Show image location
Making panoramic images
The gnomonic projection
Command line options
This page contains some notes about sharing images, in particular
sharing spherical 360° images on various platforms. Inevitably,
as the platforms are constantly changing these notes will become
Please let me know what’s
unclear, or has become wrong, here, so I can improve this page and
enhance PanGazer to make it easier to share images.
All images saved by PanGazer can be uploaded to ‘social media’ and
other applications just like any other image. Further, some platforms
and applications (including Flickr, Google Maps, and FaceBook) are
able to display spherical panorama images and allow you to pan around
them, like PanGazer.
Applications that can display spherical images typically have size
limits and other requirements for uploaded images (see “Application
requirements” below for specific applications). Assuming you have
an existing spherical panorama (similar to the PanGazer ‘starter’
image – see also Making panoramic images), follow the steps below.
Note that if you want to adjust the colouring, contrast, etc., of
a panorama using some other program then it is best to do that before
starting these steps.
- Set and check the geographical position of the image. If
the image already has its geographical position set (usually true
for drone images) there will normally be a ‘Geo:’ line in the PanGazer
static (bottom-right) status. If not you can manually add it using
Image Geography dialog. Use programs such as
MapGazer or Google Maps to determine or check the coordinates of
- Set North for the image. If the image has North set you should
see compass bearings overlaid at the top of the screen
and the status at top right will show a compass point and bearing
(rather than a heading angle). Note that these displays can be turned
off explicitly or temporarily turned on/off using the Space Bar –
see the General Settings page for details.
If North is not set, you should set it (see the Setting North page
for details). Some platforms require that North be set and others
will probably make use of the information in due course.
- Save the image (with the options of changing its size and
expanding it to a full sphere). To do this, use the Image → Resize
image and save as ... menu option (or press Ctrl-r). This will
open a dialog (see the Saving images page for a screen shot and
more details) in which you can:
- Adjust the size of the image:
In general, drone panorama images are large (typically 20,000 pels
(pixels) wide, or more) and are too large or are unnecessarily detailed
for many applications. It is often wise, therefore, to save the
image at a reduced size – to do this change either the X or the
Y dimension (e.g., set the X dimension to 10000).
- Expand a part-spherical panorama to a full sphere:
Drone panorama images are often limited to around 40° above
the horizon but some applications (e.g., FaceBook) require that the
image be a ‘true sphere’ (provide data for the full 90° above
and below the horizon). PanGazer (in the Window title, for example)
describes a full sphere as ‘360° sphere’ and a part-spherical image
as ‘360° spherical’. In the latter case the Save dialog will offer
a pre-checked option to Expand this 360° image to full sphere before
save; you can un-check this to save the image as-is with just a
When ready to save, click the Save button. Whenever a spherical
image is saved, PanGazer will add Extensible Metadata Platform (XMP)
metadata including the known or default image geography and direction
of view when you saved the image, because many applications require
that XMP metadata.
If the image dimensions were changed or the image was expanded the
saved image will then be opened in a new window so you can check
or modify it; again, see the Saving images page for more details.
The requirements enforced by applications are generally poorly documented
(sometimes inconsistently) and change over time, so please take these
notes as ‘best guess’ – and do please let me know of anything that
Just upload the image saved as described above (with expand to sphere)
using the ‘Upload photo’ icon at top right while viewing ‘You’ (your
photostream). There does not seem to be a size limit.
Just upload the image saved as described above (with expand to sphere)
using the ‘Photo/Video’ button or icon when creating a post. There
now (2022) seems to be a size limit of around 25MB, and in any case
it is worth aiming for that size to reduce upload time. Note also
that Facebook may choose an arbitrary centre point (unrelated to
North, the centre of the image, or the saved view direction – although
the latter is normally used).
Note: 360° images only seem to be recognised by FB in ‘new’
posts; the same image attached to a Reply, or added to a Comment,
etc., is treated as a ‘flat’ image.
- Google Street View and Google Maps
Google Street View and Maps show uploaded images using a small blue
circle on Street View (use the Street View app on a smartphone or
click on the ‘little yellow figure’ while browsing Google Maps).
Once you have contributed an image to Google Street View or Google
Maps, anyone can find it and view it as a 360° panorama.
Google applies a size limit on uploaded images. Various Google
sites describe different limits, but images up to 12,000 pels wide
seem to be acceptable (the image dimensions are shown in the status
area at bottom right of the PanGazer screen). If your saved image
is wider than this try reduction to perhaps X: 10000 first (see
above); if this is too large the image will be ‘rejected by server’
when you upload it – in this case, try a smaller size.
Google Street View and Maps do accept spherical (part-sphere) images
saved by PanGazer. However, the ‘missing’ data above the drone’s
angle of view is shown with a black fill; PanGazer’s algorithm to
expand to full-sphere is usually preferable.
The uploading interface to Google Street View and Maps has changed
several times in recent years. As of November 2021:
- using the Street View app on a phone, click on the camera+/create
icon then ‘import 360° photos’ then use the menu on the resulting
page to choose a source for images. Select the images you would
like to appear on Street View, and then touch ‘Publish’ on each to
upload them. Once processed and published, it can take some days
before they appear on the map. Panoramas published in this way seem
to use the GPS data in the image correctly.
- using a browser, open Google Maps and search for the place (e.g.,
a village name or other feature) where you want to add your image.
Once found, then if it has photos (you may need to click on ‘All’,
or another tab, or an existing marker on the map) there should be
a ‘camera +’ icon; click on that to add your image. If there are
no photos shown there should a an ‘Add photo’ button to click; alternatively,
you might be able to add a new Place. Once you have submitted your
image it may take a day or more for it to be added to the Place.
Note that with this method the photo will be positioned at the selected
Place and the actual GPS information in the image seems to be ignored.
As an example, you can view the PanGazer starter image using
Google Maps: Search for “Bejes, Spain” », click on the ‘little yellow figure’ and
scroll right to 225m due East of the car parking area at the southern
entrance to the village (and about 100m SSW of the church); you should
see a small blue circle. Clicking on the circle should display the
panorama. This upload of the starter image, saved as a sphere,
was done using the Google Street Map app from a mobile phone.
- Twitter and Instagram
These applications do not seem to be able to display 360° spherical
Do let me know of any others that you have tested and that could
be added to this list.