So a 70 200 lens will let me see how far away roughly ?
I cannot answer. Try not to think of it in terms of how far you can see. All the lens does is bring the subject closer. In all photography with wildlife it really helps if you are as close as possible.But a 70-200 is a very good lens IMO. You can also get a 1.4 converter to fit it and that will nearly take you up to 300 on the top side. That said, you will loose a little light. IMH i would only ever buy canon converters, i have tried sigma and they are not as good and, i think, a waste of cash....good luck..
Thanks its begin