45.46 mm
Flange focal distance
42.0 mm
Throat diameter
1949
Introduced
SLR
System type
17
Lenses in our database
Mount facts#
- Mount
- M42 screw mount
- Maker
- Zeiss / Pentax / Praktica / Zenit
- Type
- SLR
- Flange focal distance
- 45.46 mm
- Formats
- Full frame
- Electronic contacts / AF
- No (mechanical / manual)
- Production
- 1949–
About the M42 screw mount#
The 42 × 1 mm thread mount of Praktica, Pentax Spotmatic and Zenit — millions of affordable vintage lenses (Helios 44, Takumar, Pancolar).
M42 screw mount lenses#
17 native lenses, widest to longest.
| Lens | Focal | Aperture | Format | Type |
|---|---|---|---|---|
| Laowa 15mm F/4 Wide Angle Macro | 15 mm | f/4 | Full frame | Macro |
| Zeiss Carl Zeiss Jena Flektogon 20mm f/4 | 20 mm | f/4 | Full frame | Ultra-wide prime |
| Tokina RMC Tokina 28mm f/2.8 | 28 mm | f/2.8 | Four Thirds | Standard prime |
| Zeiss Carl Zeiss Jena Flektogon 35mm f/2.4 | 35 mm | f/2.4 | Full frame | Standard prime |
| Pentax SMC Takumar 50mm f/1.4 | 50 mm | f/1.4 | Full frame | Standard prime |
| Pentax Super-Takumar 50mm f/1.4 | 50 mm | f/1.4 | Full frame | Standard prime |
| Voigtländer Color-Ultron 50mm f/1.8 | 50 mm | f/1.8 | Full frame | Standard prime |
| Zeiss Carl Zeiss Jena Pancolar 50mm f/1.8 | 50 mm | f/1.8 | Full frame | Standard prime |
| Zeiss Carl Zeiss Jena Tessar 50mm f/2.8 | 50 mm | f/2.8 | Full frame | Standard prime |
| Pentax Super-Takumar 55mm f/1.8 | 55 mm | f/1.8 | Full frame | Standard prime |
| Zeiss Carl Zeiss Jena 1Q Biotar 1:2 f=58mm T | 58 mm | f/2 | Full frame | Standard prime |
| Zeiss Carl Zeiss Jena Biotar 58mm f/2 | 58 mm | f/2 | Full frame | Standard prime |
| Pentax smc Pentax Takumar 135mm f/2.5 (V2/43812) | 135 mm | f/2.5 | Full frame | Portrait / short tele prime |
| Tokina TELE-AUTO 135mm f/2.8 | 135 mm | f/2.8 | Full frame | Portrait / short tele prime |
| Zeiss Carl Zeiss Jena Sonnar 135mm f/3.5 | 135 mm | f/3.5 | Full frame | Portrait / short tele prime |
| Zeiss Carl Zeiss Jena Triotar-v2 135mm f/4 | 135 mm | f/4 | Full frame | Portrait / short tele prime |
| Pentax Super-Multi-Coated Takumar 400mm f/5.6 | 400 mm | f/5.6 | Full frame | Super-telephoto prime |
M42 screw mount cameras#
Use M42 screw mount lenses on other cameras#
| Adapter | Possible? | Flange gap |
|---|---|---|
| M42 screw mount → Sony E-mount | Yes · manual | +27.46 mm |
| M42 screw mount → Canon RF | Yes · manual | +25.46 mm |
| M42 screw mount → Nikon Z | Yes · manual | +29.46 mm |
| M42 screw mount → Fujifilm X-mount | Yes · manual | +27.76 mm |
| M42 screw mount → Micro Four Thirds | Yes · manual | +26.21 mm |
| M42 screw mount → L-Mount | Yes · manual | +25.46 mm |
| M42 screw mount → Canon EF-M | Yes · manual | +27.46 mm |
| M42 screw mount → Fujifilm G-mount | Yes · manual | +18.76 mm |
| M42 screw mount → Hasselblad XCD | Yes · manual | +27.32 mm |
| M42 screw mount → Nikon 1 (CX) | Yes · manual | +28.46 mm |
| M42 screw mount → Pentax Q | Yes · manual | +36.26 mm |
| M42 screw mount → Samsung NX | Yes · manual | +19.96 mm |
| M42 screw mount → Canon EF | Yes · manual | +1.46 mm |
| M42 screw mount → Nikon F | No infinity focus | -1.04 mm |
| M42 screw mount → Pentax K | No infinity focus | +0.00 mm |
Adapting basics#
A lens can be adapted with simple tube spacers when its flange distance is longer than the camera's. With 45.46 mm, M42 screw mount lenses can in principle go on bodies with shorter flanges such as Praktica B, Canon EF, Canon EF-S, Sigma SA, M39x1, Kiev Automat. Bodies with this mount can take lenses from longer-flange systems such as Nikon F, Leica R, KMZ Zenit DKL-mount, Contax N, Tamron Adaptall, Arri PL, Leica S, T-mount (T2).
Sources & licences#
- Wikipedia: Flange focal distance — CC BY-SA 4.0
- Lensfun mount compatibility data — CC BY-SA 3.0
Last updated October 03, 2026 · How we calculate · Sources