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Old Apr 3, 2005, 8:22 PM   #1
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I am having serious problems with "Dust Orbs" appearing in pictures. Mostly indoor pictures. These things are ruining my pictures everywhere I go indoors. Are they caused by the Infrared Beam that the camera uses to focus? Or is something else wrong with my camera? Do ALL digital cameras have this problem with dust? Do DSLR have same problem? How come these dust orbs only appear with Digital Cameras, and not film? I need a digital camera that works indoors. Any help appreciated. Thanks in advance....
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Old Apr 3, 2005, 10:16 PM   #2
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KODAK questions



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Old Apr 3, 2005, 10:42 PM   #3
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These are being caused by your flash reflecting off the dust particles in the air. Only way to completely avoid it is to shoot without flash, but that would probably require a DSLR shooting at a high ISO.
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Old Apr 3, 2005, 11:08 PM   #4
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okay thanks. But why is this more of a problem with digital cameras? I have never seen this before when using p&s film. I have used a lot of p&s film cameras over the years too. None had this problem.
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Old Apr 10, 2005, 9:40 PM   #5
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GoCubs wrote:
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>...clip...
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>"These are being caused by your flash reflecting off the dust particles in the air."
>
>---end clip---

Dust particle reflections ... amazing. I would have never figured that out in one thousand years.

Thanks for the info.

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Old Apr 11, 2005, 1:34 AM   #6
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This looks more like a case of internal reflections of the room lights to me. This occurs at large lens openings (aperture f/2.8 ) when there are bright light sources off center in the image. Look at the geometric relationship of the ceiling lights, and compare to the spots. There are quite a few lens elements in a zoom lens, and coatings are not perfect, so light entering off-angle gets reflected inside the lens.

This is not as prevalent in D-SLRs because of several factors. The lenses generally have lower zoom ratios, which means fewer elements. They are more expensive, in part due to the higher quality coatings used. They also can use higher ISO settings, which enables smaller apertures.

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Old Apr 13, 2005, 4:44 PM   #7
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Seems to me VT hit the nail on the head. Dust reflections, LOL.
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Old Apr 13, 2005, 10:48 PM   #8
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Almost certainly it is the combination of dust and a flash that is close to the lens is the cause. try entering 'photo flash "dust orb"' (w/o single quotes, with double quotes) into Google. Most of the returns talk about ghosts, but you can do your own experiment.

Do some shots in a fairly clean room, then stir up some dust and shoot again. You can generate dust by shaking a pillow, putting the vacumn cleaner on blow and blast away at corners and under tables, invite your uncle Fred in after he has spent the day throwing hay into the mow, ... I think you will find the density of "ghosts" increases with the amount of dust. That might say something about the supernatural, but I think it says more about reflections from small paticles.
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Old Apr 13, 2005, 11:02 PM   #9
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Actually I verified thatit is actually dust particles floating in front of the lens. The dust is being lit up by the flash.

I layed a pillow on the floor, and hit it a few times. I then made my camera level to the pillow, and took pictures with flash. All flash pictures had these spots in them. I thenused my old 35mm Canon Owl P&S camera and took flash pictures. None of the developed pictures had any dust spots.

Why don't 35mm P&S have these dust spot problems? I will have to go try some more digital cameras and see if they have the same problem as this Kodak. May I request that Steve do some testing of this himself and put results in each camerareview?
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Old Apr 14, 2005, 8:02 AM   #10
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wile_e wrote:
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... Why don't 35mm P&S have these dust spot problems? ...
I suspect that in addition to the lens-flash distance, the physical focal length (not 35mm equiv) comes into play as well. If you have a very short lens for your chemical camera that is the same physical focal length as your digicam it might be possible to test that idea.
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