TV mirroring of photos on sony Alpha A7III - is not covered the whole screen by the mirrored photo

[Vandraattila]

I recently bought a Sony Alpha A7III. When I have tried to mirror the photos on the TV (109 cm diagonal, HD LG smart TV), the photo size was approximately the same as my additional laptop BENQ monitor (59 cm diagonal). 3/4 of the screen was empty. I searched in help of the camera, but I have not found any information about a setting related to this phenomenon. The photo is RAW type (ARW extension). . Can you help me? 

[Vandraattila]

the phopto is 6000*4000 px, 50.8*33.87cm size

[Vandraattila]

I think that is the size of the picture with 300dpi ... OK, but question remains, can I mirror the image on the whole TVscreen? From my computer I can.... From the camera is not possible?