I'm trying to create a custom open graph story to Facebook but I'm having some trouble getting the og:image to show properly. I'm using a 1200*630 sized image as recommended here and here but on my timeline it gets cropped in to a square from the left edge of the image. It also shows as a square in the story preview though this time it's cropped from the center.
How can I get the image to show in the correct aspect ratio and size? Is it just the test environment to blame or do I need to add something on my server side? I've already tried to use the meta tags width and height with no success.
Currently the tag looks like this:
<meta property="og:image" content="http://www.linktomyimage/1200x630pixels.png" />