# item.guide
Side-by-Side Comparison Lens Mounts

Canon RF vs. Nikon Z

Comparing 2 standards across 9 specifications. 9 key differences identified.

Comparing:
Canon RF
Nikon Z

The Canon RF Mount (introduced in 2018 for the EOS R system) is a 3-tab full-frame mirrorless bayonet mount featuring a 20.0 mm Flange Focal Distance, a wide 54.0 mm inner throat diameter, and an advanced 12-pin high-speed data bus. Retaining the large 54mm diameter of the classical EF mount, it enables ultra-fast aperture lenses such as the RF 28-70mm f/2L and 50mm f/1.2L.

View full Canon RF spec sheet →

The Nikon Z Mount (introduced in 2018 for the Z-series mirrorless system) features the shortest Flange Focal Distance (16.0 mm) and the widest inner throat diameter (55.0 mm) among current major full-frame mirrorless mounts (Sony E, Canon RF, Leica L). This geometry enables extreme optical designs, including the ultra-fast NIKKOR Z 58mm f/0.95 S Noct.

View full Nikon Z spec sheet →

Specification Comparison Table

9 Parameters
Parameter / Spec
Flange Focal Distance (FFD)
20.00 mm (0.787 in) 16.00 mm (0.630 in — the shortest FFD among current major full-frame mirrorless mounts)
Inner Throat Diameter
54.00 mm (2.126 in — identical to legacy Canon EF mount) 55.00 mm (2.165 in — the largest throat diameter among current major full-frame mirrorless mounts)
Bayonet Tabs
3 asymmetrical stainless steel bayonet tabs with clockwise mounting twist 4 asymmetrical locking tabs with counter-clockwise twist (traditional Nikon direction)
Electronic Interface
12 contact pins (high-bandwidth bidirectional bus for lens control ring and Coordinated IS up to 8 stops) 11 gold-plated contact pins
Camera Systems
Canon EOS R5 / R6 / R3 / R8 / R, Cinema EOS C70 / C80 / C400, APS-C EOS R7 / R10 Nikon Z9, Z8, Z7 II, Z6 III, Zf (full frame), Z50, Zfc, Z30 (DX APS-C)
Legacy Adaptability
100% native AF/IS compatibility with all Canon EF/EF-S lenses via Canon EF-EOS R adapter (24mm spacer)
Lens Control Ring
Physical programmable control ring on all native RF lenses (aperture, ISO, exposure compensation)
Max Theoretical Aperture
Mount geometry (throat diameter and FFD) permits faster designs than F-mount allowed; the fastest lens actually shipped is the Z 58mm f/0.95 S Noct -- claims of a precise theoretical f/0.58 limit are back-of-envelope extrapolations, not a published Nikon figure
Legacy F-Mount Adaptability
Nikon FTZ / FTZ II adapter (30.5 mm spacer) provides full AF/AE with AF-S and AF-P NIKKOR lenses