skybox background is vague,can it change HD

1. A concise explanation of the problem you're experiencing.

2. A minimal code example. If you've found a bug, this helps us reproduce and repair it.

3. Context. Why do you need to do this? We might know a better way to accomplish your goal.

4. The Cesium version you're using, your operating system and browser.

You can definitely create your own SkyBox if that’s what you mean! Just pass your images as Scott describes in this post: