If I already owned a 50-135, I would probably not swap it out for a 75-150/E (I speak as an owner of the latter, but I have tried out the former). The primary disadvantage of the 50-135 is the 62mm filter size, the slightly shorter max. focal length, and it's more-or-less token macro mode, but the two lenses are otherwise quit comparable. The build quality of the 50-135 is of course higher, but the 75-150/E isn't so bad (main problems are the plastic aperature ring and the zoom action tending to go quite loose over time). In sharpness terms, one senior Nikon technician was quoted as saying that these two lenses were the sharpest Nikon zooms ever made (pre-AF). The hood for the 75-150/E is the HN-21, and it is long out of production, and tends to be hard to track down, as few of the mass-market purchasers of series E lenses worried about subtelties like hoods. The suggestions of the HS-7 or HR-2 are both good and I have tried them both before I found a new HN-21 in stock at a NY camera dealer. As was mentioned by others, it's a _really_ good idea to use a hood at all times with a 12-element zoom lens, if only to increase contrast in your photos, and secondarily, to protect the lens from damage. grant..
