I'm NOT a professional photographer - nor do I want to be - I just want to take good photos of my new baby. I borrowed my friends 50mm f1.8 lens the other day and when I shot with it - I was thinking - this isn't really much different than my 18-55mm lens. Then when I went back and looked at my photos - I noticed NOTHING was shot at f1.8 - and it hit me - was I supposed to manually crank the aperture? I assumed it would automatically set to f1.8 because I thought it was fixed... but now I'm guessing maybe not. So am I an idiot??? Did I just totally miss out on it? I may have to borrow it again so I can use it CORRECTLY. I'd love for someone to let me know if I was SUPPOSED to manually crank the aperture to f1.8 or if it was supposed to know. Sorry - i'm a total noob.