how come facebook/blogspot cover photos/banners stretch after posting?

[Deana]

I have made several banners for blogspot and a few cover photos for facebook and they always look so nice and crisp when i make them in photoshop but as soon as i upload them they always strech a little, vertically it looks like, making it a little blurrier and not as sharp. the dimensions are fine, it is wide enough and big enough so it is within guidelines but it always does this.

take this link for example, if you look at the cover photo and click it to see the full image, you will see how crisp and sharp it looks, but by itself just visiting the page first..its blurrier and stretched. when you first visit and see it its stretched and blurrier, but when you click the cover photo and blow it up to see the whole thing, its so sharp, blogspot does that to. here the link:

http://www.facebook.com/pages/Mlb-is-lif...9672812963

WHAT CAN I DO TO FIX THIS? i spend so much effort making these and im upset they dont show off well......

Thanks!!!

[Andrew]

If you make them, make sure they're big enough to not stretch and distort, but make sure they're small enough so they will fit inside the crop rectangle. (What I call the crop rectangle is, is the main part of the picture to be shown on the page without clicking the picture / banner.)