When people talk about their glass the first number is the magnification. The last number is the size of the objective lens (the closest one to the "objective" you're looking at).
So a 3-9x50mm means that the scope is variable power (magnification) in the range between 3x and 9x. The significance in the size of the objective is how much light is let in which also makes the sight picture much clearer and more defined. It's hard to understand the difference between sizes and qualities of glass until you go from being used to a Leapers or BSA or something and then jump to a Schmidt and Bender or Swarovski.
Extending the tube another 90mm is meant to act as a sunshade. That's not usually included in the model name stat dealie (ya...it's a technical term) but would be listed in the features. It's optimum efficiency is when it's as long as the glass is wide. In this case, 50mm out from the tip of the glass. Then the only way sun can glint off your lens at an angle is if the sun is visible to your eye through the scope.
Just thought I'd throw that out there.
So a 3-9x50mm means that the scope is variable power (magnification) in the range between 3x and 9x. The significance in the size of the objective is how much light is let in which also makes the sight picture much clearer and more defined. It's hard to understand the difference between sizes and qualities of glass until you go from being used to a Leapers or BSA or something and then jump to a Schmidt and Bender or Swarovski.
Extending the tube another 90mm is meant to act as a sunshade. That's not usually included in the model name stat dealie (ya...it's a technical term) but would be listed in the features. It's optimum efficiency is when it's as long as the glass is wide. In this case, 50mm out from the tip of the glass. Then the only way sun can glint off your lens at an angle is if the sun is visible to your eye through the scope.
Just thought I'd throw that out there.