Switching from the canon EOS 77D to the canon r6 mark II

[swosin]

Been using the 77D for a while and been thinking of switching over to the Canon R6 Mark II. I already have several lenses for the 77D with the EF mount.

I need to use my EF lenses with the new camera. The Canon EF-EOS R Mount Adapter should work right?

And if I use an adapter will I have any drawbacks like loosing autofocus functionality?

[Tronhard]

Hi and welcome to the forum:
Can you please advise exactly what lenses you are using with your 77D?  Especially if they are EF or EF-S lenses?

[Tronhard]

While I am waiting for your response, perhaps I can explain the context for my question...

The fact that you currently have a EOS 77D, which is an APS-C crop sensor camera, brings with it the possibility that you are using EF-S lenses that are designed specifically for a crop sensor.  While Canon EF and EF-S lenses will physically fit on the RF mount of the full-frame R6MkII, via the EF-Rf adapter, there is a potential issue. 

In the DSLR world, EF-S lenses would not physically fit into a FF camera body, because the rear of the lenses projected closer to the sensor, and foul the mirror.  This was because the sensor was smaller and therefore the lens could project further into the body and thus the sensor closer to the centre of focus, making lens design simpler, cheaper, and allowing for smaller bodies and lenses.

While the EF-S lenses will physically fit a R-series full-frame body, via the adapter, the image projected onto the sensor is still limited to that for a crop sensor camera, meaning that it will not use the available FF sensor area and will result in a loss of MP count - and this is quite significant.   

When relating the size of the two sensors, the dimensions for length and width of the FF sensor are each 1.6x larger than those of the APS-C sensor, thus when considering the areas of the two, that number is squared to a value of 2.56.  This means that the area recording the image projected by the EF-S lens is reduced by a factor of 2.56. So, as the maximum resolution of the R6MkII is 6000x4000, an EF-S lens will project to record only 3744x2496 of the available area on the FF sensor, or to put it another way: the R6MkII has a sensor capacity of 24MP, putting an EF-S lens will only record about 9.3MP worth of data.  This is referred to in the R6MkII Advanced User Guide on P1051.

 Here is a link to that guide: c012.pdf (start.canon)

Thus, there should be no compatibility issues with Canon EF lenses, but EF-S lenses are problematic.
As regards any third-party EF lenses you may have, Canon offers no guarantees that they will work with the R-series bodies.

I hope this is helpful to clarify the situation.

Thus

[ebiggs1]

"The Canon EF-EOS R Mount Adapter should work right?" "I need to use my EF lenses with the new camera"

To cut through the fog, yes, it will work. How well it works on EF-S lenses is varied but you stated you had some EF lenses. It should work well for them.