Reading these forums to get more information about what lens i would like to purchase in the future There are still some thing unclear for me, I am wondering this after reading things about the nikon 50 F1.8 D, and the difference between the VR 55-200 vs VR 70-300. One of my big questions is what a fast lens is, why is it fast and why do we want to have faster lenses. Also i maybe need some info on the F value and maybe its related to the fast thing, as far as i know now it has something to do with the amount of light that goes through the lens towards the sensor (wasn't that diafragma also). I did read some where that a teleconverter improves your zoom but also multiplies with that F thing so you get less light on your sensor and that makes sense. Wel since i am asking al my questions now i will ask one more, would you miss the range between the 55 and 70 if you combine the D40 kit lens with the 70-300 VR Namaste and thanks for your reply. Aernout.