Lens hood and corner darkness.

[tim11]

Hi folks,
As the thread already suggests, do I have to put up with some corner darkness when using the lens hood; especially when flash is used. Or is that because of the hood is not good?

[nqjudo]

Are you shooting with a 3rd party hood or one from the maker of the lens?

[tim11]

The hood comes with the lens I bought. In this case it's the 18-50. I have to crop some portion out and that sux.

[nqjudo]

HHHmmm. The only time this has ever happened to me is when I didn't have the hood on properly (not twisted all the way).

[talkingdog]

That only happens when I use the pop up flash with the hood. When I don't have an external flash I take off the hood with that lens. Also try bouncing the flash.

[tim11]

I'm sure I always fit in the hood nicely. So the hood doesn't/shouldn't cause the dark corner effect? And it's with the speedlight SB800 when that happen.

[achuang]

This case sounds interesting, because the lens hood casting a shadow from the flash would cause a shadow in the bottom centre of the image. The lens hood causing vignetting should not be any different whether a flash is used and it should be in the corners. The SB800 is far enough away from the lens (compared to the popup) to not be blocked by the lens hood.

What it sounds like to me is that maybe the zoom setting on the speedlight is set at a setting which is not wide enough for the focal length on the 18-50 which you're shooting at so the light from the flash is not reaching the corners of the image.

[nqjudo]

Yeah Tim, is it the hood causing vignetting generally or is it shadowing from the flash?? As a rule I would say that a hood designed for the lens should not cause vignetting but they can and do often cause flash shadows. Do you have any pics??

[Graystar]

The hood comes with the lens I bought. In this case it's the 18-50. I have to crop some portion out and that sux.

At least one review also notes dark corners...

http://www.topicpoint.com/sigma_18-50mm/index.html

Didn't your lens come with a petal hood?

[TeddTucker]

I have the same lens and hood and often experience dark corners also.

[tim11]

Thanks for your interest everyone.

nqjudo: I don't have suitable photos to show just now. Now at least I know this hood has some corner problem. Is that because of the lens design or the hood itself? Is it possible to find a different hood that will not cause dark corner?

[cdifoto]

The dark edges aren't from the hood. They're from not pulling down the wide-angle diffuser, if you're shooting with direct flash.