custom post types and category archives

I’m using Custom Post Types UI.

I have a custom post type name Artists. I also have several categories. My category.php page has a custom loop which is set to display all types of posts (&post_type=any)

When I click on a category like Ceramics, no artists will show on the archive page (“Sorry, no posts matched your criteria”) UNLESS there are regular posts that are also in that category. In other words, if the category Ceramics only contains artists, then no posts will display on the category page. If the category contains posts, or a mix of artists and posts, they will all display.

Is there a setting that I’m missing that will allow Artists to appear on the category page?

Thanks!