All the Way from Cloud Seeding to Chemtrails

Governments all around the world have always admitted to studying cloud seeding. Since reports of chemtrails have came out, people have been trying to discredit them as conspiracy theorists. Cloud seeding is the same thing as chemtrails, the difference is cloud seeding is done from the ground or the sky and chemtrails are the making of clouds by spraying in the sky. The distinction of the two is very small so why is one considered not a conspiracy and why is the other a conspiracy?