I want to upgrade my Canon DSLR to either an 80D or 77D. The only thing that I find really lacking in the 77D is AFMA, but there is free Magic Lantern software. Can I safely assume, in practical terms, if I ever need to calibrate any lens on a 77D, it's just a matter of installing Magic Lantern?
Can I safely assume that in practical terms if I ever need to calibrate any lens it's just a matter of installing Magic Lantern?
No. There is no stable version of Magic Lantern currently available for the EOS 77D. There is neither a "Main Build" nor a "Port in Progress" for the 77D. If or when one will be available is anyone's guess.
Each camera model requires its own version of ML. Sometimes even different firmware versions of the same camera model requires slightly different versions of ML, or there is a version available for a previous firmware version but not the latest firmware version of a specific camera.
No. Not only has porting only just begun for the 77D or 80D (i.e., they're still a ways away from having released versions of Magic Lantern that will work for them) Magic Lantern cannot intercept or affect the lens/camera communication, and as autofocus microadjustment (AFMA) settings are custom functions, and therefore are differently defined for every camera body model, (AFMA) cannot be added to any Canon camera via Magic Lantern.