Import your local sky into Stellarium

In order to better plan your observations and astrophotography sessions, here is the presentation of a simple, fast and efficient method for Stellarium to display the 360 ° photograph of your site, very useful in the context of a fixed position but also semi-nomadic in your garden or elsewhere if the location of your mount on your observation site is always precisely the same.

This allows thanks to this great software to:

- choose your object according to your accessibility to the different areas of the Sky

- plan if during your poses during the night the target will not pass behind a tree, a chimney or a house antenna, or any other obstacle, which would have the consequence of rendering the images of the session unusable.

The software has pre-recorded landscapes that you can edit to change the look of Stellarium. To insert your own landscape, with the right orientation, just follow these steps:

- take a 360 ° photo of your site, from there where the imaging equipment is located (with a 360 camera or panoramic assistance software, etc.)

- work this image in Photoshop or Gimp for example

- import the image into Stellarium

- refine the orientation of your landscape so that the cardinal points correspond

1 - TAKE A 360 DEGREE PHOTO OF YOUR SITE:

For this step we are going to use the Google Street view software which makes it easy to create this type of image. Any other method you prefer could be used for this purpose.

Start by installing the Google Street View application on your Smartphone.

Open the application and click on the camera icon then on "take a photo". The application will then access your camera with your permission.

Then you just have to aim with your phone at the orange targets appearing on your screen so that the application automatically takes (no need to trigger the photos they are taken automatically as soon as you correctly point each target) all the images necessary for the reconstruction of the full 360.

To do this, try not to move, do not change the angle with which you hold your phone in your hands, and turn around to reach the different targets that appear on the screen. For example, you can start with a full turn on yourself, then lift the device to the sky and do it one full turn too, then point to the ground and do the full turn until all orange targets have been photographed.

The app will then tell you that all the images have been taken when the shooting progress icon at the bottom of the screen turns green.

The application will then automatically stitch the images into panoramas for a few seconds.

You will find that the image is not perfect and that there may be some overlaps, shifts or the like between the different images of the assemblage which is not (except aesthetically) a problem in itself as long as the landscape is more or less correctly represented.

The quality of the image will be linked in part to your acquisition of the different photos, without moving your place and trying to maintain a constant framing orientation, but also to the reconstitution of the 360 by the application, which is not perfect. and on which we will not be able to intervene.

Once you are satisfied with the image taken, to export it to your pictures you will have to connect to your google account (if necessary create one), then on IPHONE click on the icon "Share" then "Share in private" then "Save image".

On ANDROID it seems that the image is automatically saved in your photos at the end of its automatic assembly.

2 - WORK THE IMAGE IN PHOTOSHOP:

After recovering the image on your computer open it in Photoshop.

Step 1: Resize this image to match the format of landscape images in Stellarium.

To do this go to the Image menu then Image size and resize it to 4096 x 2048 pixels.

2nd step: crop the image using the Quick Selection tool for example, in order to select EVERYTHING except the sky.

The quality of the clipping here will depend on your mastery of the technique and your desire or not necessarily for an aesthetically perfect image, knowing that the objective is to properly select all the obstacles to the shot (antennas, trees, houses ... etc so that they appear well afterwards in Stellarium.

For my part I selected rather roughly the antennas, chimneys, tree foliage etc ... so that they are easily visible then in Stellarium (without having to zoom too much) rather than a perfect and very fine selection which could be s. '' be more aesthetic, but less clearly visible when using Stellarium (for TV antennas notably).

Your cutout selection appears in dotted lines.

Then right click on the image then "Layer by copy" (or shortcut Ctrl + J). A new layer is then created, without the sky, above your initial layer which you can now delete if you are happy with the clipping.

Note that during this step in Photoshop you can also try to improve the image if you notice, for example, shifts between certain parts of the landscape, inevitable due to the technique used to take the photo. at 360 degrees, which would be rectifiable at this stage. Once again a perfect image is not essential and do not rely on the rendering obtained at this stage which is different from the final rendering once the image has been loaded into Stellarium.

3rd step: save this cropped image in PNG format (important) with the name you choose (example: HOME) in a folder that you name for example with the same name.

3 - IMPORT THE IMAGE INTO STELLARIUM:

Start by placing the folder created with your image in it in the destination C: / Programs / Stellarium / Landscapes among the other landscape directories (my folder is called "house" in the following image).

Each landscape is associated with an .ini file which must be placed in the same folder as the photo. To create our .ini file we will simply go to one of the other landscapes folders, it doesn't matter which one and copy the landscape.ini file that we will paste in our own folder next to our photo.

We then open this .ini (which is nothing more than a text file) by double clicking on it then we edit it as follows:

[landscape]

name = name of your image (ex: home)

author = your name

description = your description

type = spherical

maptex = name your image.png (ex: home.png)

angle_rotatez = 0 (we will modify this then to match the cardinal points)

[location]

planet = earth

latitude = your latitude in the format shown in the following image

longitude = your longitude in the format shown in the following image

altitude = your altitude in meters

timezone = Your timezone

For my part I completely deleted the copied / pasted ini file, then fills in with only these indications. I did not keep the criteria which are not essential. Indeed you will see that the ini file contains other variables that you can if you wish to keep and adjust by going to the user manual of Stellarium to know what they correspond to if you wish to be able to use all the features associated with the landscape, This is not my case.

Click on file / save to validate the modifications made to this .ini file

We can now launch Stellarium and then use the shortcut f4 to open the landscape settings.

Select your landscape which should appear in the list on the left. You should then be able to read the coordinates of the place you entered, the name of your landscape and your name.

Check the box "use this landscape by default" then adjust the brightness of your landscape by checking "minimum brightness" and increasing or lowering the value opposite (0.10 here).

Adjust to your liking and so that you can distinguish obstacles in the landscape of night (in my case the landscape must be bright enough so that at night I can discern easily and without having to zoom too much the chimneys, antennas, etc ...)

4 - LANDSCAPE ORIENTATION

Last essential step, we still have to modify the orientation (rotation) of our image so that Cardinal points displayed in Stellarium coincide with the reality of our site of course!

It is unlikely that this will match right away but luckily we just have to adjust the rotation angle of our image by going again to the .ini file and adjusting the value "angle_rotatez" as seen above with a value going from 0 to 360 degrees.

In my case a value of 90 a made it possible to achieve a quarter turn in my image which made the cardinal points coincide almost perfectly. It is up to you to find the rotation value from 0 to 360 degrees by successive trials to reach the desired degree of perfection.

Obviously, each time the rotation angle value is modified, Stellarium must be closed, the value in the ini file modified, the ini file saved, and Stellarium restarted to observe the change in the orientation of the landscape.

On my final landscape you will be able to note that the chimneys, antennas, trees etc ... are crudely cut out, on the one hand in the absence of having perceived a utility to y spend 3 hours :-) to do it properly, but also to be able to visualize them very easily as explained above because the antennas and trees are very little contrasted compared to the night sky.

Having arrived at the end of this manipulation, it is now time to take full advantage of the considerable enjoyment obtained by the 360 degree visualization of your observation site in Stellarium !! :-)

Top of page