Moving to a mirrorless camera usually means facing an adapter decision before you can use the lenses you already own. The four adapters here cover four different mount pairings, and the listed price to consider changes with the pairing. The right one depends on the lens mount on your glass and the camera mount on your body.
Quick Take
The choices split by mount pairing more than by price. The K&F CONCEPT M42-L is aimed at L-mount cameras with M42 screw lenses. The K&F CONCEPT A-to-E adapter targets Sony E-mount bodies that still use Minolta AF or Sony A glass. The EF-EOS R adapter is the one in this group with autofocus, image stabilization, EXIF data, and electronic aperture support. The B4-NEX ring is the specialized pick for B4 2/3-inch lenses on Sony E-mount bodies.
Listed Price Comparison
| Product | Mount Pairing | Listed Price | Price Bar |
|---|---|---|---|
| K&F CONCEPT Lens Mount Adapter M42-L | M42 screw lens to L-mount camera | USD 29.99 | |
| Lens Mount Adapter Ring B4-NEX | B4 2/3-inch lens to Sony NEX E-mount | USD 58.99 | |
| K&F CONCEPT Lens Adapter for Sony Alpha Minolta AF | Minolta AF or Sony A lens to NEX E-mount | USD 24.49 | |
| EF-EOS R Len Mount Adapter Accessory | Canon EF/EF-S lens to EOS R RF mount | USD 28.49 |
Decision Matrix
| Adapter | Lens to Camera Route | Control | Use Case |
|---|---|---|---|
| K&F CONCEPT M42-L | M42 screw lens to Leica/Panasonic L-mount | Manual focus, infinity focus allowed | L-mount bodies with vintage M42 glass |
| B4-NEX Adapter Ring | B4 2/3-inch lens to Sony E-mount | Manual diaphragm control | Sony E bodies with B4 broadcast or industrial lenses |
| K&F CONCEPT A-to-E | Minolta AF or Sony A lens to Sony E-mount | Manual focus, infinity focus allowed | Sony E bodies with older A-mount or Minolta AF glass |
| EF-EOS R Adapter | Canon EF/EF-S lens to EOS R RF mount | Autofocus, IS, EXIF, electronic aperture support | Canon EOS R bodies with EF/EF-S lenses |
Product Notes
K&F CONCEPT Lens Mount Adapter M42-L Manual Focus For M42 Lens to L Mount Camera
This adapter is aimed squarely at L-mount cameras and M42 screw-mount lenses. It works with Leica SL, SL2, T, TL, TL2, and CL plus Panasonic Lumix S5, S1, and S1R. The construction is brass and aluminum, and the adapter is manually operated with infinity focus allowed. That manual operation is the trade-off: M42 lenses will keep their manual-focus workflow, and you won't get AF help from the camera. For vintage M42 glass on an L body, it's a direct match.
Lens Mount Adapter Ring B4-NEX for B4 Lens to Sony NEX E-mount Camera
This is the B4 specialist in the set. It mounts B4 2/3-inch lenses to Sony E-mount bodies, with compatible bodies including NEX-3, NEX-5, NEX-6, NEX-7, α6300, α6500, and several E-mount camcorders. The adapter ring is brass and aluminum, and diaphragm control is set manually on the lens, so aperture handling stays on the lens rather than the camera. If you have B4 broadcast or industrial lenses, this is the route to keep using them on a Sony E body; just plan to manage the diaphragm by hand.
K&F CONCEPT Lens Adapter for Sony Alpha Minolta AF A-Type Lens to NEX E-Mount
This adapter bridges Minolta AF and Sony A-mount lenses to Sony E-mount bodies. Compatible cameras include NEX-3, NEX-5, NEX-6, NEX-7, a7-series, a9, a3000, a5000, a5100, and a6000-series. It is manually operated and allows infinity focus, with a brass-and-aluminum build. The camera needs to be set to function without an E-mount lens attached, so that setting is part of the setup. If you have older A-mount glass on a Sony E body, this adapter is the straightforward fit, but you'll focus manually.
EF-EOS R Len Mount Adapter Accessory For Canon EF EF-S Lens To EOS R RF Mount
This third-party adapter is built for Canon EF and EF-S lenses on EOS R and RF-mount bodies. It supports autofocus, lens image stabilization, complete EXIF data transmission, and electronic aperture control, which separate it from the manual adapters in this group. It uses an aluminum alloy body and gold-plated contacts, and the fastening is snap-on, so the lens ring clips into place. The limitation is that it's third-party hardware, not a Canon-branded part, and its compatible model is 'For Canon EF EOSR.'
Final Recommendation by Use Case
- L-mount body with M42 screw lenses: K&F CONCEPT Lens Mount Adapter M42-L Manual Focus
- Sony E-mount body with Minolta AF or Sony A lenses: K&F CONCEPT Lens Adapter for Sony Alpha Minolta AF A-Type Lens to NEX E-Mount
- Canon EOS R body with EF/EF-S lenses: EF-EOS R Len Mount Adapter Accessory For Canon EF EF-S Lens To EOS R RF Mount
- Sony E-mount body with B4 2/3-inch lenses: Lens Mount Adapter Ring B4-NEX for B4 Lens to Sony NEX E-mount Camera
