Hi Eitan (post #96),
With 2 exceptions, the optics of the various models in the original series SLC’s did remain the same throughout production
The exceptions were the Mk II upgrade to the 7x30 and 8x30 models in 1989, see post #9 at:
https://www.birdforum.net/showthread.php?t=380550
However, the new SLC’s - the x42’s starting in 2010 and the x56’s in 2013 - are all new designs, including optically
(with the addition of HD glass, and the use of Abbe-Koenig prisms in the x56's)
See the attached image of:
- the original x42 SLC (Objective of 2 groups: 1 + 2 element focuser. Eyepiece of 3 groups: 2, 1, 2 elements)
- the 2010 x42 SLC (Objective of 3 groups: 1, 2 + 1 element focuser. Eyepiece a 3 groups: 2, 2, 1 elements)
- - - -
Hi Xlr8n (post #98),
In 2013, Swarovski increased the minimum close focus distance of the x42 SLC’s by simplifying the focuser mechanism, and at the same time introduced the all over RA covering
However, there’s no indication that the optics were changed. As can be seen from the most recent specification sheet, the x42’s have 11 optical elements per side
So 2 prisms plus 9 lenses, as in the 2010 SLC x42 cutaway view
John