            Hash: SHA1


                            > In fact any combination of close-up lens and base lens should work
                            > if some kind of extension tube is used which places the focal point
                            > of the close-up lens in the entrance pupil of the base lens, which
                            > effectively projects the entrance pupil and hence the
                            > no-parallax-point at infinity behind the camera.


                            Is there a tutorial how I can determine which add-on lens I need to
                            buy for a given macro lens?

                            I have a Sigma 105mm macro.

                            Cheers,
                            Gerhard


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                            =LlRe
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                          • Erik Krause
                            ... I don t know of any. However, it s not limited to macro lenses, any lens will do as a base lens. First determine where the no-parallax-point (NPP) of the
                            Message 13 of 15 , Jan 26, 2013
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                              Am 26.01.2013 15:59, schrieb Gerhard Killesreiter:
                              >> >In fact any combination of close-up lens and base lens should work
                              >> >if some kind of extension tube is used which places the focal point
                              >> >of the close-up lens in the entrance pupil of the base lens, which
                              >> >effectively projects the entrance pupil and hence the
                              >> >no-parallax-point at infinity behind the camera.
                              >
                              > Is there a tutorial how I can determine which add-on lens I need to
                              > buy for a given macro lens?

                              I don't know of any. However, it's not limited to macro lenses, any lens
                              will do as a base lens. First determine where the no-parallax-point
                              (NPP) of the base lens is just as for panorama shooting. Next calculate
                              the focal length of the close-up lens, it's 1/dpt in meters. So if it
                              has 2 dpt (diopters) the focal length is 50cm. Place the close-up lens
                              by it's focal length in front of the NPP of the base lens. In our
                              example you should place it 50cm in front of the NPP.
                              You can even use an inverted other lens if you don't have a close-up
                              lens, like Rik did in his setup:
                              http://www.photomacrography.net/forum/viewtopic.php?t=1032
                              In this case the correct position must be found by try and error

                              Another combo can be found here:
                              http://www.photomacrography.net/forum/viewtopic.php?t=18323

                              For more one telecentric macro shooting search Rik's page for
                              "telecentr": http://janrik.net/RiksLinks.html

                              --
                              Erik Krause
                              http://www.erik-krause.de
                            • Lionel
                              Companies like JD Edwards, Melles Griot and other have some tutorials that explain exactly what telecentricity is. Based on my research on this topic, your
                              Message 14 of 15 , Jan 26, 2013
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                                Companies like JD Edwards, Melles Griot and other have some tutorials that explain exactly what "telecentricity" is. Based on my research on this topic, your best resource will be the links to photomacrography.net that were posted earlier. As far as I can tell, this is relatively novel ground for photographers in general; Rik Littlefield's articles are the best I've found.

                                Regards
                                --- In PanoToolsNG@yahoogroups.com, Gerhard Killesreiter wrote:
                                >
                                > -----BEGIN PGP SIGNED MESSAGE-----
                                > Hash: SHA1
                                >
                                >
                                > > In fact any combination of close-up lens and base lens should work
                                > > if some kind of extension tube is used which places the focal point
                                > > of the close-up lens in the entrance pupil of the base lens, which
                                > > effectively projects the entrance pupil and hence the
                                > > no-parallax-point at infinity behind the camera.
                                >
                                >
                                > Is there a tutorial how I can determine which add-on lens I need to
                                > buy for a given macro lens?
                                >
                                > I have a Sigma 105mm macro.
                                >
                                > Cheers,
                                > Gerhard
                                >
                                >
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                                > Version: GnuPG v1.4.11 (GNU/Linux)
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                                > iEYEARECAAYFAlED71AACgkQfg6TFvELooRDnwCglMgd/q3DvALvmapmUsYqVwI8
                                > dckAoLwQJo3t5TnCjui8Tu38/rvYlPaH
                                > =LlRe
                                > -----END PGP SIGNATURE-----
                                >
                              • Rick Drew
                                I ve also used my desktop scanner. My old model would do legal size scans up to 4800 dpi. I d scan old coins at some phenomenal resolution. From:
                                Message 15 of 15 , Jan 26, 2013
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                                  I’ve also used my desktop scanner. My old model would do legal size scans up to 4800 dpi. I’d scan old coins at some phenomenal resolution.

                                   

                                  From: PanoToolsNG@yahoogroups.com [mailto:PanoToolsNG@yahoogroups.com] On Behalf Of Lionel
                                  Sent: 2013-01-26 3:52 PM
                                  To: PanoToolsNG@yahoogroups.com
                                  Subject: [PanoToolsNG] Re: How to create a high resolution image of a hammer

                                   

                                   


                                  Companies like JD Edwards, Melles Griot and other have some tutorials that explain exactly what "telecentricity" is. Based on my research on this topic, your best resource will be the links to photomacrography.net that were posted earlier. As far as I can tell, this is relatively novel ground for photographers in general; Rik Littlefield's articles are the best I've found.

                                  Regards

                                  --- In PanoToolsNG@yahoogroups.com, Gerhard Killesreiter wrote:
                                  >
                                  > -----BEGIN PGP SIGNED MESSAGE-----
                                  > Hash: SHA1
                                  >
                                  >
                                  > > In fact any combination of close-up lens and base lens should work
                                  > > if some kind of extension tube is used which places the focal point
                                  > > of the close-up lens in the entrance pupil of the base lens, which
                                  > > effectively projects the entrance pupil and hence the
                                  > > no-parallax-point at infinity behind the camera.
                                  >
                                  >
                                  > Is there a tutorial how I can determine which add-on lens I need to
                                  > buy for a given macro lens?
                                  >
                                  > I have a Sigma 105mm macro.
                                  >
                                  > Cheers,
                                  > Gerhard
                                  >
                                  >
                                  > -----BEGIN PGP SIGNATURE-----
                                  > Version: GnuPG v1.4.11 (GNU/Linux)
                                  >
                                  > iEYEARECAAYFAlED71AACgkQfg6TFvELooRDnwCglMgd/q3DvALvmapmUsYqVwI8
                                  > dckAoLwQJo3t5TnCjui8Tu38/rvYlPaH
                                  > =LlRe
                                  > -----END PGP SIGNATURE-----
                                  >

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