For some reason there are relatively well known objects without a picture in Stellarium‘s database. It is a free project, a fruition of many people’s voluntary work, so no offence. It is well documented how to add new pictures on this page but I found no easy way to be productive at this task. Plus, there are some problems one needs to overcome in order to succeed.
There are extension packs, but I didn’t find C38 (NGC4565) in them. I wanted to include this particular galaxy. I wrote this for version 0.15.
In the Stellarium folder (in windows, it is c:\program files\stellarium\nebulae\default) there are two kinds of files. The images themselves, and data files, among them the textures.json file. As the name shows, it is a json file easily editable with a text editor. The images should be 2^k (ie 64, 128, 256, 512, 1024…) pixel size, squared, png files. Do note that the square does not mean one has to limit the field of view: it is not the picture file that holds the aspect ratio information, but the coordinates. (tovább…)