Yongnuo YN42.5mm F1.7M II 42mm
The 42.5mm focal length (85mm equivalent) and f/1.7 aperture deliver smooth bokeh and low-light capability in a tiny 146g body with STM autofocus. Its discreet, pocketable design integrates unobtrusively on small Micro Four Thirds bodies like the Panasonic G100 or Olympus E-M10 series. This lens is best for street photographers and budget-conscious portrait shooters who need a fast, lightweight prime for everyday candid work and environmental portraits.
Focal length 42mm
Aperture f/22
Mount Micro Four Thirds
Weight 150 g
af type STM stepper motor
lens type prime
35 Overall Score
Price £128
Snapshot
What owners think
How owner sentiment changed over time
ExclusiveBased on when customers actually wrote their reviews - so you can see whether early praise held up.
Owner sentiment has held steady over time
55/100Our AI sentiment read
Based on 9 dated customer reviews, grouped by calendar quarter. Period analysis is in English.
The proof
Performance
Specifications
Full Specifications
Optics
| Type | Prime |
| Focal Length Min | 42 |
| Focal Length Max | 42 |
| Elements | 9 |
| Groups | 8 |
| Coating | Multilayer Coating |
Aperture
| Max Aperture | f/22 |
| Min Aperture | f/1.7 |
| Constant | No |
| Diaphragm Blades | 7 |
Build
| Mount | Micro Four Thirds |
| Format | micro-four-thirds |
| Weight | 0.1 kg / 0.3 lbs |
| Filter Thread | 52 |
AF & Stabilization
| AF Type | STM stepper motor |
Focus
| Min Focus Distance | 300 |
| Max Magnification | 0.15x |
vs Competition
| Spec | Yongnuo YN42.5mm F1.7M II 42mm | Tamron Di III VC 28-300mm f/4-7.1 VXD | Nikon NIKKOR Z DX 16-50mm f/3.5-6.3 VR | Sony E PZ 16-50mm f/3.5-5.6 OSS | Panasonic LUMIX S S-E100 | Canon EF-S 18-135mm f/3.5-5.6 IS USM |
|---|---|---|---|---|---|---|
| Focal Length | 42mm | 28-300mm | 16-50mm | 16-50mm | 100mm | 18-135mm |
| Max Aperture | f/22 | f/4 | f/3.5 | f/3.5 | f/2.8 | f/3.5 |
| Mount | Micro Four Thirds | Sony E | Nikon Z | Sony E | L-Mount | Canon EF-S |
| Stabilization | false | true | true | true | false | true |
| Weather Sealed | false | true | false | true | true | false |
| Weight (g) | 150 | 590 | 135 | 107 | 298 | 515 |
| AF Type | STM stepper motor | VXD linear motor | Stepping Motor | Autofocus | Dual phase linear motor | STM |
| Lens Type | prime | zoom | zoom | zoom | macro | zoom |
| Compare | Compare | Compare | Compare | Compare |
| Product | AF | Bokeh | Build | Macro | Optical | Aperture | User Sentiment | Versatility | Social Proof | Stabilization |
|---|---|---|---|---|---|---|---|---|---|---|
| Yongnuo YN42.5mm F1.7M II 42mm | 86.9 | 13.1 | 90.5 | 37.7 | 51.7 | 20.1 | 3.7 | 33.6 | 60.8 | 36.8 |
| Tamron Di III VC 28-300mm f/4-7.1 VXD Compare | 98 | 77.6 | 65.2 | 85.8 | 96.7 | 65.7 | 91.2 | 97.7 | 56 | 82.4 |
| Nikon NIKKOR Z DX 16-50mm f/3.5-6.3 VR Compare | 86.9 | 75.2 | 92.7 | 45.1 | 74.1 | 77 | 0 | 83.3 | 81.2 | 95.3 |
| Sony E PZ 16-50mm f/3.5-5.6 OSS Compare | 53.8 | 75.2 | 98.5 | 43.9 | 68.3 | 77 | 63.7 | 83.3 | 81.2 | 93.4 |
| Panasonic LUMIX S S-E100 Compare | 98 | 86.8 | 85.8 | 82 | 83.5 | 83.7 | 80.9 | 33.6 | 65.8 | 36.8 |
| Canon EF-S 18-135mm f/3.5-5.6 IS USM Compare | 86.9 | 75.2 | 53.1 | 42.4 | 82.3 | 77 | 30 | 95.8 | 77.8 | 93.4 |
Price
Value & Pricing
From £128
