Then I make sure the dish is perfectly aimed at the two ku satellites nearest to perfect true south to make directional gain perfect then adjust the eastern and western satellites to gain directionals; perfectly tune the LNBf for center focus (aimed at middle of dish) and focal length is tuned (and skew) for highest quality using different distances. Bigger dishes have the most adjustment here because they have the most parts that can be placed that each need to be adjusted in or out (distance) from the middle depending on over or under the "perfect" .37 f/d ratio; some bigger dishes print the f/d ratio up to 10" off; a large enough amount for the dish to only gain from half the dish (3 db point of the dish only as the gain; and about 1/3 better signal and quality level's are achieved by experimentation, how to discover fact scientifically is to ask a question, why is my dish doing this good or bad and why it works better is experimentally achieved)...