Basement Humidifier

I live in Wisconsin and just built a rec room and would like to put some prints down there. I'm considering 2 options Canvas or Metal prints due to the damp conditions. It's not overly damp but it's still a basement.

I don't really have any concerns with the metal format but I'm wondering what others have experience with canvas in this in environment. My main concern is that I could get some warping of the print due to the wood frame?

Any input is appreciated. Would a Basement Dehumidifier help? Is that one that I posted the correct kind to look into? Thanks, Al