Here is the weight breakdown... the 40 = 2lb,1/4oz, 50 = 1lb,12oz (both have the same focusing range and the 40 has approx 10 degrees more angle of view), 80 = 1lb,2oz, 120 = 1lb,8 1/4oz, 150 =1lb,11 1/4oz, 500CM with an A12 and waist level viewfinder = 2lb,2oz.

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