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Swarovski SL porro models (1 Viewer)

John A Roberts

Well-known member
Hi Swedpat,

That’s an interesting observation about the SL’s lack of reflections around the exit pupil, since the traditional Habicht Porros are poor in that regard
e.g. see the comment and images in Allbinos review of a 10x40 unit: https://www.allbinos.com/112-binoculars_review-Swarovski_Habicht_10x40_W.html

Since the glass is the same, presumedly it was the SL’s novel optical construction that made the difference
(and perhaps the cemented prisms along with caps over them were significant, see the detailed description by Konrad Seil in post #6)



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John A Roberts

Well-known member
SL Numbering and Dating

SL numbering is somewhat complicated, which is why I’ve not addressed it before, but a recent query prompted me to get my notes together . . .

In brief:
A) From their introduction in 1980, SL’s used numeric numbering in what appears to have been various ongoing batch sequences

It seems that a sequence of perhaps 10,000 numbers was reserved for each model in each colour:
- then as production took place, the next numbers were used, but
- a sequence was not always exhausted before a new one was started

However, it also seems that later on an effort was made to go back and use unassigned numbers regardless of the model the batch was initially for
So except where a number is near the starting point for a model, it's questionable when using numeric numbering for dating

B) Then at the start of 1991 Alpha-Numeric numbering was adopted (as it was across all Swarovski product lines), and conveniently the date is in the number:
- add 1930 to the first 2 digits to determine the year, and
- with the expanded version, the next 2 digits indicate the week of the year (01 to 52)

See the attached table which gives more detail


p.s. And as is standard practice, when SONA (Swarovski Optik North America) replaces the part with the original serial number, they assign a new number
It's a 9 digit number in the form 'CAyy nnnnn' where:
- C indicates the original model (C for SL models)
- A indicates SONA replacement (A for America)
- yy indicates the year when the replacement was done (as usual add 1930), and
- nnnnn is the sequential number


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John A Roberts

Well-known member
Laser Filters image (see post #9)

A recent post elsewhere, prompted me to realise that I neglected to include an image of the laser filters that were used in the French Navy units
The green filters are shown next to the objective housings. The image is from the same source as the last one in post #7

- - - -

For another view of a laser filter, see one fitted to the prism assembly of the current Swiss service binocular the Leica Kern 8x30
The image is from Frank’s (aka LPT) Flickr account at: https://www.flickr.com/photos/[email protected]/11127299454/in/photolist-hXhjsA-ec8fn4

And for some more information, see: http://www.eyry.eu/miltec/index.php...litary-binoculars&catid=15&Itemid=198&lang=en



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