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Calculation of composite focal length (1 Viewer)

musti

Well-known member
I founded from Nikon site next
[Composite focal length] = [Magnification of eyepiece] x [Focal length of DSA-N1 (18mm)]
(35mm format equivalent focal length is 2.7x of the composite focal length)

I will have Swarovski ATX 30-70x95 and swarovski tsl apo 23mm.
If I put Nikon 1 camera to my scope, shall the focal length will be:

At min
30 x 23 x 2.7 = 1863 mm ( 35mm format equivalent )

At max
70 x 23 x 2.7 = 4347 mm ( 35mm format equivalent )

Are my calculation right or shall it be some possibility to error.
 
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