I am trying to have a background image that will fill the whole page. But it keeps cropping parts. Even if I make the image tiny in the centre of a large whitespace. What dimensions would you reccomend to get the least ammount of cropping?
I don't think there's a right answer here. Backstretch keeps your image in the right aspect ratio and since it's a background image that fits the whole page it really depends on the screen of the person viewing the image.
Using an image as a full-screen background image and keeping the correct aspect-ratio will result in cropping (when using backstretch).