Featured Image & Slider selection in panel

On my page I have a slider and this page has a thumbnail - this thumbnail shows up on the ‘Archive’ page. The thumbnail is not an image from te slider, but an image i want the user to select. Now in the panel, I want to have to different fields, one for the thumbnail (featured image) and one where the images for the slider are uploaded.

I’m using the selector plugin, but when I make two different fields, and I upload an image in one, it automatically shows up in the other one as well. They basically always include every image uploaded. While I only want the image, that the users uploads in thumbnail is used as a thumbnail.

How can I make that work?

Images are not uploaded to a field, but to a page and are accessible to all fields of the page.

You can however use the filter option of the selector field to filter the images that should be displayed in each field by filename.