it could be anything.
a trick i learned with my camera -- if you focus on something before taking the picture, you can force the focus. when i try and take pics my camera doesn't know what to focus on -- the plant, the background, and it comes out blurry.
i point it at something to focus on, the same distance away as the distance from the bud to the camera, then when it focuses, i keep the button slightly pressed, then go back and take a picture of the bud.
viola, crisp and clear pics.