Excluding categories from archive but not from tag archive pages

Hi John,

thanks for your reply.
Maybe I didn’t explain clearly what I want to do.

Using the default archive page I only want to show posts of the top level categories and exclude posts of child categories.
I am not sure if tag archive pages use the same archive.php.
Because excluding a child category with Simply Exclude from archives, its posts also stop showing up in its own archive and in tag archive pages. So using Simply Exclude doesn’t seem to be the right solution.

Top Level Category
– – Child Category

On the archive htttp://www.example.com/top-level-category I only want to retrieve the posts of the top level category.
On a page with a tag cloud I have tags from posts of the child category. Clicking on a tag link which should return 5 posts of the child category there are no results.

Is there a filter that makes archive pages only show top level category posts and hides posts of child categories?

Best regards,
Neverlands