Eyepiece Strategies for your Hexagonal 2 Turret

The question, "Why don't you create a Hex that will take one 2" and five 1.25" eyepieces?" is asked frequently. So a section on this basic topic will help answer that question, and probably provide a few other answers too.

People are probably thinking of the old Unitron Unihex from many years ago. At one time, Unitron offered a dual format, 6-eyepiece turret that accepted one 1.25" eyepiece and five 0.965" eyepieces. This was feasible because the difference between a 0.965" and a 1.25" eyepiece is about a quarter of an inch. The difference between a 2" eyepiece and a 1.25" eyepiece is three quarters of an inch - 3 times the diameter difference. This increase is the reason a turret with one 2" port and five 1.25" ports would be impractical, at best.

To insert one, or six 2" format eyepieces in a turret, you would still need a turret with a rotating housing profile exceeding the 2" format, like the Hex 2, which has a rotating housing profile of 2.5 inches (see size comparision picture at right). Essentially, to make a turret with one 2" port and five 1.25" ports, you would need to make a turrret with the same dimensions as the Hex 2. So why not just make the Hex 2 and use 2" to 1.25" reducers, such as our AR21, in the 2" ports? Note the left Hex 2 picture, that creates the reality of the above question, one 2" eyepiece and five 1.25" eyepieces, using five AR21 reducers. And, you now have the versatility to install any combination of 2" and 1.25" eyepieces.