Glass Bodies a variant-level encyclopedia of vintage lenses and cameras by iwillpat

Ultron 28mm f/1.9 Aspherical

Cosina Voigtländer · LTM · 2001

single source, unconfirmed

Also known as: Voigtländer Ultron 28mm f/1.9 Aspherical · Voigtlander Ultron 28mm f1.9 · Cosina Voigtländer 28mm f/1.9 Ultron · Voigtlander 28/1.9 Ultron · Voigtlander 28mm 1.9 LTM · フォクトレンダー ウルトロン 28mm F1.9 Aspherical · ウルトロン 28mm F1.9 · L39 · LTM

Variants & identification

Variant Mount Years Serial ranges Production
Leica screw mount (2001) LTM 2001–2007 — —
  1. Formula, aperture range, blades, minimum focus, coupling range, dimensions, weight, filter size, finishes, yen prices and the on-sale and discontinuation months come from Cosina's discontinued-product page. Reviewers' figures differ slightly — 260g and 49mm without hood at phillipreeve.net, 275g and 48mm at KJ Vogelius, who also dates the launch to 2000 against Cosina's April 2001. CameraQuest, the source of the LTM era's US prices, sits behind a Cloudflare challenge and the Internet Archive was unreachable, so no US price is given.
  2. phillipreeve.net alone makes the claim that this remains the fastest 28mm ever built in Leica screw mount; no second source was found for it.
How to tell them apart (expand)
  • Ten aperture blades, f/1.9 to f/22, 75° angle of view
  • Never made in M mount: the M-mount Ultron 28 of 2008 is an f/2 of a different, ten-element design

Leica screw mount (2001):

  • 39mm Leica screw thread, rangefinder-coupled from infinity to 0.7m¹
  • Silver, or black paint at ¥3,000 more¹
  • Engraved ULTRON 28mm F1.9 Aspherical; 46mm filter thread; a dedicated hood that brings the length to 63.1mm on a φ55.8mm barrel, 265g¹

Specifications

Formula
Retrofocus, 9 elements in 7 groups with one aspherical element
Construction
9 elements / 7 groups
Aperture range
f/1.9–f/22
Diaphragm blades
10
Min. focus
0.7 m
Dimensions
55.8 × 63.1 mm
Weight
265 g
Filter
46 mm
Years manufactured
2001–2007
Country
Japan
Coating
Multi-coated
Original price
¥75,000 excl. tax in silver, ¥78,000 in black paint (2001) (today ¥84,000–¥88,000)

What reviewers say

Optical Ratings

Aggregated from the reviews above — follow the links for the full picture.

Spherical aberration
Glow wide open
Vignetting
3.4 EV open
Flare & ghosting
Weak, ghosts
Optical formula — Retrofocus, 9 elements in 7 groups with one aspherical element

History

Two years after the Bessa L and its scale-focus wides, Cosina put a fast lens in Leica screw mount. The Ultron 28mm F1.9 Aspherical went on sale in April 2001 at ¥75,000 excluding tax in silver and ¥78,000 in black paint: nine elements in seven groups, one of them aspherical, a retrofocus design coupled to the rangefinder from infinity to 0.7m, ten blades, f/1.9 to f/22, a 46mm filter thread, and a dedicated hood that brings the length to 63.1mm on a 55.8mm barrel weighing 265 grams. Camera-wiki notes it as unusually fast for a rangefinder lens of this length, and phillipreeve.net goes further, calling it still the fastest 28 ever built in screw mount — a claim no second source here confirms. Cosina’s own words were that the bokeh comes alive and the aspherical element gives sharpness and rich tonality from wide open. It was discontinued in June 2007, and it was never re-mounted: the Ultron 28 that appeared in VM mount in 2008 is an f/2 of a different ten-element design, which is why it has its own page.

The reviews split along a line the lens draws itself. As an optic measured against what came after, BastianK at phillipreeve.net finds good sharpness and contrast from f/2.8, superb ten-pointed sunstars and solid handling, but 3.4 stops of vignetting and a spherical glow at f/1.9, poor corners on a high-resolution sensor, weak flare resistance, field curvature that spoils the bokeh and a small focus shift; new is not always better, he concludes, but sometimes it is. KJ Vogelius reaches the same list from the other side — muted colour and low contrast open, pronounced ghosting, focus shift, a body too big for a screw-mount camera and one that blocks a good part of an M finder — and still calls it an easy recommendation if a fast wide is what is wanted, because it is usable hand-held in very low light and the bokeh is smoother than a fast wide has any right to be. Hamish Gill’s piece is about the buyer rather than the lens: he owned one for nearly a decade, hardly used it, found it too bulky to carry, and replaced it with the 28mm f/3.5 Color-Skopar, which he finds sharper and less prone to flare. Fast and wide, he decided, never crossed paths in how he photographs.

For anyone who does want fast and wide in a screw thread, the checks are ordinary. It needs the 28/90 screw-to-bayonet adapter on a Leica M or a Bessa R2 or R4, where it brings up the 28mm frame on the bodies that have one and then hides a corner of it; on a Bessa R or T it goes straight on, and both want a 28mm finder in the shoe. The hood is part of the design and part of the length, and every reviewer who mentions flare says to fit it. Confirm the aperture ring’s click stops and that the aspherical front element is unmarked, since a cleaning scratch on that surface is the one thing the lens cannot shrug off. And weigh the alternative the reviewers keep reaching for: Cosina’s own f/3.5 of 2002, a third of the weight, which spends its time on the camera.

Expand Collapse

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 Ultron 28mm f/1.9 Aspherical? We'd love to feature it (with credit).

Live listings

Asking price, USD: a median of $580 across 17 fixed-price listings on 2026-09-19 (middle half $480–$720). First day tracked.

Asking prices from the listings scanned, not sales; junk-flagged rows and auction lots excluded; other currencies are not converted.

Show 10 more listings

Listings updated 2026-09-19. Links go to the shop or marketplace that carries the item.

Related: Color-Skopar 28mm f/2.8 Aspherical · Color-Skopar 28mm f/3.5 · Nokton Vintage Line 28mm f/1.5 Aspherical · Nokton 35mm f/1.2 Aspherical · Nokton 50mm f/1.5 Aspherical · Ultron 28mm f/2 · Ultron 35mm f/1.7 Aspherical

Sources (5)

Every page here is assembled from public sources, and the gaps are real ones. If you own this lens, know a serial number I'm missing, or can see where I have it wrong, tell me — corrections, serials and sample photos are all worth having.