Filter for the_content and the_excerpt

Hey guys, I’ve got a problem whit the filters.
I added a filter on “the_content” like this:

add_filter(‘the_content’, ‘my_filter’)

And when I use “the_excerpt”, this filter will work.
How can I stop this and make this filter only effect the “the_content” and never effect “the_excerpt”?

Thanks for your attention.