After debuting them in February, Canon has launched its Extender RF 1.4x and Extender RF 2x teleconverters for the EOS R family of cameras. However, their reception has been somewhat dampened by their compromised compatibility with current RF lenses.
Teleconverters are a great way to shoot at longer focal lengths, by extending the reach of your existing telephoto lenses, without the extra cost of investing in a whole new lens. This is especially useful with a young ecosystem like Canon’s full-frame mirrorless lineup.
These two new Extenders are compatible with three RF optics; unfortunately, however, none of them is the Canon RF 70-200mm f/2.8 IS USM, which is a lens that many photographers would want to use with a teleconverter with.
The only lenses that are compatible with the Extenders are the trio of super telephotos that have just been announced: the Canon RF 600mm f/11 IS STM and Canon RF 800mm f/11 IS STM and Canon RF 100-500mm f/4.5-7/1 L IS USM.
Again, however, there are compatibility caveats. Such is the physical construction of the latter lens that both teleconverters can only be used at focal lengths between 300-500mm. While the adapters are smaller than their EF counterparts, the interior parts protrude and prevent them working below 300mm.
The full compatibility and focal length / aperture conversion is as follows:
|RF lens||with Extender RF 1.4x||with Extender RF 2x|
|Canon RF 600mm f/11 IS STM||840mm f/16||1,200mm f/22|
|Canon RF 800mm f/11 IS STM||1,120mm f/16||1,600mm f/22|
|Canon RF 100-500mm f/4.5-7/1 L IS USM||420-700mm f/8-10||600-1,000mm f/11-14|
|Canon RF 70-200mm f/2.8 IS USM||Not compatible||Not compatible|
|Canon RF 28-70mm F2 L USM||Not compatible||Not compatible|
While it’s obviously disappointing that the 70-200mm won’t work at all with the teleconverters, and the 100-500mm only half works, both the 600mm and 800mm primes are fully compatible – and the prospect of a 1,600mm focal length on an R-system camera remains incredibly exciting.
Scheduled to go on sale from the end of July, the Extender RF 1.4x will cost $499.99/ £559 (AU$1,010) while the Extender RF 2x will carry a $599.99 / £699 (AU$1,263) price tag.