Originally Posted by TimeOnTarget
Tube Diameter will affect clarity/brightness as there will be less distortion with the larger tube.
I wonder why swaro stated to me that all of the z series used the same glass? Someone didnt know what they were talking about. either the person you talked to or the person i talked to.
I am also not sure where the confusion comes from but there is different glass in the Z6 models. Ilya first noted that in his 2010 SHOT show review. If you go to the Swarovski page you will see that the Z6 has changed to a new version this year "Second Generation" and there are some interesting changes. However, if you go through the general discussion you will see that the discussion of the glass is similar to what Ilya said in that the higher magnification of the Z6 uses HD glass (and they define that). The lower magnification versions of the Z6 lines also use a different set of coatings.
Think about it for a minute. Why would (or could) the cost skyrocket with the higher erector magnification if there were not a difference in components.
Back to the idea of the tube and the advantages of a larger tube. This has been beatern to death in the threads. The erector is not, necessarily, any larger in a larger tube. Its ability to travel is what you gain, not the amount of light that goes through. In some cases, at high magnifications and high zoom, and you need the extra room but the general reason for it is travel. That is why you look for large total travel for scopes that will be taking long shots and that is a larger turret. It is difficult to talk about the erectors because you have to pull the scope apart to really be able to discuss them. In general what you get with the larger tube is more travel.