CanonWatch reports that it has heard from a new source that Canon is developing a high resolution version of the R5 called the R5S or R3S and a video-centric model called the R5C or the R3C. The high-res version would reportedly have about 80 megapixels, and the video model’s resolution would halve to about that of the R6, but add a few goodies, such as 2.8K supersampling in super35 mode and 4k/120 without cropping. Both would get new heat sinks.
The rumored specs for the high resolution strain theoretical limits, with 12 frames per second at 80 megapixels suggesting a throughput higher than anything Canon has yet put to market, more than doubling the pixels per second of the 1DX Mark III.
Among the reasons to be skeptical is the fact that all rumors emerging for multiple decades involving a camera using the 3 series have proven to be false.