Andre, is there somewhere in the tutorial that goes through the header setup process? I am real confused as to the recommended size. At first I assumed that because there was an option fo crop and publish, that would be what I should do. However, doing that really cuts into the image. If cropping the image takes it to the recommended size, shouldn’t we size it that way to begin with? Otherwise, why is it even in there as an option?
I generally recommend to people to crop and size their own images before uploading because doing that first gives a lot more flexibility for a final image. I’m assuming you are referring to the WP Header feature? When you upload an image, it’s important to make sure it’s equal or larger than the size being used. When you upload it, the feature has it’s own cropping tool that you can move around the image to crop it, otherwise, I still say it’s better to prepare the images before you upload them.
Please note when using the cropping tool in the WP Header or even when you upload an image for a page or post, if your image is smaller than needed, WordPress does not make it bigger to fit.