I'm not sure that my copy of canons 100 x 400 L lens is up to par . Is there a test or something that I can do to determine this ? I've looked at many different images from this lens online and some of the shots seem so very clean and crisp .... I'm not able to achieve this level of clarity in my photos ...... Is it my limited knowledge ? or is it the lens
your help would be greatly appreciated ...
Larry 


