The Thread
37 lenses · 3 manufacturers · 4 documents
M42 is a thread, not a brand. Nobody owns it, nobody licensed it, and for forty years companies in a dozen countries cut the same 42 mm screw and sold whatever they liked behind it. That is what makes it the largest pool of adaptable glass there is — and it is also why this page cannot be a catalogue. There is no manufacturer to ask.
Why these lenses and not others
A lens is here because a document its manufacturer issued or published was reachable, and legible, and said so. It is not here because it is good, common, cheap or famous.
Three manufacturers are represented: Asahi Optical, KMZ and LZOS. Carl Zeiss Jena, Meyer-Optik Görlitz and Pentacon are absent — not because their lenses are lesser, but because no document they issued could be found. Their absence is the most misleading thing about this list and it is stated first.
Every figure is the maker's own published number. Nothing here is measured, tested or verified by us, and a works acceptance minimum is not a measurement of the lens in your hand.
Variants are separate rows. Two lenses with the same name on the barrel are two rows if two documents describe them, and their numbers differ.
Where two makers, or one maker's two pages, disagree, both figures are shown. We do not pick.
A blank cell means the document did not print it. It never means zero, and it never means we could not be bothered.
The documents span 1970 (an Asahi catalogue) to 2006 (LZOS's own shop pages). They are snapshots of what the maker said then, not descriptions of a production run.
V-SIGNED by Codex — issue #106, attempt 2, 2026-09-19
Generated by a Claude subagent and verified independently by Codex, which is a different vendor, as the workspace rule requires. The first attempt FAILED on two blocking defects; those were corrected and the corrected artifact passed.
Asahi Optical · 24 lenses
One document: the full-line Takumar catalogue Asahi printed in April 1970, in French, in Holland. A sentence beneath the table states that every lens in it is a 42 mm screw thread, which is the maker calling the whole page M42 rather than us deciding it was.
| Lens | Focal · max ap. | Min ap. | Elements | Diaphragm | Angle | Min focus | Weight | Filter |
|---|---|---|---|---|---|---|---|---|
| Super-Takumar Fish-Eye 17mm f/4 | 17mm f/4 | 22 | 11 | EA | 180 ¹° | 0.2 m | 228 g | BI |
| Super-Takumar 24mm f/3.5 | 24mm f/3.5 | 16 | 9 | EA | 84° | 0.25 m | 247 g | 58 mm |
| Super-Takumar 28mm f/3.5 | 28mm f/3.5 | 16 | 7 | EA | 75° | 0.4 m | 218 g | 49 mm |
| Super-Takumar 35mm f/2 | 35mm f/2 | 16 | 8 | EA | 62° | 0.4 m | 242 g | 49 mm |
| Super-Takumar 35mm f/3.5 | 35mm f/3.5 | 16 | 5 | EA | 63° | 0.45 m | 152 g | 49 mm |
| Super-Takumar 50mm f/1.4 | 50mm f/1.4 | 16 | 7 | EA | 46° | 0.45 m | 230 g | 49 mm |
| Macro-Takumar 50mm f/4 | 50mm f/4 | 22 | 4 | PS | 46° | 0.208 m | 265 g | 49 mm |
| Super-Macro-Takumar 50mm f/4 | 50mm f/4 | 22 | 4 | EA | 47° | 0.234 m | 248 g | 49 mm |
| Super-Takumar 55mm f/2 | 55mm f/2 | 16 | 6 | EA | 43° | 0.45 m | 215 g | 49 mm |
| Super-Takumar 55mm f/1.8 | 55mm f/1.8 | 16 | 6 | EA | 43° | 0.45 m | 215 g | 49 mm |
| Super-Takumar-Zoom 70~150mm f/4.5 | 70~150mm f/4.5 | 22 | 14 | EA | 16~35° | 3.5 m | 1209 g | 67 mm |
| Super-Takumar 85mm f/1.9 | 85mm f/1.9 | 16 | 5 | EA | 28° | 0.85 m | 350 g | 58 mm |
| Bellows-Takumar 100mm f/4 | 100mm f/4 | 22 | 5 | PS | 24° | 139 g | 49 mm | |
| Super-Takumar 105mm f/2.8 | 105mm f/2.8 | 22 | 5 | EA | 23° | 1.2 m | 290 g | 49 mm |
| Super-Takumar 135mm f/3.5 | 135mm f/3.5 | 22 | 4 | EA | 18° | 1.5 m | 343 g | 49 mm |
| Super-Takumar 135mm f/2.5 | 135mm f/2.5 | 22 | 5 | EA | 18° | 1.5 m | 444 g | 58 mm |
| Super-Takumar 150mm f/4 | 150mm f/4 | 22 | 5 | EA | 16.5° | 1.8 m | 324 g | 49 mm |
| Super-Takumar 200mm f/4 | 200mm f/4 | 22 | 5 | EA | 12.5° | 2.5 m | 550 g | 58 mm |
| Tele-Takumar 200mm f/5.6 | 200mm f/5.6 | 22 | 5 | PS | 12° | 2.5 m | 370 g | 49 mm |
| Tele-Takumar 300mm f/6.3 | 300mm f/6.3 | 22 | 5 | PS | 8° | 5.5 m | 729 g | 58 mm |
| Super-Takumar 300mm f/4 | 300mm f/4 | 22 | 5 | EA | 8° | 5.5 m | 946 g | 77 mm |
| Tele-Takumar 400mm f/5.6 | 400mm f/5.6 | 45 | 5 | M | 6° | 8 m | 1300 g | 77 mm |
| Takumar 500mm f/4.5 | 500mm f/4.5 | 45 | 4 | M | 5° | 10 m | 3500 g | 49 mm |
| Tele-Takumar 1000mm f/8 | 1000mm f/8 | 45 | 5 | M | 2.5° | 30 m | 5500 g | 49 mm |
KMZ and LZOS · 13 lenses
Two makers, on their own pages, printing an entirely different set of things: vertex focal distances, resolving power under technical specifications (ТУ), transmission and scattering coefficients. Neither origin answers from here any more, so the pages came through an archive — a host, not a source.
| Lens | Focal length | Rel. aperture | Angle | El./gr. 12/13 | Min focus 11/13 | Mass, as printed | Transmission | Resolving power (ТУ) 11/13 | Mount thread |
|---|---|---|---|---|---|---|---|---|---|
| Гелиос-44 | 58 мм (58,60 мм) | 1:2 | 40°28' | 6/4 | 0,5 м | 0,23 кг | 0,82 | 38/20 линий/мм | M42x1 |
| Гелиос-44 | 58 мм (58,60 мм) | 1:2 | 40°28' | 6/4 | 0,5 м | 0,35 кг | 0,80 | 36/17 линий/мм | M42x1 |
| Гелиос-44 | 58 мм (58,60 мм) | 1:2 | 40°28' | 6/4 | 0,5 м | 0,3 кг | 0,80 | 38/19 линий/мм | M42x1 |
| Гелиос-44 | 58 мм (58,60 мм) | 1:2 | 40°28' | 6/4 | 0,5 м | 0,3 кг | 0,85 | 41/20 линий/мм | M42x1 |
| Гелиос-44 | 58 мм (58,60 мм) | 1:2 | 40°28' | 6/4 | 0,5 м | 0,27 кг | 0,85 | 41/20 линий/мм | M42x1 |
| Гелиос-44 | 58 мм (58,60 мм) | 1:2 | 40°28' | 6/4 | 0,5 м | 0,27 кг | 0,90 | 45/25 линий/мм | M42x1 |
| Гелиос-44 | 58 мм (58,60 мм) | 1:2 | 40°28' | 6/4 | 0,5 м | 0,27 кг | 0,90 | 50/30 линий/мм | M42x1 |
| Индустар-61М | 50 мм (52,42 мм) | 1:2,8 | 46° | 4/3 | 0,42 м | 260 г | 0,85 | 45/28 лин/мм | M42x1 |
| Юпитер-9 | 85 мм (84,46 мм) | 1:2 | 28° | 7/3 | 0,8 м | 400 г | 0,75 | 30/18 линий/мм | M39x1, байонет, M42x1 |
| Мир-1 | 37 мм (37,38 мм) | 1:2,8 | 60° | 6/5 | 0,7 м | 200 г. | 0,78 | 45/23 линий/мм | M39x1, M42x1 |
| Таир-11А | 133 мм (133,2 мм) | 1:2,8 | 18° | 4/3 | 1,2 м | 600 г | 44/24 | А (M39x1 и M42x1) | |
| Юпитер - 9 | 85 | 1:2 | 28,5 | — | — | 0,380 кг, не более | 0,85 | — | М42 х 1 |
| Индустар - 61 Л/З | 52,42 | 1:2,8 | 46 | — | 0,225 кг, не более | 0,92 | — | М42 х 1 |
Why there are two tables and not one
The two document families share exactly 2 field names: angle_of_view, minimum_focus_distance. They have more than that in common as concepts — at least six, since focal length, maximum aperture, minimum aperture, angle, minimum focus and weight are stated by both, and Asahi and KMZ both give an element count. Different encodings are not evidence that two documents lack the same idea, so that is not the reason for two tables.
The reason is that the shared ideas are stated under different conditions and in different units. Asahi puts focal length and maximum aperture in one cell and gives weight in plain grams. LZOS gives a mass in kilograms qualified не более — a maximum rather than a measurement. KMZ states resolving power under technical specifications (по ТУ), a condition with no counterpart in a Western sales catalogue. A single grid would line those up as though they answered the same question under the same conditions. They do not, so the page does not.
The documents
Every figure above is the maker's own published number, read off a document the maker itself issued. The site hosting that document is named separately, because a host is not a source.
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ASAHI OPTICAL CO., LTD — LES OBJECTIFS TAKUMAR (17 mm-1000 mm) · 63008 - Avril 1970
printed sales catalogue, 23 pages, scanned to PDF
HIGH for the specification table. Rendered at 450 dpi the table is a clean offset-printed grid; every cell in every row was read from the page image.
Warning. The PDF's OCR TEXT LAYER IS NOT RELIABLE and must not be parsed. It renders the 55mm f/1.8 row's minimum aperture as 't0' and its weight as 'ttc', and reads 'f/1.8' as 'l/1.8'. Every figure in this file was read from the rendered page image, not from pdftotext.
Hosted by cameramanuals.org — host, not source
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Asahi Optical (named in the body text; no separate colophon was found in this scan) — (untitled product and price listing; section heads read 'SMC TAKUMAR LENSES (SCREW MOUNT, SUPPLIED WITH CASE)')
printed dealer product/price listing, 33 pages, scanned to PDF
MEDIUM. A poorer scan than the 1970 catalogue; the OCR mangles codes and prices. Read for WHAT IT LISTS, not for figures.
Hosted by cameramanuals.org — host, not source
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НТЦ ОАО "Красногорский завод им. С.А. Зверева" (the Scientific-Technical Centre of OAO Krasnogorsky Zavod named after S.A. Zverev) — KMZ — Krasnogorsky Zavod -- НТЦ -- Архив -- Объективы (lens archive)
the manufacturer's own web pages, no longer reachable at origin
HIGH. Machine-readable HTML (windows-1251), not a scan. No illegibility to declare.
Hosted by web.archive.org (Internet Archive Wayback Machine) — host, not source
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ОАО "ЛЗОС" (OAO LZOS — Lytkarinsky Zavod Opticheskogo Stekla, the Lytkarino Optical Glass Plant) — internet магазин Optics Group — фотографические объективы
the manufacturer's own online-shop product pages, no longer reachable at origin
HIGH. Machine-readable HTML (windows-1251), not a scan.
Hosted by web.archive.org (Internet Archive Wayback Machine) — host, not source
Examined and declined
A refusal is an answer. These were read far enough to reject, and the reasons are printed because the next person to look will find the same material and think they have found the gap.
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butkus.org/chinon/praktica/praktica_lenses/ — 49 retrievable per-lens PDFs (79 pages) covering Carl Zeiss Jena, Meyer-Optik Görlitz, Pentacon and a Feinmess Bonotar
Why it looked right. A manual archive we are allowed to read, a directory literally named 'm42', and one PDF per lens covering exactly the East German makers this ledger needs. Filenames like cz-biotar-2_58.pdf and m-trioplan-2-8_100.pdf read as factory data sheets. This was by a wide margin the biggest single source found.
What it actually is. Each PDF is a print-to-PDF of a Wayback Machine capture of praktica-users.com — 29 are one page, 13 two, four three and three four; the multi-page ones continue into lens photographs rather than factory data, a fan site that closed around 2012. The Wayback banner and the PRAKTICA-USERS.COM masthead are visible at the top of every first-page image — 49 of 49, checked; continuation pages in the multi-page files are lens photographs and carry neither, so the identifier is per document, not per page. butkus.org's own index page says so in plain words: 'From former Praktica-Users site — Site is gone... All links removed and made into a PDF file'.
DECLINED. An enthusiast site in a PDF wrapper, hosted by an archive we trust for other things. The host being legitimate does not make the document one.
There is NO Carl Zeiss Jena, Meyer-Optik or Pentacon record in this file. Those are among the most sought-after M42 lenses and the ledger currently cannot cover them.
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butkus.org Zenit E / EM English instruction manuals (PDF)
Why it looked right. A camera manual whose SPECIFICATION block names the 58mm Helios f/2 and the 50mm Industar f/3.5 — apparently a maker statement about the Helios.
What it actually is. A re-typed transcription. The PDF's own metadata reads Producer 'Microsoft: Print To PDF', Author 'butkus-64_home'. No page images of the original survive in it, and no issuer imprint appears anywhere in the text. The imperial close-focus figures ('18 inches', '24 inches') and the phrase 'precision-made in Russia' read as an English-market importer booklet rather than a KMZ document.
DECLINED. The issuer cannot be established, so it cannot be attributed to KMZ; and because it is a transcription rather than a scan, its legibility cannot even be assessed.
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allphotolenses.com, pentaconsix.com, scribd, learncamerarepair.com, zachhorton.com
DECLINED on the rule, without being read for figures. This is the class the rule names.
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Internet Archive full-text and metadata search for maker lens catalogues
No maker lens catalogue for any M42 manufacturer is in the Internet Archive's text collections under these searches.
Not established
Absent, not zero. Each of these is a thing this desk went looking for and did not find, which is a different statement from the thing not existing.
- Carl Zeiss Jena — no maker-issued M42 lens document was found anywhere. Biotar, Flektogon, Pancolar, Tessar, Sonnar: all absent.
- Meyer-Optik Görlitz (the original East German works, not the modern revival brand already covered by src/data/meyer-optik-specs.json) — no maker document found. Trioplan, Oreston, Domiplan, Primoplan: all absent.
- Pentacon — no maker lens document found. The only Pentacon documents located are accessory leaflets for eyepieces and prism finders.
- The Japanese M42 makers other than Asahi — Fujica/Fujinon, Yashica/Yashinon, Mamiya-Sekor, Chinon, Ricoh/Rikenon, Petri — were not pursued to a conclusion in this pass. Butkus holds camera manuals for all of them; whether any holds a screw-mount LENS document with a spec table is unknown, not disproved.
- Vivitar, Soligor and the other rebadgers — not pursued, and likely hardest of all, since the point of a rebadger is that the maker's name is not on the product.
- Flange focal distance for the KMZ Jupiter-9 — the page prints four values for the family and assigns none to a variant.
- Which factory built any individual Helios-44 — KMZ names three plants and assigns none of them to a variant or a year.
- Light transmission for the Tair-11A — the page gives a figure for the Tair-11 only.
- Optical construction for the LZOS Industar-61 L/Z — LZOS's table has no such row, and KMZ's 4/3 is for a different lens from a different plant.
- The unit on the Tair-11A resolving-power pair and on the LZOS rows — those print no unit. NOT a general Soviet gap: Helios-44, Industar-61M, Jupiter-9 and Mir-1 all print линий/мм or лин/мм explicitly. Narrowed 2026-09-19 after the #106 V-sign, which found the original wording false.
- Whether kmz.ru, zenit-foto.ru, lzos.ru and komz.ru are reachable from elsewhere. They time out from this network. If a fleet host in another region can reach them, the live sites may carry more than the archived snapshots do.
- ANSWERED 2026-09-19 by the #106 V-sign, and left here because the answer is partial: Ricoh Imaging does publish an official legacy-manual index, including an Asahi-imprinted Spotmatic scan listing 17 SMC-Takumar designations. See successor_source_found_by_the_vsign. It is a later SMC list rather than a specification grid, so it is recorded and NOT harvested; whether Ricoh holds a fuller historical spec document is still unknown.