|PanGazer – setting North|
When viewing images it is often useful to know where North is in the image; for example, PanGazer will (optionally) overlay compass points on image views if the bearing of the centre of the image is known; this tells you the direction you are viewing.
Further, some applications (e.g., Google Maps and Street View) require that the position of North be known if you use them to share spherical images. It is strongly recommended, therefore, that you set North for any spherical image that you save for other people to view, as otherwise North will be assumed to be at the centre of the image – which will usually be wrong.
Some dedicated-360° cameras (e.g., the Ricoh Theta) record the camera bearing in XMP metadata and PanGazer will use this to set North; in this case, you should normally see compass bearings overlaid at the top of the screen and the status at top right will show a Bearing (rather than Yaw), and you do not then need to set North unless the value is incorrect (perhaps because the camera compass was not calibrated).
However, panoramas constructed from multiple images (e.g., drone spherical panoramas) do not have the image bearing recorded. Even though drones know where they are and which direction they are pointing (and usually record those data), as far as I know no stitching application preserves the direction data.
To have compass directions shown correctly for an image and be saved with the image for sharing, you must identify some point in the image that is due North (True North) of the camera position and then indicate that to PanGazer.
There are two ways to do this:
Once North is set, by either method, the compass points that PanGazer overlays will then move appropriately as you change viewpoint and zoom. You can turn them off or on by clicking the Settings → Overlays → Show compass points menu item (or toggle the display of all overlays and status information using the Space Bar).
When you save the image the North direction will be saved in the Exif metadata and also (for spherical images) in the XMP metadata.
Here is a view showing the compass points overlay (and also the tilt angles overlay); the compass points can only be seen if North has been set:
|PanGazer and these web pages were written by Mike Cowlishaw; Please send me any corrections, suggestions, etc.|
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This page was last updated on 2020-02-18 by mfc.