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Optical differences between 42s SLC 'neu' and final production (1 Viewer)


Well-known member
This might be hard to answer as I'm comparing a 7x neu (=new) model with the latest, just discontinued 8x and 10x models.

Is it possible to find out what changes or improvements were made in the SLC x42 line between my final production 7x42 SLC and the restyled final production 8 and 10x42.

The 7x42 is very highly regarded - and also quite heavy. The other two are also highly regarded but lighter, with the 10x in particular being lighter and shorter by a small amount than the 8x. As an aside, all three are among the most reassuringly solid and comfortable binoculars to my taste.

Somehow the look of the view seems different with the 7x, leaving aside the obvious difference in magnification. I can't explain what it is, so any facts about changes in colour, types of glass and coatings used and so on would be great to know. For what it's worth none of them has competitive close focusing and that doesn't worry me.

Thank you,

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Experienced observer
United States
The newer SLC models have HD glass, the Neu does not, so they should be better with chromatic abberation.
The SLC Neu models have some of the best and similar lens coatings, and all have dielectric prism coatings,
so that part should be similar.

The SLC Neu models are very good, I have experience with several.


John A Roberts

Well-known member
For an overview . . .

The original x42 SLC was introduced in 1992 in 7x42 and 10x42. Both remained in production until 2010, when the all new x42 SLC was introduced in 8x42 and 10x42

In relation to what’s known about the optics:
• The original design had an objective of 3 elements in 2 groups (1 + 2 focusing); and an eyepiece of 5 elements in 3 groups (2 + 1 + 2)

• The current design has an objective of 4 elements in 3 groups (1 + 2 + 1 focusing); and an eyepiece of 5 elements in 3 groups (2 + 2 + 1)

And as Jerry indicates, the new model includes HD glass - it’s the third lens in the objective group
(see Clay Taylor of Swarovski in the post of 9th October 2013 at: http://www.opticstalk.com/differences-between-swarovski-slc-and-el-binocular_topic38579_page1.html )

The more complex pattern objective of the 2010 model is also used on other current models:
the EL Swarovision of 2010, the EL Range of 2011, the x56 SLC of 2013, and the recently released NL

- - - -

In terms of coatings:
- Swarobright dielectric prism coating was introduced on the 7x42 by September 2000 (not on #D7027 61277, on #D7033 62504),
and on the 10x42 by February 2001 (not on #D7039 65033, on #D7103 70724) *

- Swaroclean low friction external lens coating was introduced by September 2007 (not on #D7708 56693, on #D7734 61825) *

- And at the start of 2009, the Swaroclean anti-reflective coatings were updated on all product lines to the current ‘paper white’ version
(see post #29 by Dale Forbes of Swarovski at: https://www.birdforum.net/showthread.php?t=155446 )

* The presence of Swarobright and Swaroclean is not indicated on the units but was marked on the box labels at the times of introduction
The dating is based on my observation of the labels

- - - -

The neu style body covering was introduced on all of the SLC line from the start of 2005 (from #D7501 xxxxx), and is the last style used on the original SLC’s
For an intending purchaser, it’s a convenient visual indicator of the presence of Swarobright. The multi layer coating results in a less yellow image than the earlier silver coating,
which was deficient in the blue portion of the spectrum

See an image from the current SLC catalogue (which can be found at: https://aa.swarovskioptik.com/customer_service?contentid=10007.466400 )
It shows the various coverings from front to rear:

2013 x42 SLC - current version of the new model (all-over two texture rubber covering - although the image seems to show two colours, it's all the same colour)

2010 x42 SLC HD - all new model (forrest green with blackened exposed metal in the bridge area)

2005 x42 SLC neu - last version of the original model (forrest green with black rubber in the bridge area)

1997 x42 SLC - upgraded covering (it lacks the ‘shoulders’ of the original covering, also either green or black)

1992 x42 SLC - the original model and covering (either green or black)



  • Original SLC x42.jpg
    Original SLC x42.jpg
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  • SLC HD x42.jpg
    SLC HD x42.jpg
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  • SLC x42 coverings progression.jpg
    SLC x42 coverings progression.jpg
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Well-known member
Thank you, Jerry and John; much appreciated. I feel very fortunate with these SLCs as they tick so many boxes. Every day that I use this 7 it feels like I have something rare and little appreciated at large, though of course in present company they are far from unappreciated. They are really growing on me. I can almost sense the absence of HD glass compared with the others but only in immediate comparison, not when out of the house using them properly.

Not having got the hang of the various Swarovski numbering systems, John, do you mind reminding me of the date of manufacture of the 7x42 SLC Neu no. D801384600, as I'm interested to work out how close to final production it was made? It has been well looked after and came to me with all its bits and pieces in the box. You remember it was a number you had noted down but I can't now trace the thread you mentioned it in. (Sorry!) As for the weight, I'm quickly getting used to it and it balances excellently and has great grippability. As do the other 42s of the last of the line series.

Best wishes,



Experienced observer
United States
The number you show says the year of mfr. for the SLC Neu is 2010, you find that by adding the number
30 to the first 2 digits of the ser. #. 80 +30= 2010.
That means it is a late production, and among the last of the model series.

Enjoy in good health.



Well-known member
The 42 mm SLC HDs and their successors were completely different optical designs from the SLC Neu and their predecessors.
A significant difference is that the latest models have a -ve focussing lens (moves towards the objectives when focussing to infinity) and the 7x42 SLC has a +ve focussing lens (moves away from the objective focussing to infinity). This is also one of the differences between the original EL (+ve.) and the EL SV (-ve.).
One cannot say that one or the other principle is superior. The 42 mm Zeiss SFs also have +ve. focussing lenses.



Well-known member
Not been looking on here for a while but meanwhile thanks, Jerry, John, and Richard.

I just need to get used to the extra weight of the 7x42 SLC and here I mean when actually holding them in use rather than carrying round. Not much heavier and not a problem but it is about the only thing that I'm not so keen on compared with a comparable spec from the other makers. That and no detents for the eyecups.

But if that is all I have to complain about my verdict is I'm lucky..

(I have come to like SLCs 42s over say 8.5 EL 42 more and more, which is quite an achievement but obviously just personal and to do with flat field, I think.)

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