Is the lens that came with my XTI a good lense? SHould I invest in another I have the cannon EFS 18-55mm and the 75-100mm.

 

it depends what you plan to do. the stock lens works for me, most of the time, but i wish i had a bit more zoom.
f-stop is still a foreign language to me, so i wont be any help with that. all i know is the lower the f-stop, the higher the price!

 

I heard a lot that the lens is okay for bigginers but it is not that great once you start moving up.

this are better lenses
https://my350z.com/forum/photography/312409-looking-for-a-cheap-canon-is-lens-your-answer-canon-18-55-is.html

 

I'll mess with this untill I need more.