Specifications#
- Brand
- Zenit
- Model
- KM
- Camera type
- DSLR
- Lens mount
- Pentax K
- Sensor size
- 36.0 × 24.0 mm (Full frame (35 mm))
- Crop factor
- 1.00×
Specifications merged from Wikidata and Lensfun. Spot an error? Tell us.
Sensor size compared#
Focal length equivalents & field of view#
Multiply any focal length by 1.00 to get the full-frame field of view. Angles are for a rectilinear lens focused at infinity.
| Lens on this camera | Full-frame equivalent | Horizontal | Vertical | Diagonal |
|---|---|---|---|---|
| 10 mm | 10 mm | 121.9° | 100.4° | 130.4° |
| 12 mm | 12 mm | 112.6° | 90.0° | 122.0° |
| 14 mm | 14 mm | 104.3° | 81.2° | 114.2° |
| 16 mm | 16 mm | 96.7° | 73.7° | 107.0° |
| 18 mm | 18 mm | 90.0° | 67.4° | 100.5° |
| 20 mm | 20 mm | 84.0° | 61.9° | 94.5° |
| 24 mm | 24 mm | 73.7° | 53.1° | 84.1° |
| 28 mm | 28 mm | 65.5° | 46.4° | 75.4° |
| 35 mm | 35 mm | 54.4° | 37.8° | 63.4° |
| 40 mm | 40 mm | 48.5° | 33.4° | 56.8° |
| 50 mm | 50 mm | 39.6° | 27.0° | 46.8° |
| 56 mm | 56 mm | 35.6° | 24.2° | 42.2° |
| 70 mm | 70 mm | 28.8° | 19.5° | 34.3° |
| 85 mm | 85 mm | 23.9° | 16.1° | 28.6° |
| 100 mm | 100 mm | 20.4° | 13.7° | 24.4° |
| 135 mm | 135 mm | 15.2° | 10.2° | 18.2° |
| 200 mm | 200 mm | 10.3° | 6.9° | 12.3° |
| 300 mm | 300 mm | 6.9° | 4.6° | 8.2° |
| 400 mm | 400 mm | 5.2° | 3.4° | 6.2° |
| 600 mm | 600 mm | 3.4° | 2.3° | 4.1° |
| 800 mm | 800 mm | 2.6° | 1.7° | 3.1° |
Depth of field table#
Total depth of field at each subject distance, using a circle of confusion of 30.0 µm (the 0.030 mm full-frame standard scaled by the crop factor). Detailed tables: 24 mm f/1.8, 24 mm f/2.8, 35 mm f/1.8, 35 mm f/2.8, 50 mm f/1.8, 50 mm f/2.8.
| Focal | Aperture | 50.0 cm | 1.00 m | 2.00 m | 3.00 m | 5.00 m | 10.0 m | Hyperfocal |
|---|---|---|---|---|---|---|---|---|
| 22 mm | f/1.8 | 5.3 cm | 22.1 cm | 92.8 cm | 2.24 m | 8.03 m | ∞ | 8.98 m |
| 22 mm | f/2.8 | 8.4 cm | 35.0 cm | 1.56 m | 4.23 m | 34.1 m | ∞ | 5.78 m |
| 22 mm | f/4 | 12.0 cm | 51.5 cm | 2.58 m | 9.74 m | ∞ | ∞ | 4.06 m |
| 22 mm | f/8 | 25.1 cm | 1.27 m | 103 m | ∞ | ∞ | ∞ | 2.04 m |
| 43 mm | f/1.8 | 1.3 cm | 5.6 cm | 22.9 cm | 52.2 cm | 1.48 m | 6.35 m | 34.3 m |
| 43 mm | f/2.8 | 2.1 cm | 8.7 cm | 35.8 cm | 82.1 cm | 2.37 m | 11.4 m | 22.1 m |
| 43 mm | f/4 | 3.0 cm | 12.5 cm | 51.6 cm | 1.20 m | 3.59 m | 22.2 m | 15.5 m |
| 43 mm | f/8 | 6.0 cm | 25.2 cm | 1.09 m | 2.70 m | 11.0 m | ∞ | 7.75 m |
| 73 mm | f/1.8 | 0.4 cm | 1.9 cm | 7.8 cm | 17.8 cm | 50.1 cm | 2.03 m | 98.8 m |
| 73 mm | f/2.8 | 0.7 cm | 2.9 cm | 12.2 cm | 27.7 cm | 78.1 cm | 3.21 m | 63.5 m |
| 73 mm | f/4 | 1.0 cm | 4.2 cm | 17.4 cm | 39.7 cm | 1.12 m | 4.71 m | 44.5 m |
| 73 mm | f/8 | 1.9 cm | 8.4 cm | 35.0 cm | 80.5 cm | 2.33 m | 11.2 m | 22.3 m |
| 120 mm | f/1.8 | 0.1 cm | 0.7 cm | 2.8 cm | 6.5 cm | 18.3 cm | 74.2 cm | 267 m |
| 120 mm | f/2.8 | 0.2 cm | 1.0 cm | 4.4 cm | 10.1 cm | 28.5 cm | 1.16 m | 172 m |
| 120 mm | f/4 | 0.3 cm | 1.5 cm | 6.3 cm | 14.4 cm | 40.7 cm | 1.66 m | 120 m |
| 120 mm | f/8 | 0.6 cm | 2.9 cm | 12.5 cm | 28.9 cm | 81.9 cm | 3.39 m | 60.1 m |
Equivalent aperture#
Exposure is identical at the same f-number on any format; equivalence only describes depth of field and total light.
Night-sky exposure limits#
Longest exposure before stars trail. The NPF rule accounts for pixel pitch and is stricter than the classic 500 rule — use it for pin-sharp stars on high-resolution sensors. (NPF needs a known resolution and is omitted here.)
| Focal length | 500 rule |
|---|---|
| 14 mm (14 mm eq.) | 35.7 s |
| 20 mm (20 mm eq.) | 25.0 s |
| 24 mm (24 mm eq.) | 20.8 s |
| 35 mm (35 mm eq.) | 14.3 s |
| 50 mm (50 mm eq.) | 10.0 s |
Handheld shutter speed guide#
The reciprocal rule uses the equivalent focal length. High-resolution sensors may need one stop faster than this for pixel-sharp results.
| Focal length | No stabilisation (1/equiv. focal) | With 3-stop IS | With 5-stop IBIS |
|---|---|---|---|
| 24 mm | 1/25 s | 0.3 s | 1.3 s |
| 50 mm | 1/50 s | 1/6 s | 0.6 s |
| 100 mm | 1/100 s | 1/13 s | 0.3 s |
| 200 mm | 1/200 s | 1/25 s | 1/6 s |
Lenses for the Zenit KM#
Native Pentax K lenses in our database (170 total). Also adaptable: T-mount (T2), M42 screw mount, Deckel (DKL), Tamron Adaptall, M39 / LTM (Leica thread).
- Samyang 8mm f/3.5 Fish-Eye CS 8 mm
- Samyang 10mm f/2.8 ED AS NCS CS 10 mm
- Laowa 12mm f/2.8 Zero-D 12 mm
- Samyang 14mm f/2.8 AE ED AS IF UMC 14 mm
- Laowa 15mm F/4 Wide Angle Macro 15 mm
- Samyang 16mm f/2.0 ED AS UMC CS 16 mm
- Samyang 20mm f/1.8 ED AS UMC 20 mm
- Samyang 24mm f/1.4 ED AS IF UMC 24 mm
- Samyang T-S 24mm f/3.5 ED AS UMC 24 mm
- Laowa 60mm f/2.8 2X Ultra-Macro 60 mm
- Samyang 85mm f/1.4 IF UMC Aspherical 85 mm
- Samyang 135mm f/2 ED UMC 135 mm
- Sigma 4.5mm f/2.8 EX DC HSM circular fisheye 4.5 mm
- Sigma 8-16mm f/4.5-5.6 DC HSM 8–16 mm
- Pentax smc Pentax-DA Fish-Eye 10-17mm f/3.5-4.5 ED IF 10–17 mm
- Sigma 10-20mm f/3.5 EX DC HSM 10–20 mm
- Sigma 10-20mm f/4-5.6 EX DC 10–20 mm
- Sigma 10mm f/2.8 EX DC Fisheye HSM 10 mm
- Tamron SP AF 10-24mm f/3.5-4.5 Di II LD Aspherical (IF) 10–24 mm
- Pentax HD Pentax-DA* 11-18mm f/2.8 ED DC AW 11–18 mm
- Tamron SP AF 11-18mm f/4.5-5.6 Di-II LD Aspherical (IF) 11–18 mm
- Pentax smc Pentax-DA 12-24mm f/4 ED AL IF 12–24 mm
- Sigma 12-24mm F4.5-5.6 II DG HSM 12–24 mm
- Sigma 12-24mm f/4.5-5.6 EX DG Aspherical HSM 12–24 mm
- Pentax smc PENTAX-DA 14mm F2.8 ED[IF] 14 mm
- Sigma 14mm f/2.8 EX 14 mm
- Sigma 14mm f/2.8 EX Aspherical HSM 14 mm
- Sigma 14mm f/3.5 EX 14 mm
- Pentax HD Pentax-D FA 15-30mm f/2.8 ED SDM WR 15–30 mm
- Pentax smc Pentax-DA 15mm f/4 ED AL Limited 15 mm
- Sigma 15-30mm f/3.5-4.5 EX DG Aspherical 15–30 mm
- Sigma 15mm f/2.8 EX DG Diagonal Fisheye 15 mm
- Pentax HD Pentax DA* 16-50mm f/2.8 ED PLM AW 16–50 mm
- Pentax HD Pentax-DA 16-85mm f/3.5-5.6 ED DC WR 16–85 mm
- Pentax smc Pentax-DA 16-45mm f/4 ED AL 16–45 mm
- Pentax smc Pentax-DA* 16-50mm f/2.8 ED AL IF SDM 16–50 mm
Similar cameras#
Other Full frame (35 mm) cameras from around the same time.
- Canon EOS-1Ds 2002
- Sony Alpha 900 2008
- Leica SL (Typ 601) 2015
- Sony α7R II 2015
- Sony α7S II 2015
- Ricoh Pentax K-1 2016
- Canon EOS R 2018
- Nikon Z6 2018
- Nikon Z7 2018
- Canon EOS RP 2019
- Sigma fp 2019
- Sony α7R IV 2019
Frequently asked questions#
What is the crop factor of the Zenit KM?
The Zenit KM has a crop factor of 1.00× relative to 35 mm full frame (diagonal 43.3 mm vs 43.3 mm).
What size is the Zenit KM sensor?
36.0 × 24.0 mm (Full frame (35 mm)), an area of 864 mm² — 100% of full frame.
Is the Zenit KM full frame?
Yes — its sensor is the same 36 × 24 mm size as 35 mm film.
What lens mount does the Zenit KM use?
The Zenit KM uses the Pentax K (flange distance 45.46 mm).
How long can I expose the night sky with the Zenit KM?
With a 20 mm lens (20 mm equivalent) the 500 rule gives 25 s.
Sources & licences#
- Wikidata Q4191385 — CC0
- Lensfun camera database — CC BY-SA 3.0
Last updated October 03, 2026 · How we calculate · Sources