No-parallax point - Revision history

MonochromeJim: Added this additional reference which I found via Wikipedia

2012-03-13T03:14:08Z

Added this additional reference which I found via Wikipedia

Beeswax: /* Methods for finding the NPP location(s) of a specific lens */

2011-02-16T01:26:25Z

‎Methods for finding the NPP location(s) of a specific lens

Beeswax: /* Methods for finding the NPP location(s) of a specific lens */

2011-02-16T01:24:56Z

‎Methods for finding the NPP location(s) of a specific lens

Beeswax: /* Methods for finding the NPP location(s) of a specific lens */ add link

2011-02-08T21:48:14Z

‎Methods for finding the NPP location(s) of a specific lens: add link

Beeswax: /* In theory */ added useful link

2011-02-08T21:29:10Z

‎In theory: added useful link

Beeswax: /* References */ updated link

2011-02-02T23:26:58Z

‎References: updated link

Erik Krause: /* See also */

2011-01-30T20:16:20Z

‎See also

Beeswax: /* Links */ slight re-organsation and added a couple of good links

2011-01-30T18:10:35Z

‎Links: slight re-organsation and added a couple of good links

Dezen: non existing link "focal length" changed to "Focal Length"

2009-12-06T16:42:33Z

non existing link "focal length" changed to "Focal Length"

Erik Krause: shortened

2007-11-17T22:55:24Z

shortened

@@ Line 28: / Line 28: @@
 *Rik Littlefield, [http://www.janrik.net/PanoPostings/NoParallaxPoint/TheoryOfTheNoParallaxPoint.pdf Theory of the "No-Parallax" Point in Panorama Photography]
 *John Bercovitz 1998, [http://www.angelfire.com/ca2/tech3d/images/persp.pdf Image-side Perspective and Stereoscopy] (SPIE proceedings vol. 3295). See section "3. Image-side perspective point" in particular for formulae relating entrance pupils, focal lengths and gaussian nodal points.
+*R. Barry Johnson 2008, [http://imaging.creol.ucf.edu/OSE5203/04%20Additional%20Material/3.0%20Optical%20Center%20of%20a%20Lens%20System.pdf Correctly making panoramic imagery and the meaning of optical center] SPIE Proc. 7060: 70600F.1–70600F.8. ISSN [http://www.worldcat.org/title/proceedings-of-spie-the-international-society-for-optical-engineering/oclc/298780637 0277-786X.] OCLC [http://www.worldcat.org/title/correctly-making-panoramic-imagery-and-the-meaning-of-optical-center-7060-42/oclc/278726950 278726950]
 ====Locating the NPP(s) of a specific lens ====
 *John Houghton, [http://www.johnhpanos.com/epcalib.htm Finding the No-Parallax Point].

@@ Line 29: / Line 29: @@
 *John Bercovitz 1998, [http://www.angelfire.com/ca2/tech3d/images/persp.pdf Image-side Perspective and Stereoscopy] (SPIE proceedings vol. 3295). See section "3. Image-side perspective point" in particular for formulae relating entrance pupils, focal lengths and gaussian nodal points.
-====Methods for finding the NPP location(s) of a specific lens ====
+====Locating the NPP(s) of a specific lens ====
 *John Houghton, [http://www.johnhpanos.com/epcalib.htm Finding the No-Parallax Point].
 *Big Ben's Panorama Tutorials, [http://www.path.unimelb.edu.au/~bernardk/tutorials/360/photo/nodal.html Determining the Nodal Point of a Lens].

@@ Line 33: / Line 33: @@
 *Big Ben's Panorama Tutorials, [http://www.path.unimelb.edu.au/~bernardk/tutorials/360/photo/nodal.html Determining the Nodal Point of a Lens].
 *Kaidan, [http://www.kaidan.com/nodalpoint.html How to Find Your Camera's Nodal Point].
-*Alain Hamblenne, [http://www.outline.be/quicktime/tuto/ The Grid]
+*Alain Hamblenne, [http://www.outline.be/quicktime/tuto/ The Grid].
 *[http://michel.thoby.free.fr/ Michel Thoby], especially [http://michel.thoby.free.fr/SIGMA8mm/Alpha%20test%20300D/Nodal%20point%20of%20SIGMA%208mm.html Nodal point location for the SIGMA 8mm f:4 lens], which describes an interesting approach using a laser pointer.
 *"Use an SLR as a rangefinder ..." See section "5. Miscellanea" of John Bercovitz 1998, [http://www.angelfire.com/ca2/tech3d/images/persp.pdf Image-side Perspective and Stereoscopy] (SPIE proceedings vol. 3295).
 [[Category:Glossary]]

@@ Line 30: / Line 30: @@
 ====Methods for finding the NPP location(s) of a specific lens ====
 *Big Ben's Panorama Tutorials, [http://www.path.unimelb.edu.au/~bernardk/tutorials/360/photo/nodal.html Determining the Nodal Point of a Lens].
 *Kaidan, [http://www.kaidan.com/nodalpoint.html How to Find Your Camera's Nodal Point].
 *Alain Hamblenne, [http://www.outline.be/quicktime/tuto/ The Grid]
 *[http://michel.thoby.free.fr/ Michel Thoby], especially [http://michel.thoby.free.fr/SIGMA8mm/Alpha%20test%20300D/Nodal%20point%20of%20SIGMA%208mm.html Nodal point location for the SIGMA 8mm f:4 lens], which describes an interesting approach using a laser pointer.
-*"Use an SLR as a rangefinder ..." See section "5. Miscellanea" of John Bercovitz 1998, [http://www.angelfire.com/ca2/tech3d/images/persp.pdf Image-side Perspective and Stereoscopy] (SPIE proceedings vol. 3295) .
+*"Use an SLR as a rangefinder ..." See section "5. Miscellanea" of John Bercovitz 1998, [http://www.angelfire.com/ca2/tech3d/images/persp.pdf Image-side Perspective and Stereoscopy] (SPIE proceedings vol. 3295).
 [[Category:Glossary]]

@@ Line 25: / Line 25: @@
 ====In theory====
 *Rik Littlefield, [http://www.janrik.net/PanoPostings/NoParallaxPoint/TheoryOfTheNoParallaxPoint.pdf Theory of the "No-Parallax" Point in Panorama Photography]
 *John Bercovitz 1998, [http://www.angelfire.com/ca2/tech3d/images/persp.pdf Image-side Perspective and Stereoscopy] (SPIE proceedings vol. 3295). See section "3. Image-side perspective point" in particular for formulae relating entrance pupils, focal lengths and gaussian nodal points.

@@ Line 19: / Line 19: @@
 ==References==
-#Kerr, Douglas A. "[http://doug.kerr.home.att.net/pumpkin/Pivot_Point.pdf The Proper Pivot Point for Panoramic Photography]" ''The Pumpkin'' (2005). Accessed [[2007-01-14]].
+#Kerr, Douglas A. "[http://dougkerr.net/Pumpkin/articles/Pivot_Point.pdf The Proper Pivot Point for Panoramic Photography]" ''The Pumpkin'' (2005). Accessed 2011-02-02.
-#van Walree, Paul "[http://www.vanwalree.com/optics/misconceptions.html#m6 Misconceptions in photographic optics]", Item #6. Accessed [[2007-01-14]].
+#van Walree, Paul "[http://www.vanwalree.com/optics/misconceptions.html#m6 Misconceptions in photographic optics]", Item #6. Accessed 2011-02-02.
 == Links ==

@@ Line 15: / Line 15: @@
 ==See also==
-*[[Nodal point adapters]]
+*[[NPP adapters]]
 *[[Entrance Pupil Database]]

@@ Line 4: / Line 4: @@
 With most lenses, there is one special point around which you can rotate your camera and get no parallax. This special "'''no-parallax point'''" is the center of the lens's '''entrance pupil''', a virtual aperture within the lens. In the panorama photography community, this special point is often called the "'''nodal point'''", but it is in fact unrelated to the actual nodal points of the lens.<sup>[[#References|1]],[[#References|2]]</sup> The actual nodal points are other points on the optical path, which are of no significance to most photographers. The no-parallax point is also the "center of perspective", but this term is not commonly used and does not describe why the no-parallax point is important.
-The entrance pupil is the image of the limiting aperture or diaphragm, as seen through the front of the lens. The image seen may be magnified by the effect of the lens elements in front of it, and the image is displaced from the actual position of the aperture. It is the center of this image about which the camera must be rotated to avoid parallax. Interestingly, the entrance pupil is important in another way: the [[f-number]] of a lens is actually the ratio of the [[focal length]] to the diameter of the entrance pupil, not to the diameter of the physical aperture inside the camera.
+The entrance pupil is the image of the limiting aperture or diaphragm, as seen through the front of the lens. The image seen may be magnified by the effect of the lens elements in front of it, and the image is displaced from the actual position of the aperture. It is the center of this image about which the camera must be rotated to avoid parallax. Interestingly, the entrance pupil is important in another way: the [[f-number]] of a lens is actually the ratio of the [[Focal Length |focal length ]] to the diameter of the entrance pupil, not to the diameter of the physical aperture inside the camera.
 Everything considered, the best term for the no-parallax point may be (surprise!) the "no-parallax point".  "Entrance pupil" is correct although a bit imprecise to a geometry purist; it makes a good term for searching the literature and would be preferred in formal writing.  "Nodal point" is commonly-used, but incorrect and leads to confusion.  It should be avoided when writing and interpreted with caution in reading the literature.

← Older revision		Revision as of 22:55, 17 November 2007
Line 1:		Line 1:
−	{{Glossary\|The special point that you have to rotate your camera around, to avoid parallax errors. Commonly referred to as the [[Nodal Point]] ~~or better [[no-parallax point]], which see for more information~~.}}	+	{{Glossary\|The special point that you have to rotate your camera around, to avoid parallax errors. Commonly (and falsely) referred to as the [[Nodal Point]].}}
	If you rotate your camera around some randomly chosen point, your images may show [[parallax]] and be difficult to stitch.		If you rotate your camera around some randomly chosen point, your images may show [[parallax]] and be difficult to stitch.