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View Full Version : cause of this flare?


J.T.
Oct-14-2009, 02:45 PM
I recently took some shots of the SF Bay Bridge and got this flare from some shots.

Is it caused from cheaper glass, not using a lens hood, combination of the aperture and zoom, or something else?

Thanks for viewing and answering.

Photo was shot at iso 100, with a 50-135 f/2.8 lens at 68mm for 3 sec.
I cannot remember if I had the lens hood on or not or if I was using my circular polarizer. Another shot was shot at iso 100, , same Tokina lens, 135mm at about 4 seconds.

Some other shots also turned out with this similar flare.

craig_d
Oct-14-2009, 03:32 PM
With long low-light exposures, anything that can create reflections inside the lens, will. In daylight, these reflections wouldn't be visible, but at night, with a long exposure, against a dark background, they are emphasized.

In this case, I don't think a lens hood would have helped, because the bridge lights that are reflecting up into the sky are within the frame. This isn't light coming in at some oblique angle; it's part of the image, so a hood wouldn't have blocked it.

If you had a filter on the lens, that could be the problem, especially if it's not multi-coated.

I once took some indoor martial arts pictures using a 1990s Tokina lens (pre-digital, in other words) with a cheap Tiffen UV filter on it. The lighting in the room was dismal, and whenever a fluorescent tube was in the frame, I got horrible reflections similar to what you've got here. I'm not sure whether the lens alone, without the filter, would have done better, but I think it probably would have. Whether that would have merely reduced the problem rather than eliminating it, I don't know.

Your Tokina lens looks to be a lot newer than my old one, if it's the model that Tokina currently lists on their website (AT-X 535 PRO DX f/2.8). The description says it has a "water-repellent" coating, but says nothing about anti-reflective coatings for digital cameras. This surprises me, because it's a DX lens, and therefore a modern lens designed for digital cameras.

My guess is that you had a filter on and that's the main cause of the reflections. Can you try again without a filter and see if that helps?

J.T.
Oct-17-2009, 10:10 AM
With long low-light exposures, anything that can create reflections inside the lens, will. In daylight, these reflections wouldn't be visible, but at night, with a long exposure, against a dark background, they are emphasized.

In this case, I don't think a lens hood would have helped, because the bridge lights that are reflecting up into the sky are within the frame. This isn't light coming in at some oblique angle; it's part of the image, so a hood wouldn't have blocked it.

If you had a filter on the lens, that could be the problem, especially if it's not multi-coated.

I once took some indoor martial arts pictures using a 1990s Tokina lens (pre-digital, in other words) with a cheap Tiffen UV filter on it. The lighting in the room was dismal, and whenever a fluorescent tube was in the frame, I got horrible reflections similar to what you've got here. I'm not sure whether the lens alone, without the filter, would have done better, but I think it probably would have. Whether that would have merely reduced the problem rather than eliminating it, I don't know.

Your Tokina lens looks to be a lot newer than my old one, if it's the model that Tokina currently lists on their website (AT-X 535 PRO DX f/2.8). The description says it has a "water-repellent" coating, but says nothing about anti-reflective coatings for digital cameras. This surprises me, because it's a DX lens, and therefore a modern lens designed for digital cameras.

My guess is that you had a filter on and that's the main cause of the reflections. Can you try again without a filter and see if that helps?

Thanks for your comments and suggestions. I may try to go back sometime and re-shoot the location. It could be the cheap UV filter I had on the newer Tokina lens. Thanks again.

Tim Kamppinen
Oct-17-2009, 01:26 PM
My money is on the filter causing the problem. Judging by the flare on the lights themselves, you don't seem to have been shooting at 2.8, but stopped down a bit, which usually means that crazy flare like this doesn't occur. I could be wrong, but in any case it's best not to use any filters when shooting into light sources, unless they're necessary for the effect you're trying to achieve. It's just one more layer of glass to cause problems.

J.T.
Oct-19-2009, 09:22 AM
My money is on the filter causing the problem. Judging by the flare on the lights themselves, you don't seem to have been shooting at 2.8, but stopped down a bit, which usually means that crazy flare like this doesn't occur. I could be wrong, but in any case it's best not to use any filters when shooting into light sources, unless they're necessary for the effect you're trying to achieve. It's just one more layer of glass to cause problems.

Thanks for the advice, will try that next time.