More sensor talk: Maybe a 32.5MP APS-C sensor is coming now

In this latest rumor, now we have the possibility that Canon will release a 32.5MP APS-C sensor for the upcoming M5 Mark II and the mid level DSLR camera body.

Supposedly this source is 100% certain that this is going to come.

While I'm not entirely sure about this, it's certainly probable from the scaling point of view:

A 32.5MP APS- C sensor is an 84MP full frame sensor. Canon has scaled up to 250MP for APS-H and even in the past committed that a 120MP DSLR was in development.
A 32.5MP APS-C sensor scales down to 11.5MP for a 1" sensor, and Canon currently produces 9MP 1" sensors, not a significant stretch, and even less if rumors are true that Canon is releasing a G7X Mark III with Canon's own 20MP 1" sensor in it.

If we look at the Canon EOS API source code though, we see that the two new PowerShot ILC's (which are EOS-M class cameras) are calculated out as 24.1MP cameras. It could be that is dummy data in there, and that Canon will update EOS utility at a later date for the M5 Mark II.

One problem I have with this though is the design rules needed.

A 32.5MP camera would be approximately 6982x4655 image resolution with a 3.2um pixel pitch. Cut in half for dual pixel auto focus, would mean that each half-pixel (part of the pair of half pixels that make up a full pixel for dual pixel autofocus) would be approximately 1.59um in size. Canon's current sensor fabrication technology is around .18um, this would seem not fine enough.

Canon has used course design rules in the past. For example, the 18MP sensor in the 60D and below cameras, used .5um for a 4.29um pixel size, however, that was not a dual pixel auto focus sensor which adds to the inefficiency. They also aren't very good sensors with respects to current camera sensors. It's a complete theory from me, however, I do believe the pause in Canon's sensor development and sticking with the 18MP sensor was because the old equipment was not good enough for the new Dual Pixel auto focus sensors. Canon most likely upgraded fabrication lines to 180nm to support Dual Pixel autofocus. We do know for certain that the 80D was fabricated with 180nm technology and that 60D was fabricated with 500nm.

We do know that Canon has at least some facilities with smaller design rules (at least down to 130nm or .13um). It could be that this new sensor is also using new fabrication equipment that Canon has quietly upgraded. It's should be pointed out that to support the 20MP 1" sensors, Canon would have had to upgrade their fabrication anyways.

Then we have the processors.

We know that currently, DIGIC 8's maximum throughput seems to be around 240 mega pixels per second (EOS R does 30MP at 8FPS, and the M50 does 10FPS at 24MP)

If Canon released a 32.5MP M5 Mark II, then the max frames per second (fps) performance would be around 7fps. While megapixels sell cameras, fps does as well, it would seem odd that Canon would release a camera that was remarkably slower than it's predecessor (the M5 reaches 9 fps). A more conservative 26MP would see the M5 Mark II reach 9fps, the same as it's predecessor, and still achieve a higher MP rating than other Canon cameras. Canon in the past seems to have balanced megapixels and fps specifications over consecutive releases. Even the 60D to 70D which featured a jump from 18 to 24MP, also saw a jump in fps from 5.3 to 7 fps.

So I'm not so sure about this rumor, granted CanonRumors listed it as a CR1, but I'm not entirely sure it is likely after delving into it in depth. It's certainly doable for Canon. They do have the technology, it's a matter of whether or not it makes sense for Canon to make this huge jump in mega pixels.

Time will tell