Handy Lightbox large images looked squashed

I’m using handy Lightbox Version 1.4.5
It’s wonderful and brilliant to use, but all the large images are squashed and have a white blank area to their right. You’ll see what I mean here and click in the Angela image, the top one with the bride

https://chriss-wedding-cars.co.uk/wp/our-cars/

Theme: Attitude Pro
Version: 1.3
By Theme Horse

Any help and advice very gratefully received. Thank you.
Ted

https://www.ads-software.com/plugins/wp-handy-lightbox/