I have just purchased a second hand Tamron 18-250mm lens, unfortunately it came without a lens hood. Now since I don't like taking photo's without a lens hood, can any one recommend a decent lens hood for this lens. I have read that the one that normally comes with this lens is a petal shaped hood, but this can some times will cast a shadow onto the lens. I have considered a 3 stage rubber lens hood, has anyone had any experience with this type of hood and basically are they any good? Or which lens hood would you recommend?