Customer Rating: 
Summary: Works great and gives a nice protection from sunlight
Comment: I got this hood for my new EF50mm and it is all I could ask for. It gives a nice look to the lens and camera and protects the lens from direct sunlight.
If you get the EF50mm this Lens Hood is a must have!!
LR
Customer Rating:
Summary: regret getting it
Comment: I think it's too pricey for what you're getting. This is a flimsy plastic hood with a metal ring adapter which screws onto the front of the lens. Canon probably gets both pieces manufactured for pennies. The two pieces awkwardly fit together and it's tricky to get the hood mounted onto the ring. So, 1 star for cool looks and 1 star for trying.
Customer Rating:
Summary: does it matter?
Comment: very awkward hood which by appearance is quite small. not sure if it acutally makes a difference and so far i've left it off the lens. not quick to get on and off.
Customer Rating:
Summary: POS, broke quickly, difficult to install
Comment: I have one positive thing to say about this hood: It makes the camera look pretty cool and professional. Other than that, this thing is a piece of s**t that broke a month or two after I got it. The clip-on mechanism is poorly designed and hard to use even when it's not broken. Why don't they just make it screw-in? I'm not sure if this is the only option for this lens, I haven't looked yet. You have to use a hood so I might be forced to buy another one, but I would stay away from it if at all possible.
Update 4/24/07: I bought a rubber fold-up hood on eBay, and it's infinitely better than the Canon. It screws solidly into the hood adapter, and folds up out of the way when not in use. I highly recommend getting that instead of this garbage.
Customer Rating:
Summary: Not the best fit, but it works
Comment: The adapter screws on to the filter threads, and then the oversized hood snaps (via two plastic squeeze tabs) on to that. Since the lens doesn't zoom there isn't much chance of vinetteing, but it looks a bit akward and because it's so wide I'm not sure how much glare it keeps out.
However, if you (like me) bought this lens for low-light work because of the f-stop, you're also buying this hood for the same reason I did: lens protection (vs lens flare.) Since it's the only one Canon offers currently, it's really your only bet.
Summary: Works great and gives a nice protection from sunlight
Comment: I got this hood for my new EF50mm and it is all I could ask for. It gives a nice look to the lens and camera and protects the lens from direct sunlight.
If you get the EF50mm this Lens Hood is a must have!!
LR
Customer Rating:
Summary: regret getting it
Comment: I think it's too pricey for what you're getting. This is a flimsy plastic hood with a metal ring adapter which screws onto the front of the lens. Canon probably gets both pieces manufactured for pennies. The two pieces awkwardly fit together and it's tricky to get the hood mounted onto the ring. So, 1 star for cool looks and 1 star for trying.
Customer Rating:
Summary: does it matter?
Comment: very awkward hood which by appearance is quite small. not sure if it acutally makes a difference and so far i've left it off the lens. not quick to get on and off.
Customer Rating:
Summary: POS, broke quickly, difficult to install
Comment: I have one positive thing to say about this hood: It makes the camera look pretty cool and professional. Other than that, this thing is a piece of s**t that broke a month or two after I got it. The clip-on mechanism is poorly designed and hard to use even when it's not broken. Why don't they just make it screw-in? I'm not sure if this is the only option for this lens, I haven't looked yet. You have to use a hood so I might be forced to buy another one, but I would stay away from it if at all possible.
Update 4/24/07: I bought a rubber fold-up hood on eBay, and it's infinitely better than the Canon. It screws solidly into the hood adapter, and folds up out of the way when not in use. I highly recommend getting that instead of this garbage.
Customer Rating:
Summary: Not the best fit, but it works
Comment: The adapter screws on to the filter threads, and then the oversized hood snaps (via two plastic squeeze tabs) on to that. Since the lens doesn't zoom there isn't much chance of vinetteing, but it looks a bit akward and because it's so wide I'm not sure how much glare it keeps out.
However, if you (like me) bought this lens for low-light work because of the f-stop, you're also buying this hood for the same reason I did: lens protection (vs lens flare.) Since it's the only one Canon offers currently, it's really your only bet.