Understanding Camera Mounts:
Sony, Canon, Nikon & Fujifilm Explained
Which lenses fit which cameras, and how adapters let you use old glass on new bodies.
You've decided to buy a mirrorless camera. You choose a Sony body, then discover the Canon lens you borrowed from a friend won't fit. Or you switch from a Nikon DSLR to a Nikon Z mirrorless and wonder if your old lenses are now useless. Camera mounts are the reason. Understanding them before you buy saves you hundreds of pounds and months of frustration.
This guide explains every major camera mount system sold at Carlos.gi, Sony E-mount, Canon RF, Nikon Z, and Fujifilm X, in plain English. We'll cover what makes each system different, which lenses are compatible, and how mount adapters let you use older glass on newer bodies.
By the Carlos.gi team - Gibraltar's specialist camera retailer. Covers: what a camera mount is, the 4 main mirrorless systems, legacy lens adapters, a full compatibility chart, and three adapters available at Carlos.gi.
What Is a Camera Mount?
The physical and electronic connection between your camera body and lens
A camera mount is the circular interface where a lens attaches to a camera body. It is both a physical connection (the bayonet ring that locks the lens in place) and an electronic connection (the metal contacts that pass autofocus, image stabilisation, and aperture data between the lens and camera).
Each camera manufacturer designs their own mount. This means a Canon lens will not fit a Sony body, and a Nikon lens will not fit a Fujifilm body, without an adapter. The mount also determines the flange distance (how far the lens sits from the sensor), which affects optical performance and adapter compatibility.
Mount Systems
Native Compatibility
at Carlos.gi
Lenses are brand-locked. A Sony E-mount lens only fits Sony E-mount cameras. A Canon RF lens only fits Canon RF cameras. The only exceptions are third-party lenses (Sigma, Tamron) which are made for specific mounts, and legacy lenses used with adapters.
The 4 Main Mirrorless Mounts
Sony E, Canon RF, Nikon Z, and Fujifilm X - what makes each different
Sony's E-mount is the most mature mirrorless system in the world, with the largest native lens ecosystem of any mirrorless brand. It covers both APS-C cameras (ZV-E10 II, A6700) and full-frame cameras (A7 series, A9 series) using the same mount, though APS-C lenses will crop on full-frame bodies.
Canon's RF mount was designed from scratch for mirrorless cameras and features a wide 54mm diameter, the largest of any mirrorless system. This allows Canon to design optically ambitious lenses. The RF mount also features a control ring on lenses for direct exposure adjustment. Canon EF lenses (from DSLRs) can be adapted using the EF-EOS R adapter with full autofocus.
Nikon's Z mount has the shortest flange distance of any mirrorless system (16mm) and a very wide 55mm diameter, giving Nikon's optical engineers maximum flexibility. The Z mount is used on both Nikon's APS-C cameras (Z30, Z fc, Z50) and full-frame bodies (Z6III, Z7II). Nikon F-mount lenses from DSLRs adapt via the FTZ II adapter with full autofocus support.
Fujifilm's X mount is an APS-C only system, there is no full-frame Fujifilm mirrorless. This focus on a single sensor size has allowed Fujifilm to build an exceptionally deep lens ecosystem for APS-C, with over 30 native XF lenses. The X mount also accepts Leica M-mount lenses via the Fujifilm M Mount Adapter, making it popular with photographers who own vintage Leica glass.
Using Adapters: Old Lenses on New Cameras
How to use your existing DSLR lenses on a new mirrorless body
A mount adapter is a ring that sits between a lens and a camera body, bridging two different mount systems. The best adapters, like those made by Canon, Nikon, and Fujifilm themselves, maintain full electronic communication, meaning autofocus, image stabilisation, and aperture control all work exactly as they would with a native lens.
Adapts all Canon EF and EF-S lenses to Canon RF cameras. Full autofocus, IS, and aperture control. The Control Ring version adds a physical dial for exposure adjustment.
Adapts Nikon F-mount DSLR lenses to Nikon Z cameras. Full autofocus on AF-S and AF-P lenses. Older AF and AI lenses work in manual focus mode only.
Adapts Leica M-mount lenses to Fujifilm X cameras. Manual focus only, no electronic contacts. Popular with photographers using vintage Leica, Voigtländer, or Zeiss M-mount glass.
You cannot adapt lenses across brands. A Canon EF lens cannot be adapted to a Sony E-mount camera with full autofocus. A Nikon F lens cannot be adapted to a Canon RF camera. Only same-brand legacy-to-modern adapters (EF→RF, F→Z) maintain full electronic function. Cross-brand adapters exist but typically lose autofocus entirely.
Mount Compatibility Chart
Which lenses work on which cameras - at a glance
| Lens Mount | Sony E | Canon RF | Nikon Z | Fujifilm X |
|---|---|---|---|---|
| Sony E-mount | ✓ Native | ✗ | ✗ | ✗ |
| Canon RF | ✗ | ✓ Native | ✗ | ✗ |
| Nikon Z | ✗ | ✗ | ✓ Native | ✗ |
| Fujifilm X | ✗ | ✗ | ✗ | ✓ Native |
| Canon EF (DSLR) | ✗ | ✓ via adapter full AF |
✗ | ✗ |
| Nikon F (DSLR) | ✗ | ✗ | ✓ via adapter AF-S/AF-P only |
✗ |
| Leica M | ✗ | ✗ | ✗ | ✓ via adapter manual focus |
| Sigma (Sony E) | ✓ Native | ✗ | ✗ | ✗ |
| Sigma (Canon RF) | ✗ | ✓ Native | ✗ | ✗ |
Nikon FTZ II Mount Adapter
The official adapter for using Nikon F-mount lenses on Z cameras
The Nikon FTZ II is the second-generation adapter for using Nikon F-mount DSLR lenses on Nikon Z mirrorless cameras. It supports full autofocus on AF-S and AF-P lenses, and manual focus on older AF and AI lenses. The FTZ II is 30% lighter than the original FTZ and removes the tripod mount, making it more compact for everyday use.
This adapter is essential if you're upgrading from a Nikon DSLR (D850, D780, D7500) to a Z-mount camera and want to keep using your existing F-mount lenses. Image quality, autofocus speed, and VR (vibration reduction) all work exactly as they would on a native DSLR body.
- Full autofocus on AF-S and AF-P lenses
- VR and aperture control maintained
- 30% lighter than original FTZ
- Official Nikon adapter - guaranteed compatibility
- No autofocus on older AF or AI lenses
- Adds 30mm to lens length
- No tripod mount (removed in FTZ II)
- Expensive for what is essentially a metal ring
Canon Mount Adapter EF-EOS R
The official adapter for using Canon EF lenses on RF cameras
The Canon Mount Adapter EF-EOS R allows you to use any Canon EF or EF-S lens on a Canon RF mirrorless camera with full autofocus, image stabilisation, and aperture control. It is dust and water-resistant to match Canon's L-series lenses, and adds minimal weight to your setup.
This adapter is ideal if you're upgrading from a Canon DSLR (5D Mark IV, 6D Mark II, 90D) to an RF-mount camera (EOS R6 Mark III, EOS R50) and want to keep using your existing EF glass. Canon also makes a Control Ring version of this adapter (£129) which adds a physical dial on the adapter itself for direct exposure control.
- Full autofocus on all EF and EF-S lenses
- IS and aperture control maintained
- Dust and water-resistant
- Control Ring version available (£179
- Adds 24mm to lens length
- EF-S lenses crop on full-frame RF bodies
- No tripod mount
- Expensive for a passive adapter
Fujifilm M Mount Adapter for X-Mount Cameras
Use Leica M-mount lenses on Fujifilm X cameras
The Fujifilm M Mount Adapter allows you to use Leica M-mount lenses, including vintage Leica, Voigtländer, and Zeiss ZM glass, on Fujifilm X-mount cameras. This is a fully mechanical adapter with no electronic contacts, so all lenses work in manual focus mode only. Fujifilm's focus peaking and magnification tools make manual focusing straightforward.
This adapter is popular with photographers who own vintage Leica rangefinder lenses and want to use them on a modern digital body. The Fujifilm X100VI and X-S20 are particularly well-suited to manual focus shooting, with excellent EVF magnification and focus peaking tools.
- Unlock vintage Leica M-mount lenses
- Fully mechanical - no electronics to fail
- Compact and lightweight
- Official Fujifilm adapter
- Manual focus only - no autofocus
- No aperture data transmitted to camera
- Requires manual exposure compensation
- Expensive for a mechanical adapter
Which Mount Should You Choose?
Picking a camera system based on your needs and existing gear
- You want the largest lens ecosystem
- You need Sigma or Tamron third-party lenses
- You shoot video and need Sony's autofocus
- You want a single mount for APS-C and full-frame
- You already own Canon EF lenses
- You want Canon's colour science
- You need the control ring on lenses
- You shoot portraits or weddings
- You already own Nikon F-mount lenses
- You want the widest mount diameter
- You shoot landscapes or wildlife
- You prefer Nikon's ergonomics
- You only need APS-C (no full-frame)
- You want film simulation modes in-camera
- You own vintage Leica M-mount lenses
- You prefer compact, retro-styled bodies
If you already own lenses, stick with your brand. The cost of switching systems (selling old lenses, buying new ones) almost always outweighs any technical advantage of a different mount. If you're starting fresh, Sony E-mount offers the most flexibility and the largest used lens market.
The Bottom Line
"Camera mounts are brand-locked by design. Choose your system based on the lenses you already own, or the lenses you want to use in five years."
Camera mounts are not interchangeable. A Sony lens will not fit a Canon camera. A Nikon lens will not fit a Fujifilm camera. This is intentional, each manufacturer designs their mount to optimise optical performance, autofocus speed, and lens size for their specific sensor and processor architecture.
If you already own lenses, the decision is simple: stick with your brand and use an adapter if you're upgrading from DSLR to mirrorless. If you're starting fresh, Sony E-mount offers the most flexibility, but Canon RF, Nikon Z, and Fujifilm X are all excellent systems with deep lens ecosystems.
| Mount System | Best For | Cameras at Carlos.gi |
|---|---|---|
| Sony E-mount | Video creators, largest lens ecosystem | ZV-E10 II · A6700 · ZV-1F |
| Canon RF | Portraits, weddings, Canon EF owners | EOS R50 · EOS R100 · EOS R6 Mark III |
| Nikon Z | Landscapes, wildlife, Nikon F owners | Z30 · Z fc · Z50 II · Z7II |
| Fujifilm X | APS-C only, film simulations, retro bodies | X100VI · X-S20 |
Need Help Choosing a Camera System?
Our team at Carlos.gi can help you choose the right mount system based on your existing gear, budget, and photography style. Visit us in Gibraltar or contact us online.
