The simpler media website CMS
I was looking into Zen Photo and having searched the topics on this cannot find a solution, I'm a portrait photographer so I hardly use "landscape" orientation. What I need to be able to do is display a full image (non-cropped) for all thumbnails and opening pages that use the "larger" thumbnail like Bootstrap. (looked at thumb size but grayed out, set "crop thumbnails to zero, made no difference). I did see another post where "maxspace" was mentioned, but the URL to the documentation page has gone missing, and I can find no setting. Here's a couple of screenshots of what I need to resolve.
It depends of the theme if it supports uncropped thumbnails. Those greyed out options mean your current theme does not. Reason is that using uncropped images is not as easy to realize with a layout by CSS (at least when the official already marked as deprecated themes were made) and cropped thumbs being equal look "cleaner".
The only chance then is to modify the theme used. For the basics we have a tutorial: