The old adage goes that, when hand holding, you should keep your shutter speed faster than the reciprocal of the focal length of the lens. That is pretty simple and easy to remember. My question is how is the affected by the following. 1. Teleconverters - If I am using a 1.4X converter do I need to adjust the shutter speed accordingly? (eg. 200mm + 1.4x = 280mm -> min shutter speed 1/280?) 2. What about cropped sensor cameras - Does the restricted view have the same affect? (eg. 200mm on 1.6 crop factor camera -> min shutter speed of 1/320?) The attached photo has the following specs Canon 50D ISO: 1600 f/ 5.6 300mm (actual focal length) 1/200 sec Thanks for your help.