Sprite Packer and Sprite Editor

I am new to 2d in Unity, but am confused about the relationship between Sprite Packer and Sprite Editor. I was easily able to make an atlas using Packer, but can’t figure out how to open it in Editor. All of the tutorials for Editor seem to assume you have a preexisting atlas. And I could easily make one using a 3rd party tool, but would rather not.

I am trying to make an animated sprite from a sprite sheet made with Packer. Can anyone point me to useful information on how to do this?

thanks

Hopefully this link should help you with the editor and how to animate your sprites.

http://unity3d.com/learn/tutorials/modules/beginner/2d/sprite-editor

You can also check out ShoeBox. The sprite packer simply creates/packs lots of textures into a single sheet/atlas and within the sprite editor you should load the sprite sheet/atlas and isolate the individual sprites (grid/auto) for you to animate. Hope that helps a bit?