Helps to reduce stray light which can cause flare.
Use of specifically engineered Nikon lens hoods is highly recommended.
In less-than-ideal lighting conditions, the performance difference can be substantial.
Flower-Type bayonet lens hood provided with select NIKKOR lenses.
By reducing the amount of non-essential light falling onto the front lens element, lenses can better achieve their optimum optical performance, producing more saturated images.
HB-50 Bayonet Lens Hood 8 8
Just pitiful! I've had many Nikon products over the years and few have disappointed me as much as this hood. It's inconceivable to me that Nikon would couple this hood with a $1K lens....just doesn't make sense. Nothing to add from what's been said here and other sites: the fit is sloppy and can easily fall off. Nikon should pony up and fix this by providing a better solution for people who have bought this lens. At this point I'll try a 3rd party hood as soon as it's offered. Can't believe I'm saying that...... "getting a 3rd party hood for my Nikon lens"? February 17, 2011
Easily fall off I couldn't remember how many times the hood fell off after I got the camera out of the bag, and as expected, I lost it. I didn't know how much it cost until I tried to replace it. It is way overprice for a piece of plastic. Googled it and the cheapest price was $35. Way to go Nikon. February 6, 2011
Broke before I could use it I put my brand new lens and hood in my camera bag. My bag got compressed a little and the hood snapped in half. I own other Nikon lenses and their hoods are still going strong after years of use and sometimes abuse. This hood is too flimsy. March 24, 2012