When observing the prepared bacterial smears at 1000x magnification, should the iris diaphragm be all the way open or stopped…

When observing the prepared bacterial smears at 1000x magnification, should the iris diaphragm be all the way open or stopped down for minimal light? Why
 
Looking for a similar assignment? Our writers will offer you original work free from plagiarism. We follow the assignment instructions to the letter and always deliver on time. Be assured of a quality paper that will raise your grade. Order now and Get a 15% Discount! Use Coupon Code "Newclient"