Hey!
What’s the real focal length of this scope? In some places I see that’s 518mm, in others 520mm and in others 522mm. What’s more, the magnifications specified in Ricoh’s XW eyepieces webpage http://www.ricoh-imaging.co.jp/english/products/binoculars/scope/xw/index.html) don't help clarify:
XW7 -> 74x
XW10 -> 52x
XW14 -> 37x
The most confusing is XW20 -> 27x. With neither of the focal lengths, 27 is obtained. 518/20 = 25.9, 520/20 = 26 and 522/20 = 26.1.
The same thing happens with the smc PENTAX Zoom XL 8-24mm specs (http://www.ricoh-imaging.dk/da/eyepieces/smc-PENTAX-Zoom-8-24mm-eyepiece.html). With the shortest focal length (8mm) the specs say 63x, but if you divide 518 by 8 you get 64.75.
I know that the differences are negligible, I'm just curious to know what's the real value, and why the depending on the eyepiece, the scope's focal length seems to be different...
Thanks!
Pedro
What’s the real focal length of this scope? In some places I see that’s 518mm, in others 520mm and in others 522mm. What’s more, the magnifications specified in Ricoh’s XW eyepieces webpage http://www.ricoh-imaging.co.jp/english/products/binoculars/scope/xw/index.html) don't help clarify:
XW7 -> 74x
XW10 -> 52x
XW14 -> 37x
The most confusing is XW20 -> 27x. With neither of the focal lengths, 27 is obtained. 518/20 = 25.9, 520/20 = 26 and 522/20 = 26.1.
The same thing happens with the smc PENTAX Zoom XL 8-24mm specs (http://www.ricoh-imaging.dk/da/eyepieces/smc-PENTAX-Zoom-8-24mm-eyepiece.html). With the shortest focal length (8mm) the specs say 63x, but if you divide 518 by 8 you get 64.75.
I know that the differences are negligible, I'm just curious to know what's the real value, and why the depending on the eyepiece, the scope's focal length seems to be different...
Thanks!
Pedro