Stereographic projection

16.4: Stereographic projection - Mathematics LibreText

16.4: Stereographic projection. Consider the unit sphere Σ centered at the origin ( 0, 0, 0). This sphere can be described by the equation x 2 + y 2 + z 2 = 1. Suppose that Π denotes the x y -plane; it is defined by the equation z = 0. Clearly, Π runs thru the center of Σ Stereographic Projection. A map projection obtained by projecting points on the surface of sphere from the sphere's north pole to point in a plane tangent to the south pole (Coxeter 1969, p. 93). In such a projection, great circles are mapped to circles , and loxodromes become logarithmic spirals . Stereographic projections have a very simple. The stereographic projection is a one-to-one mapping of the extended plane C ¯ onto the sphere S. The sphere S is called the Riemann sphere . The stereographical projection has the property that the angles between two (differentiable) curves in C and the angle between their images on S are equal The stereographic projection is a projection of points from the surface of a sphere on to its equatorial plane. The projection is defined as shown in Fig. 1. If any point P on the surface of the sphere is joined to the south pole S and the line PS cuts the equatorial plane at p, then p is the stereographic projection of P

Stereographic Projection -- from Wolfram MathWorl

Stereographic Projection - an overview ScienceDirect Topic

Stereographic projection in crystallography is a helpful and illustrative tool when investigating atomic planes or directions and visualizing various orientation dependent phenomena. In stereographic projection crystal directions are projected onto a plane Stereographic projection is about representing planar and linear features in a two-dimensional diagram. The orientation of a plane is represented by imagining the plane to pass through the centre of a sphere (Fig. 1a). The line of intersection between the plane and the sphere will then represent a circle, and this circle is formally known as a great circle. Except for the field of crystallography, where upper-hemisphere projection is used, geologists use the lower part of the.

(IUCr) The stereographic projectio

Stereographic Projection , 2D Map Mapping on 3D i.e Plane maps on sphere . About Press Copyright Contact us Creators Advertise Developers Terms Privacy Policy & Safety How YouTube works Test new. stereographic projection in order to use it in morphological crystallography of polycrystalline materials. The stereographic projection is a projection of points from the surface of a sphere on to its equatorial plane and it provides a useful way to conveying information about the orientation of lines and planes in 3-dimensional (3D) space. Stereographic projection can be defined as a.

This shows a 3d print of a mathematical sculpture I produced using shapeways.com. This model is available at http://shpws.me/q41V One particular kind of projection used for representing spheres and circles on spheres in two dimensions (ie on the climates of an astrolabe, or on some maps of the earth or celestial sphere) is stereographic projection. Stere(o) hails from the Greek stereos for solid, while graphic comes from the Greek graphicus meaning formed by writing, drawing, or engraving. Also, a projection is defined by Webster's Dictionary as a systematic presentation of intersecting coordinate lines on a. ステレオ投影(ステレオとうえい、英: stereographic projection )は、球面を平面に投影する方法の一つである。ステレオ投影は複素解析学、地図学、結晶学、写真術など様々な分野で重要である。 stereographic projection の訳語は分野によって異なる Stereographic projection is conformal, meaning that it preserves angles between curves. To see this, take a point p ∈ S2 \ {n}, let Tp denote the tangent plane to S2 at p, and let Tn denote the tangent plane to S2 at n. Working first in the 0np-plane (see figure 2), we have equal angles α and right angles between the radii and the tangent planes, hence equal angles β, hence equal angles. Stereographic projection is the name for a specific homeomorphism (for any n ∈ ℕ n \in \mathbb{N}) form the n-sphere S n S^n with one point p ∈ S n p \in S^n removed to the Euclidean space ℝ n \mathbb{R}^

Stereographic Projection • Stereographic projection is one of the convenient methods of projecting the linear and planar features. • This method is used extensively for the determination of angular relationship among the lines as well as planes. • In geotechnical engineering, it provides a quick and reliable picture of the discontinuities and their intersections. • It is also used for. t. e. In geometry, the stereographic projection is a particular mapping ( function) that projects a sphere onto a plane. The projection is defined on the entire sphere, except at one point: the projection point. Where it is defined, the mapping is smooth and bijective

Stereographic projection is one way of making maps, and it adopts the second strategy. It has been used since ancient times for this purpose, and at least one of its basic geometrical properties was known even then. What is stereographic projection Stereographic Projection In this grasshopper example file you can create a stereographic projection by using 4 different approaches.Using an Image, UV mapping ,Mesh based and Curve based. Script by:Erfan Rezae Stereographic Projection. Stereographic projection is a method used in crystallography and structural geology to depict the angular relationships between crystal faces and geologic structures, respectively. Here we discuss the method used in crystallography, but it is similar to the method used in structural geology. Imagine again that we have a crystal inside of a sphere. This time, however. Procedure for plotting the stereographic projection of an inclined plane with a strike of 100, a dip of 40, and the pole to the plane. Tracing paper shown grey. Example problem: Construct the great circle representing the plane 120/50, and its pole. On the projection label the angles corresponding to the plane's strike, dip and numerical dip direction. Plotting a line in a plane by rake or. English: Stereographic projection of rational real points onto the unit circle, with size adjusted to reflect the relative change in the measure. Made with Mathematica and processed in Inkscape. Datum: 14. August 2008: Quelle: Eigenes Werk: Urheber: Silly rabbit: Lizenz. Ich, der Urheberrechtsinhaber dieses Werkes, veröffentliche es hiermit unter der folgenden Lizenz: Diese Datei ist unter.

Stereographic Projection Stereographic Projection in the Plane Consider the unit circle S1 defined by x2 + z2 = 1 in the (x,z)-plane. The point N = (0,1) is the north pole and its antipode S = (0,−1) is the south pole. Each non-horizontal line through N intersects the circle in exactly one point (x,z) 6= N Example: Stereographic and cylindrical map projections. Examples inspired by the thread at comp.text.tex about how to convert some hand drawn pictures into programmatic 3D sketches. The sketches present stereographic and cylindrical map projections and they pose some interesting challenges for doing them with a 2D drawing package PGF/TikZ THE STEREOGRAPHIC PROJECTION, A HANDY TOOL FOR THE PRACTICAL GEOLOGIST WALTER H. BUCHER Columbia University, New York City INTRODUCTION One of the chief skills which the work-er in structural geology must develop is facility in three-dimensional thinking and in ready visualization and computation of the angular relations between lines and planes in space. No other single, simple tool is so.

Stereographic projection has an additional compression parameter. At maximum compression the result is a true stereographic projection; reducing the compression moves the viewpoint from the pole into the center of the sphere, effectively morphing the view into a rectilinear projection. PTGui and PTGui Pro are products of New House Internet Services B.V., Rotterdam, The Netherlands. The PTGui. The stereographic projection has the property that all cir-cles on the sphere are mapped onto circles or straight lines on the plane, and therefore it is easy to map astronomical observations. We include a construction in Section3. and. Figure 2: Astrolabe watch. Up to the late 18th century the Mercator and stereographic projections were treated as completely unrelated. It was Johann Heinrich. This worksheets illustrates the stereographic projection from the unit sphere onto the plane. Using a slider, you can watch the sphere unfold into

Stereographic map projection - Wikipedi

Stereographic Projection Recently Published Documents. TOTAL DOCUMENTS. 299 (FIVE YEARS 59) H-INDEX. 14 (FIVE YEARS 4) Latest Documents Top Cited Related Keywords Top Authors Related Journals Latest Documents; Top Cited; Related Keywords; Top Authors; Related Journals; Determination of particular singular configurations of Stewart platform type of fixator by the stereographic projection metho Stereographic projection is conformal, meaning that it preserves angles between curves. To see this, take a point p ∈ S2 \ {n}, let Tp denote the tangent plane to S2 at p, and let Tn denote the tangent plane to S2 at n. Working first in the 0np-plane (see figure 2), we have equal angles α and right angles between the radii and the tangent planes, hence equal angles β, hence equal angles. Stereographic projection It is impossible to render paths on a sphere onto a flat surface in such a way that all distances remain the same. In drawing a map of a sphere, therefore, some compromises must be made. Most maps adopt one of two possible strategies: (1) areas are preserved, or (2) angles are preserved. Stereographic projection is one way of making maps, and it preserves angles. It.

projection math real lenses, matching this projection equidistant fisheye = e.g. Peleng 8mm f/3.5 Fisheye This is the ideal fisheye projection panotools uses internally stereographic = ⁡ e.g. Samyang 8 mm f/3.5 orthographi A stereographic projection is often used to visualize a self-rotatation function. As explained in the polarrfn documentation the self-rotatation function always has the symmetry (180-theta, 180+phi, kappa) regardless of the crystallographic symmetry (i.e. even if it's P1). This relates one hemisphere (theta = 0 to 90) to the other (theta = 180 to 90) so there's no point plotting both hemispheres Stereographic projects points on a spheroid directly to the plane. Learn about the Double Stereographic projection. All meridians and parallels are shown as circular arcs or straight lines. Graticular intersections are 90°. In the equatorial aspect, the parallels curve in opposite directions on either side of the equator. In the oblique case, only the parallel with the opposite sign to the. A stereographic projection is a projection of the sphere onto an infinite plane. It has a whole range of nice properties, that makes it ideal to present equirectangular panoramas: * it is conformal: all angles are conserved so (local) shapes are preserved. * it is azimuthal: the direction from the center of the projection is the true one

This exhibit illustrates stereographic projection using rays of light projecting through a model of the globe onto a large nearby wall. Visitors can rotate the globe around to put different parts of the world in the center of the projection, seeing how the distortion of the map changes. The globe is the most recognisable spherical design to project, but other patterned 3D printed spheres can. Stereographic projection maps the sphere (minus the north pole) to the plane. This is a one-to-one mapping that allows us to study the sphere by studying the plane instead. The idea is to point a light source at the north pole, and look at the shadows of points on the sphere as they appear on the plane below. In our movies below, the light is represented by a white sphere at the north pole. Braun Stereographic; Creator: Carl Braun (1867) Group: Cylindric : Property: Compromise : Other Names — Remarks — Jump to different depiction of this projection: Specified in [square brackets]: Actual size of the projection (minus the black or white background). When marked with [≈], sizes with and without background are approx. the same. Back to Overwiew . Braun Perspective Breusing. Stereographic projection is a powerful method, not just to solve relatively simple (but important) problems of dip and strike, but as an analytical tool for more complex structural geology. There are several good software programs and Apps to automate projections for large data sets. But before you dive into these digital tools, try the simple overlay first - there's nothing like a hands.

Stereographic Projection - University of Illinois Urbana

  1. Stereographic Projection. Geographers have devised all sorts of projections from the curved surface of a sphere in three-space to flat two-dimensional maps. We have already been studying one of the most useful mapping techniques, central projection from a viewing point to a horizontal plane. When the viewing point is at the top of a sphere that rests on the horizontal plane, central projection.
  2. Stereographic Projection. By Xah Lee. Date: 2006-08-30. Last updated: 2016-05-02. The following are images of stereographic projection. A grid on the floor projected onto a ball. sphere_proj_illus.nb. Suppose you have a beach ball sitting on a elaborately beautifully tiled floor. Now, suppose the top of the beach ball we call it North Pole
  3. WinWulff is a program for plotting stereographic projections of (hkl) and [uvw] vectors onto a Wulff-net. It is the successor to JWulff and the JWulff module in JCrystal . New (1.3.0): List and export 2-Theta values. New (1.3.0): Delete poles. New (1.3.0): Use a selected pole as rotation axis

stereographic projection - Deutsch-Übersetzung - Linguee

  1. Stereographic projection is one way to make a flat map of the earth. Because the earth is spherical, any map must distort shapes or sizes to some degree. Mathematically, a projection (or type of map) is described by a rule telling where (in the plane of the map paper) to draw the image of each point on the sphere. The rule for stereographic projection has a nice geometric description. Think of.
  2. dict.cc | Übersetzungen für 'stereographic projection' im Englisch-Deutsch-Wörterbuch, mit echten Sprachaufnahmen, Illustrationen, Beugungsformen,.
  3. Stereographic projection is a powerful method for solving geometric problems in structural geology. Unlike structure contouring and other map-based techniques, it preserves only the orientation of lines and planes with no ability to preserve position relationships. However, it is extremely useful, as orientation problems are very common in structural geology. Stereographic projection has been.
  4. Stereographic projection of the spherical panorama of the Last Supper sculpture by Michele Vedani in Esino Lario, Lombardy, Italy during Wikimania 2016 Vue circulaire des montagnes qu'on découvre du sommet du Glacier de Buet, Horace-Benedict de Saussure, Voyage dans les Alpes, précédés d'un essai sur l'histoire naturelle des environs de Geneve. Neuchatel, 1779-96, pl. 8. Some fisheye.
  5. The stereographic projection is a projection of points from the surface of a sphere on to its equatorial plane. The importance of the stereographic projection in crystallography derives from the fact that a set of points on the surface of the sphere provides a complete representation of a set of directions in three-dimensional space, the directions being the set of lines from the centre of the.
  6. Stereographic projection Given a point (u;v) 2R2, there is a unique line in R3 passing through (u;v;0) and (0;0;1). We de ne a map x: R2!R3 by letting x(u;v) be the intersection of this line with the unit sphere S2 ˆR3. That is, x(u;v) = 2u u2 + v2 + 1; 2v u2 + v2 + 1; u2 + v2 1 u2 + v2 + 1 : 1.Verify that the image of x is contained in S2. What is the image precisely? (Solution)We need to.

Stereographic Projection. Ask Question Asked 8 years, 4 months ago. Active 4 years, 2 months ago. Viewed 4k times 18 5 $\begingroup$ Say I want to represent points of the complex plane in the sphere $\Bbb S^2$ using stereographic projection. That is, the Riemann sphere: Specifically, it would be nice to be able to: Given the coordinates $(x,y)$ of a point of the plane, see the point and its. Stereographic projection is conformal, meaning that it preserves the angles at which curves cross each other (see figures). On the other hand, stereographic projection does not preserve area; in general, the area of a region of the sphere does not equal the area of its projection onto the plane This is successful on a platecarree projection, but when I try to switch to a south polar stereographic projection (using cartopy), my plot is wrong. The coastline of Antarctica does not match the data's outline of the continent. First, the part of the code that works: import numpy as np import numpy.ma as ma import xarray as xr from matplotlib import pyplot as plt filename = '/glade/scratch. Stereographic projection Throughout, we'll use the coordinate patch x: R2!R3 de ned by x(u;v) = 2u u2 + v2 + 1; 2v u2 + v2 + 1; u2 + v2 1 u2 + v2 + 1 : We won't repeat all of these solutions in section, but will focus on the last two problems. 1.Verify that the image of x is contained in S2. What is the image precisely Stereographic Projection Projection of 3D orientation data and symmetry of a crystal into 2D by preserving all the angular relationships First introduced by F.E Neuman and further developed by W.H Miller In mineralogy, it involves projection of faces, edges, mirror planes, and rotation axes onto a flat equatorial plane of a sphere, in correct angular relationships 5. Two Types of Stereonet.

Stereographic projection is used in geology to decipher the complexities of deformed rock by looking at the relationships between planes and linear structures; their bearings (trends) and angular relationships one with the other. The data is plotted on a stereonet as great circles and points (Wulff and Schmidt nets). A stereonet can become pretty messy where there is a lot of data - a. Stereographic projection establishes a correspondence not only between the points of the sphere and the plane, but also between points outside the sphere and circles on the plane. For a point outside the sphere, the polar plane intersects the sphere along a circle. Under stereographic projection, this circle is transformed to a circle on the plane, which is also considered as the stereographic. Gall Stereographic c Tobias Jung Mercator c Tobias Jung. 2. Comparison: Silhouette Map. Gall Stereographic. Click on projection's name to hide it. Grey areas: Superimposition of projections. Gall Stereographic Silhouette Map c Tobias Jung Mercator Silhouette Map c Tobias Jung. 3. Comparison: Tissot Indicatrix, 30° This is an orthographic projection of a stereographic projection. That is, 3d coordinate with an actual stereographic projection are used and projected on the screen via an orthographic projection. The dashed lines are achieved with an orgy of clips and reverse clips. One can vary the view parameters and coordinates of the point on the plane

From Wikipedia, The Free Encyclopedia. Share. Pi The stereographic projection was known to Hipparchus, Ptolemy and probably earlier to the Egyptians.It was originally known as the planisphere projection. Planisphaerium by Ptolemy is the oldest surviving document that describes it. One of its most important uses was the representation of celestial charts. The term planisphere is still used to refer to such charts

Miscellaneous Transformations and Projection

Stereographic projection. Author: Zbigniew Radziszewski. Stereographic projection preserves angles - the graphic proof -stereographic projection of the grid of a conventional globe oriented so that the N'-S' direction lies in the plane of projection -equator, all meridians-great circle-parallels except equator-small circle-azimuthalangle ϕ and pole distance ρ ('')NS N S⊥ Stereographic Projections W. B-Ott, Crystallography. Stereographic Projections B. D. Cullity, Elements of X-ray Diffraction-Only. Stereographic Projection to the Representation of Moving Targets in Air Traffic Control Systems Robert G. Mulholland '. DOT/FAA/CT-TN85/67 . Document is on file at the Technical Center . Library, Atlantic City Airport, N.J. 08405 . u.s. Deportmenf of . Tronsportoticn Federal AvIatIon AdminIsllation . Technical Center Atlantic City Airport, N.J. 08405, q '­ T. echniclli ~eport. Documentation. Stereographic projection for a cubic film with [100] normal. The book author ( Yougui Liao ) welcomes your comments, suggestions, and corrections, please click here for submission. If you let book author know once you have cited this book, the brief information of your publication will appear on the Times Cited page

Stereographic projection. Stereographic Projection h180° v180 ° Stereographic Projection is a conformal form of Fisheye Projection where the distance from the centre is not equivalent to the spatial angle. This is much easier on the eye for printing and display purposes. Stereographic is limited to a maximum horizontal (and vertical) angle of 360 degrees, images over 330 degrees are pretty. Re: stereographic projections. another approach is to look at problem as solids and booleans. I.e. assume point light source and a surrounding shell of a sphere which you want to cut into just as in the example links you sent. then do a boolean difference with the sphere shell. The result is the same

Stereographic Projection 3D-Printed Physical Model

Customizable stereographic picture projector v3 highres by threonin - Thingiverse of ~he properties of the spherical stereographic projection is rigorously retained while the others are only approximately fulfilled. The approach described in this report is one of a double projectiort. Ellipsoidal data is mapped conformally on a conformal sphere. Then, a second conformal mapping of the spherical data to the plane com- pletes the process. Since the two mappings are conformal. How to Modify an Image to Stereographic Projection: Have you ever seen those cool circular panorama that resembles the wide angle fish eye lenses but more spherical creating a little plane effect? Well, they are called stereographics. I stumbled upon this technique a few years ago and I find it real I want to project a netcdf file projected with the NSIDC Sea Ice Polar Stereographic North (EPSG:3411) to the WGS84 (EPSG:4326). The NETCDF data input file comes from Copernicus Marine Model.. I use gdalwarp on Windows (GDAL 3.0.2, released 2019/10/28) to perform this projection change Stereographic projection is a useful tool in geometry, but it also has been used for hundreds of years by mineralogists and cartographers alike. If it weren't for stereographic projection, our modern maps would not be nearly as effective or accurate as they are. This type of projection allows us to understand where certain countries are in relation to others, as well as providing the.

Video: 1.4: Stereographic Projection - Geosciences LibreText

Stereographic projection Facts for Kids

Lecture 10: Complex Analysis (Stereographic projection

I specialize in creating stereographic panorama's or (Little Planets) like the last image posted on this page and I am now wondering if it is possible to generate the stereographic projections (Little Planets) to an equirectangular panorama for building virtual tours. Part of the complication is that I have photoshopped the panorama's and they are now 1 flat image, not. Here you see how the stereographic projection of a sphere onto a plane is obtained. For each point on the surface, a ray from the north-pole through this point is constructed. The intersection of the ray with the plane is the projected point (use R to make this ray visible).. If you enter a complex function, it is pulled back through the stereographic projection

Stereographic projection globe | IMAGINARY

Learning Geology: Stereographic projectio

Define the stereographic projection of P to be this point P' in the plane. In Cartesian coordinates (x, y, z) on the sphere and (X, Y) on the plane, the projection and its inverse are given by the formulas. In spherical coordinates (φ, θ) on the sphere (with φ the zenith angle, 0 ≤ φ ≤ π, and θ the azimuth, 0 ≤ θ ≤ 2 π) and polar coordinates (R, Θ) on the plane, the projection. stereographic projection ( plural stereographic projections ) (projective geometry, complex analysis, cartography) A function that maps a sphere onto a plane; especially, the map generated by projecting each point of the sphere from the sphere's (designated) north pole to a point on the plane tangent to the south pole . quotations

Stereographic Projection - YouTub

I'm trying to understand the proof of the theorem (given in the link) that states Stereographic projection maps circles of the unit sphere, which do not contain the north pole, to circles in the complex plane. Link to the proof. In the proof it states In order to obtain an equation for the projection points (x, y) ∈ C of the circle c under stereographic projection, we substitute (1) into. Stereographic projection was used by the ancient Greeks and probably the Egyptians before them. Ptolemy famously discusses it in his writing, the Planisphaerium (celestial plane or star.

[GIF] Microcosm (Stereographic projection of cube grid

Stereographic projection - YouTub

This Demonstration highlights the properties of stereographic projection. This is achieved by mapping simple geometric shapes from the or plane onto the unit sphere using inverse stereographic projection. The inverse stereographic projection of the point to the unit-sphere is the point . Contributed by: Erik Mahieu (March 2011 3D illustration of a stereographic projection from the north pole onto a plane below the sphere. Part of a series on: Graphical projection; Planar. Parallel projection. Orthographic projection. Multiview projection; Axonometric projection. Isometric projection; Oblique projection; Perspective projection. Curvilinear perspective; Reverse perspective ; Views. 2.5D; Bird's-eye view; Cross section. Other articles where Stereographic projection is discussed: map: Map projections: the Earth's surface, it is stereographic; if from space, it is called orthographic Stereographic projection is a beautiful and important idea, and these models show how it works in an immediately understandable way, says Saul. I think people respond even better to a.

Stereographic Projection, Chaucer and the Astrolab

5-Band Graphic Equaliser. This graphic equaliser uses low-cost op-amps. Good quality op-amps powered by a single voltage supply are readily available in the market. The op-amp should have a noise density of less than 24nV/ VHz, slew rate of more than 5V/µs and gain-bandwidth product greater than 3 MHz. The NE5532 or LM833 used in this circuit. Stereographic projection is a map from the surface of a sphere to a plane.. A map, generally speaking, establishes a correspondence between a point in one space and a point in another space.In other words, a map is a pattern that brings us from one space to another (in this case, the two spaces are a sphere and a plane)

ステレオ投影 - Wikipedi

I have a stereographic projection question for anyone who can help! My lecture notes have an aside about stereographic projection. Definining X to be the angle between the centre of the sphere and the point in R^2, we get that the angle at the north pole is X/2, and some simple trig gives: r = 2 tan (X/2) where r is the radial co-ordinate on the plane (assuming the sphere is a unit sphere). My. Above these plates rotates a celestial map (rete), in stereographic projection too, with star-pointers and the eccentric ecliptic circle. astrolabe.ch. astrolabe.ch. Die Vertiefung der mater dient zur Aufnahme der Einlagescheiben sowie der darüber drehbar angebrachten Sternkarte (rete) mit exzentrischem Ekliptik-Kreis und Sternspitzen. astrolabe.ch. astrolabe.ch. Description of the classical. gsn_csm_contour_map_polar is the plot interface that draws a contour plot over a polar stereographic map. A Python version of this projection is available here . polar_2.ncl: Adds some intrinsic labels, manually sets the contour values, and creates a panel plot. cnLevelSelectionMode = ManualLevels. cnMinLevelValF = -10

Stereographic polar zenithal projectionPolar Stereographic Projection and Grid | National SnowStereonet: measuring the angle between two planes - YouTubemedium scale digital vector Gall Stereographic world mapFile:Europe polar stereographic Caucasus Urals boundary

The best stereographic projections use a type of picture called a 360-degree panorama. This means that the edge of one side of the panorama could be placed next to the opposite edge of the panorama and the two sides would form a continuous scene. These types of pictures are often created by standing in one place and taking continuous photographs while panning the camera in a 360-degree circle. single-chip high-brightness projections up-to-date input capabilities & future-proof design; full operational flexibility through wide lens range; Find out more. Download drivers, firmware & software updates. Blog Interview with INSEAD CIO, Choo Tatt Saw - What should IT leaders know when adopting purp... 11 September 2021. Read blogpost. News Built for speed: Barco demonstrates 240Hz frame. I don't know how to handle this Engineering question and need guidance. Draw a standard (0001) stereographic projection of beryllium (hexagonal, c/a=1.57), showing all poles of the form , , , and the great circles and . If the c/a is changed to 1.7 2, using different symbol to draw the new position for poles on the same projection If the WKT string specifies Stereographic then it should indeed be recognized as such, especially since it is valid WKT. This causes a problem in the netcdf driver with the CF Stereographic projection, as ObliqueStereographic? is not recognized. The PROJ.4 representation is not as well defined. Here is how it should be (I think) Stereographic Projections, created from equirectangular panoramas using either Hugin or Flexify