Kern Macro-Switar 50mm f/1.9 AR
Kern · Alpa · 1968 · Apochromat, 8 elements in 5 groups (Tahusa)
Also known as: Kern Macro-Switar 50mm f/1.9 · Macro-Switar 1.9/50 · Kern-Macro-Switar AR 1:1.9 f=50mm · Kern Aarau Macro Switar 50/1.9 · Macro Switar 50mm 1.9
Variants & identification
| Variant | Mount | Years | Serial ranges | Production |
|---|---|---|---|---|
| Macro-Switar 50mm f/1.9 AR | Alpa | 1968 | — | Unpublished for the Alpa mount; 83 in M42 screw mount (Tahusa, Seawood) |
- Eight elements in five groups: Tahusa's count, confirmed by The Lens DB. Tom Grill describes the 1968 lens only as a redesign with improved coatings and f/1.9.
- The 83 M42 lenses are the only production number anyone gives; the Alpa-mount run — the great majority — is unpublished.
How to tell them apart
- Black barrel where the f/1.8 was chrome; 1:1.9 on the bezel
- Golden-purple coating against the f/1.8's golden yellow (Tahusa)
- Visifocus depth-of-field dots, as the Macro-Switar f/1.8
- Macro-Switar 50mm f/1.9 AR: Black paint only, golden-purple coating, 280 g, nine blades, focus to 0.28 m (The Lens DB; Tahusa says 28.5 cm) — 1.8× magnification at 11 inches by Tom Grill's measure. Visifocus scale with orange dots (Seawood) or yellow (Grill). A gold-plated version exists for the gold 10d and 11si.
Specifications
- Formula
- Apochromat, 8 elements in 5 groups (Tahusa)
- Construction
- 8 elements / 5 groups
- Aperture range
- f/1.9–f/22
- Min. focus
- 0.28 m
- Weight
- 280 g
- Years manufactured
- 1968–1990
- Country
- Switzerland
- Coating
- Single-coated, golden purple
What reviewers say
- Anson (Tahusa), Kern Macro-Switar AR 50mm f/1.9 (blog) — Historically significant Swiss craftsmanship rather than revolutionary optics: "smooth and buttery" bokeh and the Visifocus yellow dots, against a very long manual throw and no macro range on a rangefinder without an EVF.
- Graham Law (Seawood Photo), 'Rare Lens Review' (blog) — A dealer's page: sharp throughout the frame including the corners, "beautiful and smooth" bokeh for portraits, 28 cm at 1.8× — "if I had to pick just one lens to carry around this would probably be my first choice." Nearly three rotations to focus, and vintage contrast that wants adjustment. single source, unconfirmed
History
In 1968 Kern redesigned the Macro-Switar. The new lens has eight elements in five groups where the old had seven, a fractionally smaller maximum aperture of f/1.9, coatings that shift from golden yellow to golden purple, and a black-painted barrel — there is no chrome f/1.9. It keeps the Visifocus depth-of-field dots and the long helical to 28.5 centimetres, and it served the Alpa 10d and the whole 11 series to the end of the company. A small run of 83 was made in M42 screw mount, which is why one is occasionally seen on something other than an Alpa.
The reviews are of adapted lenses on modern bodies, which is how most are used now. Tahusa finds the bokeh “smooth and buttery” and the craftsmanship the point, rather than any revolutionary optical performance; Seawood, a dealer, finds it sharp to the corners and would carry it if allowed one lens; both mention the focus throw of nearly three turns. Production in Alpa mount has never been published.
This history is AI-written, from the sources listed at the foot of the page. Where the record is silent it says so rather than filling the gap — but no human wrote these sentences.
Example photos
Sample photo wanted — shot with a Kern Macro-Switar 50mm f/1.9 AR? We'd love to feature it (with credit).
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