Zstack with images having different sizes

hello squidpy team
Again many many thanks for your great package !
I am truing to create a Z stack object following this tuto:
but my images does not have the same size and I get the following error message:
cannot reindex or align along dimension ‘y’ because of conflicting dimension sizes:
shape=(15583, 16436) and shape=(15970, 16512)
do I need to fill the smallest image with 0 ?
Many Thanks