We use a cropped image in the newsletter with the dimension of 636x358px with North crop. We don’t use this type of crop anywhere on the site. We use the same dimension with Center crop for the facebook share image (if the image is narrower than 700px), and we have some - I think legacy - codepath to crop video thumbnails behind the
stream_video_thumbnail feature switch. So I think we should abandon the 636px wide crops.
When we show an image in the stream on an embiggened post (that’s the closest thing we have on the site to the image in the newsletter) we crop to Center and crop to 1200x675px, but that would be too large for the newsletter. Luckily we already have a 800x450px transform, which would be perfect here.
We squash the image in the newsletter fit to a 540px wide container and since the ratio stays 16:9 the image will appear the same size as now. The only noticeable change will be the change in the crop gravity, but that now will be consistent with what we use in-stream.