I have camera that has 10x zoom lens. The zoom range is a little short of what I need. I am looking into buying 2.2x telephoto converter. can you tell me how my zoom range will be affected. Will my range be 2.2 * 10 - 20.2x?
The zoom ratio (10x) of the lens will remain the same, though the focal lengths involved will change. If you have (for example), a 10mm-100mm (100/10 = 10x zoom) lens on your camera, the teleconverter will turn this into a 22mm-220mm lens (220/22 = 10x zoom). However, since you can use your lens both with and without the teleconverter, you can effectively double your zoom ratio and make it 20x as long as you attach or remove the teleconverter when appropriate.