How do I delete photos on my iPhone but keep them on my macbook air?

I frequently upload photos from my iPhone onto my macbook air, and then I delete them from the iPhone after disconnecting it from the macbook air. After I delete them on the iPhone, I can no longer find them in the iPhotos library (nor the new Photos app library).

Is there a setting somewhere where I can tell the devices to delete from one (iPhone) but store on another (macbook air)?

Thank you!