News Canon has made an RF speed booster! However, there's catch…

Makes sense to only have the adapter work on the C70 because of the sensor size difference between it and a Full Frame mirrorless camera. Plus it mounts to the C70 so you can pick one up and attach your EF lenses and go. It's a great option for current "C" users if they're looking to upgrade. Used C200's are still $5,000 on eBay, the C70, with the mount, would only be $1,000 more for the newest tech and a third of the price of the 1D C when it released 8 years ago.
 

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