Takumar 50mm f/3.5

Name: Pentax Takumar 50mm f/3.5
Brand: Pentax

32mm filter

Focal length

50mm

Max Aperture

f/3.5

Filter Thread

32mm

Min Focus Distance

76cm

Produced 1952–1957 · medium confidencehttps://takumarguide.weebly.com/m37-takumar-guide.htmlSpans the Takumar Field Guide's three folded models: I May 1952-May 1953, II 1953-1954, III 1954-1957.

Mount: Asahiflex M37 — compatible with all Asahiflex M37-mount bodies.

Zoom

Focus

Manual

Macro

Mount

Asahiflex M37

Format

35mm

Groups

Elements

Filter Thread

32mm

Generation

Models I, II and III folded into this row - see spec Notes

Production

1952-1957

Spec Notes

2+-DIFFERENCE RULE APPLIED - ONE ROW, THREE GENERATIONS. The Takumar Field Guide's Model I / II / III differ by nameplate colour, distance-scale units and (Model I only) focus-ring rotation direction. Its own summary: the three 'are operated manually and differ cosmetically' and 'share the same optical construction; 4 elements in 3 groups'. DIAPHRAGM CONFLICT, unresolved: ja.Wikipedia's lens list and lens-db indicate a manual->preset change, but they place it at different boundaries (I->II vs II->III at Nov 1954), and klassik-cameras states of the whole M37 group that 'All of them have preset diaphragm'. The Field Guide author separately calls all eight M37 lenses 'pre-set' - so his 'operated manually' contrasts with automatic actuation, not with preset. No source assigns a serial or date to either side, and the Field Guide's own model serial ranges OVERLAP (II 356xx-597xx, III 395xx-945xx), so a split could not tell an owner which row their lens is. REVISIT TRIGGER: if a period Asahiflex catalog or manual pins the diaphragm change to a serial or date, re-score I+II vs III. MIN FOCUS: the scale is feet-only, 2.5 ft = 76.2 cm; published metric restatements vary (0.7 / 0.75 / 0.8 m) and are roundings of one figure, not version differences - lens-db, the only source splitting the lens into versions, gives BOTH 0.75 m. APERTURE MIN: f/16 per klassik, allphotolenses, pentaxforums and lens-db Type 2; lens-db Type 1's f/32 is an unverified outlier. WEIGHT OMITTED - 160 g (lens-db) vs 180 g (klassik, allphotolenses, pentaxforums) is an unresolved conflict. BLADES OMITTED - 12 blades is single-source.

Filter Note

slip-on 32 mm accessory diameter, NOT a filter thread

Max Aperture

f/3.5

Min Aperture

f/16

Focal Length

Min Focus Distance

76cm

Focal Length (Max)

50mm

Focal Length (Min)