That's why I have a difficult time calling myself an artist. I have a hard time drawing things from real life because I don't focus long enough to capture something as it is at the moment. I first capture things with my camera, then I use it as reference to draw it. Free hand, of course. I have ideas I want to put down, but nothing ever matches the vision I see and it frustrates me. I envy that you can draw from your mind. I wish I could. That's why you're so talented. I admire you.
My reference: