Quote Originally Posted by sedwards View Post
Here is another question then. If i have a crop sensor and shooting 300 mm is 1/320 shutter speed my minimum or should i multiply by 1.6 ?
Yes, the 1/focal length rule is actually 1/"effective focal length" rule - meaning you should multiply the focal length by 1.6 if used on a crop-sensor camera. At 300mm, the minimum shutter speed should be approx. 1/500 sec for sharp images.