How To Increase Mirror IQ/Resolution

Is there anyway to increase the resolution of the mirrors? I don't need it super sharp, but it currently looks like a PC game from the 1980s. Is there a notepad file or something where I can type in the resolution used for the mirrors or something?

WHat about for draw distance of mirrors? I would like objects in the mirror to not disappear until they are further away than they currently are. Objects too close in the distance currently disappear.

Can anyone help? I'd appreciate help with both, but the resolution is my primary concern....