This template contains the source files used in the skydome sets, and is intended primarily for creators who would also wants to make them for themselves or community. Inside you'll also find screenshots of Unity Import settings that I consider to be the best for quality and performance.
In addition to 4K and 8K textures, you can use intermediate 6K resolution of 6144x1536 pixels. It's right in the middle in terms of quality and file size, since Unity without CrunchCompression allocates a fixed amount of MB per texture in an .assetbundle file, depending on its pixel size. Because this isn't a Power of Two texture, it will likely be allocated the same VRAM as an 8K texture, but with the difference of a few MB.
Some examples
In addition to 4K and 8K textures, you can use intermediate 6K resolution of 6144x1536 pixels. It's right in the middle in terms of quality and file size, since Unity without CrunchCompression allocates a fixed amount of MB per texture in an .assetbundle file, depending on its pixel size. Because this isn't a Power of Two texture, it will likely be allocated the same VRAM as an 8K texture, but with the difference of a few MB.
Some examples