Lens hood confusion?

Question

I have a canon 28-200mm f/3.5-5.6 for my rebel xti and I was looking to buy the lens hood for it, which supplied by canon is the EW-78D. However, I would like to avoid paying the premium that canon charges (like 40 bucks) for this 3 ounce petal-shaped piece of plastic and buy a generic one instead. I haven't been able to find a reasonably priced generic version but have come across the EW-78B II which is designed to fit the canon 28-135mm IS. Now the question: Does the 78 in the model name signify that this hood is 78mm in diameter, and if so will it fit my 28-200? The 78B does appear to be slightly longer than the 78D and I am wondering if that is the only difference.

Answer 1

The 78 has nothing to do with the lens/filter size, as the 28-200mm has a 72mm front thread.

The Canon 28-135mm has a a 72mm front element, as well.  

Chances are, the lenshoods are mountable on either lens, but the EW-78D, because of it's extra length, will provide better coverage from 135-200mm.

Your best bet is to go to a local camera shop and try the hood on there.