Ooops, my mistake, I used 75-300 usm. For that pic I used aproximately 75-100 mm, I was approximately 1,2 m away from the lion. Lately I use my 50 all the time (because I haven't been in the ZOO for a while and 50 is so much better for portraits, which I mostly do besides exotic animals in the ZOO) , so write 50 out of habbit;).
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