The simpler media website CMS
First of all, I'd like to thank the authors for a great application I have been using since 2009.
My initial installation was ZP 1.2.5. The gallery was abandoned in 2015, but I want to start over now.
Here is a static copy of the old gallery for reference: http://leitseite.net/photo/galleries/index.html
As you can see, the thumbnails (and all images inside) are uncropped, have constant image height and variable image width. On the second page, there is a Panorama gallery with a custom cropped image.
I found this not to be (easily) possible with recent ZP versions, here is my attempt: http://leitseite.net/photo/galleries.new
The main index size is enlarged from 650px to 1170px in the CSS (was too small then, and is much too small now for modern screens).
Standard image size is 1170x780.
The first index page is already like a clone, however I had to use the custom functions to get there:
There is a similar problem in case of the thumbnails: you cannot get uncropped constant height even in principle, in spite of the recommendations I found here in the forum.
The standard aspect ratio is square. Using the crop option does not help because it crops all images equally (a 3:2 shot will look even wider).
I am now stuck on my Panorama gallery on the second page (http://leitseite.net/photo/galleries.new/page/2/) because I cannot custom crop the wide images to a fitting thumbnail (had to use custom functions because of the above), and the wide thumbnail image destroys the layout of the index page. I would have to delve in and find out how I can define something different for that single gallery.
This could all be easily fixed if a constant height with preserved aspect ratio would be offered, which I think is also the way it makes most sense because it never messes with the layout. Film contact sheets were also produced this way.
Ironically, that was just the way the old Zenphoto up to 1.3 was working, as you can see from the static copy. The panorama thumbnail is a custom crop and the rest was just defined in the theme options.