Canon Extension Tube EF 12 II
The Canon EF12 II Extension Tube is a simple accessory that moves the lens optics further away, thus increasing the magnification of the lens. It has electrical connectors so that communication between lens and camera is maintained, but no optical elements of its own
The Canon EF12 II and EF25 II Extension Tubes are not compatible with EF-M or RF lenses, which are based on different mounts, but can be used with most EF lenses (see below for the exceptions) and with EF-S lenses. (Note that it's the lens that matters, not the camera. To be clear, you can still use these extension tubes if you're using a compatible EF or EF-S lens on an EOS R System camera with an EF-EOS R Mount Adapter or on an EOS M camera with an EF-EOS M Mount Adapter.)
Their predecessors, the Canon EF12 and EF25 Extension Tubes, were part of the EOS system from 1991 to September 2004, when Canon introduced the EF-S mount, designed for cameras with smaller, APS-C sensors. If you happen to get hold of them, these original EF extension tubes cannot be used with EF-S lenses, but since they have no optical elements they will work with the same EF lenses as the Mark II tubes.
The Canon EF12 II and EF25 II Extension Tubes are not compatible with the following lenses:
• EF 15mm f/2.8 Fisheye (now discontinued)
• EF 8-15mm f/4L Fisheye USM
• EF 14mm f/2.8L II USM
• MP-E 65mm f/2.8 1-5x Macro
• TS-E 17mm f/4L
In addition, the EF25 II tube is not compatible with the following lenses:
• EF 20mm f/2.8 USM
• EF 24mm f/1.4L USM (now discontinued)
• EF 24mm f/1.4L II USM
• TS-E 45mm f/2.8 (now discontinued)
• EF 11-24mm f/4L USM
There are also some limitations to using the EF12 II and EF25 II Extension Tubes with the following lenses – notably, they can't be used at the wide angle setting:
• EF 16-35mm f/2.8L III USM
• EF 24-105mm f/4L IS II USM
• EF 200-400mm f/4L IS USM Extender 1.4x
• EF-S 10-18mm f/4.5-5.6 IS STM
• EF-S 10-22mm f/3.5-4.5 USM
• EF-S 15-85mm f/3.5-5.6 IS USM
• EF-S 17-55mm f/2.8 IS USM
In addition, there are slight exposure problems with some combinations of cameras and lenses. The instruction leaflet provided with the extension tubes gives some guidance on this, but the best advice is to shoot some test frames with the camera and lens you intend to use and make a note of any exposure compensation that may be required. Keep this information safe for future reference.
CANON EXTENSION TUBE EF 12 II
The Canon EF12 II Extension Tube is a simple accessory that moves the lens optics further away, thus increasing the magnification of the lens. It has electrical connectors so that communication between lens and camera is maintained, but no optical elements of its own
The Canon EF12 II and EF25 II Extension Tubes are not compatible with EF-M or RF lenses, which are based on different mounts, but can be used with most EF lenses (see below for the exceptions) and with EF-S lenses. (Note that it's the lens that matters, not the camera. To be clear, you can still use these extension tubes if you're using a compatible EF or EF-S lens on an EOS R System camera with an EF-EOS R Mount Adapter or on an EOS M camera with an EF-EOS M Mount Adapter.)
Their predecessors, the Canon EF12 and EF25 Extension Tubes, were part of the EOS system from 1991 to September 2004, when Canon introduced the EF-S mount, designed for cameras with smaller, APS-C sensors. If you happen to get hold of them, these original EF extension tubes cannot be used with EF-S lenses, but since they have no optical elements they will work with the same EF lenses as the Mark II tubes.
The Canon EF12 II and EF25 II Extension Tubes are not compatible with the following lenses:
• EF 15mm f/2.8 Fisheye (now discontinued)
• EF 8-15mm f/4L Fisheye USM
• EF 14mm f/2.8L II USM
• MP-E 65mm f/2.8 1-5x Macro
• TS-E 17mm f/4L
In addition, the EF25 II tube is not compatible with the following lenses:
• EF 20mm f/2.8 USM
• EF 24mm f/1.4L USM (now discontinued)
• EF 24mm f/1.4L II USM
• TS-E 45mm f/2.8 (now discontinued)
• EF 11-24mm f/4L USM
There are also some limitations to using the EF12 II and EF25 II Extension Tubes with the following lenses – notably, they can't be used at the wide angle setting:
• EF 16-35mm f/2.8L III USM
• EF 24-105mm f/4L IS II USM
• EF 200-400mm f/4L IS USM Extender 1.4x
• EF-S 10-18mm f/4.5-5.6 IS STM
• EF-S 10-22mm f/3.5-4.5 USM
• EF-S 15-85mm f/3.5-5.6 IS USM
• EF-S 17-55mm f/2.8 IS USM
In addition, there are slight exposure problems with some combinations of cameras and lenses. The instruction leaflet provided with the extension tubes gives some guidance on this, but the best advice is to shoot some test frames with the camera and lens you intend to use and make a note of any exposure compensation that may be required. Keep this information safe for future reference.