Centering Portrait Pics

Hi

I’m new to this plugin & WordPress so forgive me if this is a simple issue.

I’ve created a slideshow and uploaded a mixture of photographs in both landscape & portrait.

On my page I am using the code: %%wppa%% %%slideonlyf=1%% %%align=center%%

When viewing the photos, the photos taken in landscape mode are fine but the portrait ones display to the left of the page rather than in the middle of the screen.

Thanks

https://www.ads-software.com/extend/plugins/wp-photo-album-plus/