different resolution when dragging a card

I just created a deck card inside a map window and I added just one card to then drag it on board map. The deck shows the hidden card, but when I drag it to the board it shows the playable face of the card. The basic piece image used has the same resolution of the mask one, but after drag it on the board, the playable face it seems to be smallest. Any idea of would could happen? I’m very beginner designing a module. thanks.