lens hood

[bjfowle]

I'm looking at buying a lens hood and have found several rubber ones on ebay, is there any reason not to buy one of these?

 

[SLOShooter]

Just make sure that it's the right size.

 

[Kent Frost]

The only time you don't want to use a lens hood is if your camera has a built-in flash. It could black out the bottom half of the pic. Otherwise, there's no reason not to have one....they only help.

 

[Big Mike]

A solid lens hood will protect the front element if you ram/drop the camera into something flat...like a wall or the ground. The rubber ones will not.

I own a couple of the rubber ones because I like that collapse and can be stored in a tighter space than a solid hood.

 

[Unimaxium]

A rubber lens hood (which is usually or always circular as far as I know) is the least effective shape for blocking out nonimageforming light, since the actual image frame is rectangular. A better shape lens hood would be a "tulip" shape or (the best, but least convenient to carry around) a rectangular shape. For lots of information on lens hoods, check out this link:
http://www.vanwalree.com/optics/lenshood.html