Carl Zeiss Jena Flektogon 20mm f/2.8

We don’t have a vetted photo of this one yet. Own a copy? Send us a packshot and we’ll credit you.

East German multicoated ultra-wide from the second half of the 1970s (sources give 1976–1979 for introduction) that replaced the older Flektogon 20/4. It focuses to roughly 19 cm, giving the exaggerated wide close-up perspective filmmakers like, and it is sharper and more contrasty than the Soviet Mir-20M while still flaring in a vintage way. Six aperture blades; sold as 'auto' and 'electric' M42 variants and later in Praktica B mount.

Key specs

Focal length

20 mm

Max aperture

f/2.8

Mount

M42 screw

Image circle

Full frame

Close focus

0.19 m

Filter thread

67 mm

Weight

350 g

Field of view by sensor

Full frame

84° horizontal · frames like 20 mm on full frame

Super 35

63.8° horizontal · frames like 28.9 mm on full frame

Micro Four Thirds

46.8° horizontal · frames like 41.6 mm on full frame

What it goes on

Auto-aperture M42 lens: use the A/M switch where fitted or a flanged adapter that presses the stop-down pin. Glassless to EF and all mirrorless mounts; the clicked aperture ring is usually declicked for video. Like other late CZJ lenses, the aperture mechanism can get sluggish when old grease migrates, so check the blades snap freely.

• Canon EF camerasWith adapterALEXA 265, ALEXA 35, ALEXA Mini LF, Pocket Cinema Camera 6K G2 +14 more

  M42-EOS flanged ring. Cheap and common. Pick a flanged ring that presses the auto-aperture pin. On full-frame EF DSLRs a few lenses (Helios 44-2, some Takumars) can catch the mirror at infinity.

• Sony E camerasWith adapterRonin 4D-6K, Ronin 4D-8K, Alpha 1 II, Alpha 7 IV +13 more

  Novoflex · K&F Concept · Fotodiox. 27.5 mm of room — a plain mechanical adapter. Manual focus and iris.

• Canon RF camerasWith adapterEOS C400, EOS C50, EOS C70, EOS C80 +10 more

  Novoflex · K&F Concept · Fotodiox. 25.5 mm of room — a plain mechanical adapter. Manual focus and iris.

• L-Mount camerasWith adapterCinema Camera 6K, PYXIS 12K, PYXIS 6K, Ronin 4D-6K +6 more

  Novoflex · K&F Concept · Fotodiox. 25.5 mm of room — a plain mechanical adapter. Manual focus and iris.

• Micro Four Thirds camerasWith adapterMicro Studio Camera 4K G2, Pocket Cinema Camera 4K, Lumix BGH1, Lumix GH6 +1 more

  Novoflex · K&F Concept · Fotodiox. 26.2 mm of room — a plain mechanical adapter. Manual focus and iris.

• Nikon Z camerasWith adapterKOMODO-X 6K S35, V-RAPTOR [X] 8K VV, V-RAPTOR XE

  Novoflex · K&F Concept · Fotodiox. 29.5 mm of room — a plain mechanical adapter. Manual focus and iris.

• Leica M camerasWith adapter· by flange mathsALEXA 265, ALEXA 35, ALEXA Mini LF, Ronin 4D-6K +1 more

  17.7 mm of room for a plain ring. Check rear-element and mirror clearance before buying.

• LPL camerasWith adapter· by flange mathsALEXA 265, ALEXA 35, ALEXA Mini LF, URSA Cine 17K 65

  1.5 mm of room for a plain ring. Check rear-element and mirror clearance before buying.

See every camera this lens fits →

Sources: allphotolenses.com, pentaxforums.com, mflenses.com