That’s assuming you can find some way of doing that conversion. The ideal way would be to grow plants, but you’d either have to breed them to withstand the near-vacuum of Mars’s atmosphere, or find some way of bringing the CO2 into your pressurised living space. Given the huge pressure differential, that’d be difficult.
Are you sure? There doesn’t seem to be any way to overlay a secondary offset image to aid in focusing. The prism in the viewfinder is only being used to show digital information.