Thx, I tried it and it seems to work with a lot more pictures. I guess it has to do with the treshold how many images are loaded outside the viewport.
Are there plans to integrate something like the RICG plugin does
Sure, here is the link: http://wordpress.sineos.de/ haven't found anything which looks like lazy loading and also looking at the net console, all images have been loaded all time. Attached you find the BE screen. Have I done something wrong?