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Dogger

macrumors member
Original poster
Oct 29, 2006
43
0
Vancouver BC
Anyone ever seen anything like this ?
Only had the camera few weeks and have not shot many images.
I noticed these darkened corners when I shot some images in the snow.
No filter or hood attached, we swapped the lens onto a new body in the store and had no problem, we then swapped a new lens onto my body and got the darkened corners. So we determined it's the body.
This is a shot of the floor in the store.

D80test.jpg
 

Jay42

macrumors 65816
Jul 14, 2005
1,416
588
That looks like vignetting from the lens (darkened corners), I've never heard of a body causing that. Did you try two different copies of the same lens? You may want to try a different lens that you know has low light fall-off. Also, short focal lengths (wide-angle) and smaller apertures are more prone to vignetting, so try shooting something zoomed all the way in, wide open, and see if you get the same problem. I'm a canon guy, so I don't own a D80, maybe someone else knows more.
 

ChrisA

macrumors G5
Jan 5, 2006
12,828
2,033
Redondo Beach, California
tried another nikon 18-70 in the store and got the same results with different focal lengths.

Possibly ALL 18-70 lenses vignette like this. Try using a 50mm lens. the 50 is a full frame lens

You are only getting a 1/2 stop or so fall off. Perhaps this is just the way that lens works. This can be corrected in post processing. This kind of thing is more common then most people think because it does not show in "normal" photos.

Almost all wide angle lenses have some loss of light at the edges. If you think about it, when you shoot a flat wall the part of the well that is near the edge of the frame is farther from the camera. You are seeing the center o the frame at 90 degrees head on and the edge at an angle. -- these geometric effects cause light fall off.

You should do the test with a 50mm or longer prime lens

For people who are ver concerned, thy make "center filters" these are nuetral density filters with greater ensity in the centers and clear edges. These are used for very wide angle shots mostly be people using view cameras. So the problem is common ennough that there is a common way to solve it

Many times I will intentionally darken the edges of a frame in post processing. This works for many subjects
 

Dogger

macrumors member
Original poster
Oct 29, 2006
43
0
Vancouver BC
Thanks for the replies all good info, however the store camera body did not produce the same result even with my lens on it.
This one was shot at 4.5
 

Abstract

macrumors Penryn
Dec 27, 2002
24,869
899
Location Location Location
Possibly ALL 18-70 lenses vignette like this. Try using a 50mm lens. the 50 is a full frame lens

You are only getting a 1/2 stop or so fall off. Perhaps this is just the way that lens works. This can be corrected in post processing. This kind of thing is more common then most people think because it does not show in "normal" photos.

Almost all wide angle lenses have some loss of light at the edges. If you think about it, when you shoot a flat wall the part of the well that is near the edge of the frame is farther from the camera. You are seeing the center o the frame at 90 degrees head on and the edge at an angle. -- these geometric effects cause light fall off.

You should do the test with a 50mm or longer prime lens

For people who are ver concerned, thy make "center filters" these are nuetral density filters with greater ensity in the centers and clear edges. These are used for very wide angle shots mostly be people using view cameras. So the problem is common ennough that there is a common way to solve it

Many times I will intentionally darken the edges of a frame in post processing. This works for many subjects

Very true, but he said he tested the same lens on a different camera, and tested the camera with a different lens.


I want to know what f-stop you used on BOTH cameras. If it's different, then that may be why the results were different on the two cameras. I would also suggest doing the same test outdoors. Doing this test indoors is VERY difficult.

Try going outside on a nice, cloudless day, and try taking a photo of a perfectly blue sky. See any vignetting in the corners? Try the same lens on any other camera body and see if it still does that. I'm sure the store would cooperate. Then, try another lens. If it was the camera itself (highly unlikely), surely it wouldn't matter which focal length you used, so try a longer lens, say a 105 mm macro lens.
 

ChrisA

macrumors G5
Jan 5, 2006
12,828
2,033
Redondo Beach, California
Very true, but he said he tested the same lens on a different camera, and tested the camera with a different lens.

The way I read it, I thought he used different examples of the 18-55 lens. He needs to test with different kinds of lenses and specifically with a longer lens that is known NOT ti vignette. Any prime non-DX format lens that is 50mm or longer would work
 

Abstract

macrumors Penryn
Dec 27, 2002
24,869
899
Location Location Location
Well I thought that he used the 18-70 mm on the Nikon D80, got vignetting, then put the same lens on another D80 body and got no vignetting. Then he tried a different copy of the 18-70 mm that they had in the store, put it on his D80, and he also got vignetting.

That's why he concluded that it must be the cameras, since the same lens doesn't cause vignetting on another D80.

Anyway, like I said, the focal length and f-number should have been the same when doing your testing. I suggested using the 105 mm macro lens because like ChrisA said, it's a prime lens and it should show EXTREMELY low light falloff, especially at f/4 or f/5.6. Since you're saying it's the camera that's causing the vignetting, then if no vignetting is observed in a photo of a perfectly blue sky after using the 105 mm macro, or 85 mm f/1.8, or any other good Nikon prime lens, then the camera isn't a problem. However, if you still see vignetting with one of these primes at f/5.6, then it's the camera, because it's definitely not the lenses.

And besides, if the problem was the camera itself, the vignetting should happen using any lens at any focal length.
 

Bidochon

macrumors newbie
Oct 11, 2006
13
0
Vignetting with the 18-70 is an old story especially at low f-stop, if your picture were made at f3.5 then the vignetting amount can be normal in these shots. try at f-8, normally vignetting happens at wide aperture, especially with dx lenses.
Try with a 50mm at f8 then if you are not sure.
I don't think it is a body issue.
 

Dogger

macrumors member
Original poster
Oct 29, 2006
43
0
Vancouver BC
Thanks for all your suggestions, turns out according to a Nikon tech, underexposing with the lens wide open will cause this light fall off around the corners.
 
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