Hi guys. Sorry bout the newbie questions. May I ask 2 questions...
1) How does the 1/focal length thing works?
I know to acheive reasonably sharp photos w/o handshake, it's advisable to shoot at 1/focal length esp when shooting at telelengths. However, how does the focal length affects the handshake? Eg : Is it becoz of the length of the lens? Or the changing of the Centre of Gravity (CG) of the lens when the lens extends? If it's so, wouldn't one be able to shoot with a Canon 70-200mm L, which doesn't extends when zoomed, at 1/70s instead of 1/200s. Assuming u are using a FF.
2) If one is using a crop version eg: 350D with 1.6x crop factor, why must the new focal length be considered in the 1/focal length rule? Eg: When using a Canon 70-200mm L on a 350D, must I shoot at 1 / (200x1.6=320) s or can I still shoot at 1/200s and acheive similar effect.