Orthographic Projection Tool (PROJ +proj=ortho)

Central meridian +lon_0 (°) -10.00°

Latitude of origin +lat_0 (°) 30.00°

Azimuth at center +alpha (° clockwise from north) 0.00°

Scale factor +k_0 1.000000

Included in PROJ string (added in PROJ 9.5.0). Does not change the D3 preview.

Ellipsoid name +ellps

If +R is set, it takes precedence over +ellps.

Sphere radius (m) +R

When set, overrides +ellps.

Flattening +f

Optional; included in PROJ string. Does not change the D3 preview.

False easting (m) +x_0

False northing (m) +y_0

D3 View Scale (pixels) 250

Preview-only. Not part of the PROJ string.

Layers

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Add Point

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Proj String (Orthographic)

Alias: +proj=ortho

Notes: angles default to degrees (append r to use radians, e.g. +alpha=1.570796r). +k_0, +x_0, +y_0, +ellps/+R, and +f are preserved in the string but do not change this D3 preview.

Docs & flags

Orthographic — perspective azimuthal projection centered on +lon_0, +lat_0. Classification: Azimuthal. Forms: forward/inverse, spherical/ellipsoidal. Defined area: global (one hemisphere visible). Alias: ortho. Domain: 2D. Input: geodetic. Output: projected.

proj-string: +proj=ortho

Before PROJ 7.2 only spherical was implemented. To replicate older results, force a sphere with +f=0.
+k_0 and +alpha added in PROJ 9.5.0.
Corresponds to EPSG:9840 (or EPSG:1130 with k_0 or alpha).

Parameters (all optional): +lon_0 (default 0), +lat_0 (default 0), +alpha (default 0), +k_0 (default 1), +ellps (default GRS80), +R (sphere radius, overrides ellps), +x_0, +y_0, +f (flattening; set 0 to force sphere). Append r to angles to use radians.