Now we see through a glass, darkly...
- Apr 5, 2016
The more comments I see about the new RF extenders, the more confused I get.
if, as some say, the RF 70-200mm isn't compatible due to the lens elements being too close to the mount leaving no room for the extender, will this not effect most of the RF glass range as the whole point of the RF mount is to reduce distance between the sensor, flange and 1st element??
Are the RF extenders therefore going to be like the RF drop in filter mounts, where they can only be used with EF glass?
If so, this is pretty poor for anyone with native RF lenses. I suppose all will be revealed on 09/07/20.
Canon has never made wide angle or even normal lenses compatible with extenders. For prime lenses, nothing shorter than 135mm can handle an extender. For zoom lenses, the EF 70-200 series and the EF 100-400 series allow extenders, but that is based on the assumption that users will be at the longer ends of the focal length range when extenders are attached.
The big benefit of having a shorter registration distance is for wider angle lenses. Normal lenses benefit some, but not as much as wide angle lenses do. 70mm is right on the line between normal and telephoto. Anything past 85-100mm is not going to see much benefit from shorter registration distances in terms of image quality. A lens in that focal length range might see a benefit in terms of overall size and weight.