Landscape & portrait image orientation together?

Hi Guys

I have a wordpress, woocommerce site selling fine art prints. I have been trying to display both landscape and portrait orientated thumbnails together but can never get them so that they look visually pleasing. I have tried hard cropping but tend to loose parts of each image. I have setup a sample category with both image thumbnails http://www.northernwild.co.uk/index.php/product-category/northumberland/ Can anyone help please?

cheers
John

It can be done with css but I do not know if Wordpress would like it.
I would extend the canvas so they are both the same size; a simple way of doing that is to use Imagemagick. It can be installed on a desktop and in windows I would create a batch file you can just drop the photo over and it can be resized if required and the extended canvas added. I used to use this method on my gallery.