It should be said that it is quite big. If nothing else, a7m2 can't shoot 4k. This is not a good question, but a7m2, as an old machine of 20 14, doesn't support this at all.

Of course, in fact, the video shooting ability of a7m3 is average. Shouldn't your wedding camera give priority to Panasonic? Now, some of them have switched to Fuji xt3. Sony used to use S-series machines, but the S-series has not been updated in the past two years. Of course, the requirements for video quality are not so strict, and some insist on using Canon.