How to insert an image into the post but skip it from gallery

Hi!
I’m building a site and I need to have a gallery (yes with that jquery popup thingie) appear in one place and set of other pictures in the other.
But when I upload that pictures using insert image within post edit page they automatically go to the gallery.
I thought there could be checkbox “exclude from gallery” but I didn’t find it.

So I’m looking for easy way (customer-friendly) to insert pictures into the post but skip them from appear in gallery.