Pattern swatches with a lot of detail may appear very dark in the default “Small Thumbnail View” setting.
![Small Thumbnail View](https://www.halftone.us/content/uploads/2013/12/Screen-Shot-2013-12-16-at-11.16.48-PM.png)
Switching your swatch view to “Large List View” in the swatch library panel menu yields a much more useful preview.
![Large List View](https://www.halftone.us/content/uploads/2013/12/Screen-Shot-2013-12-16-at-11.17.06-PM.png)
Halftone Illustrator, Photoshop & InDesign Patterns & Fills