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Old Jul 26, 2004, 10:59 AM   #1
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here some photos of my canon a75.Could you look at them?

and I have somequestion,

1)in some photos there are some circular dusts .Does anyone knows what is the reason?

2) when i want to take a photo that sun light is coming from background the photos are somehow dark.Is there anything that I can do?

Thnak you very much
http://www.ug.bcc.bilkent.edu.tr/~zsahin/fotos.zip
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Old Jul 26, 2004, 11:53 AM   #2
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haldizen wrote:
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1)in some photos there are some circular dusts .Does anyone knows what is the reason?

2) when i want to take a photo that sun light is coming from background the photos are somehow dark.Is there anything that I can do?
1) I don't see it :?

2) It's normal since you probably use general average exposure metering I guess. Youshould use spot metering in those cases ( see your camera manual for how to do it)
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Old Jul 26, 2004, 12:00 PM   #3
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here is the foto.http://www.ug.bcc.bilkent.edu.tr/~zsahin/IMG_0919.JPG
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Old Jul 26, 2004, 2:17 PM   #4
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Looks like lens flare, caused when light hits the lens at a certain angle. An example:

http://www.gamedev.net/reference/art...-tut-shot1.jpg
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Old Jul 26, 2004, 2:29 PM   #5
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It's dust. You only see it in two photos -- both were using flash. Sometimes when you have tiny particles of dust floating in the air, you get these types of spots with flash.


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Old Jul 26, 2004, 2:42 PM   #6
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The circle in the photo from your second post is lens flare. If you look at the chandelier in the background you will see where the light that is causing the flare comes from. Not much you can do other than move a little so a sunbeam from the chandelier isn't directly hitting the camera.

For backlighted portraits where the subject is within flash range I prefer to use fill flash. For things outside flash range spot mode works best for me, but you can also increase the EV if you prefer. With either spot mode or increased EV the bright background will get burned out to a degree. The only way you can get both the backlighted subject and bright background is with fill flash.
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Old Jul 26, 2004, 2:58 PM   #7
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Well, I respectfully disagree guys(unless we're looking at different spots). :-)

You can also see another spot near the subjects right knee. Also, he was using flash.

You see a lot more dust spots in this photo from his .zip file (look near the top of the photo):


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Old Jul 26, 2004, 4:36 PM   #8
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Yep, that is dust.

Several years ago, I got into a heated discussion with several friends who believed that such things were supernatural plasma orbs. :roll:

Here is a corroborating web site.

http://www.dcccs.org/blanke4.htm
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Old Jul 26, 2004, 6:41 PM   #9
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I get those spots on at least 50% of my photos when the flash is used. It's driving me f**king crazy but Canon says there's nothingthey can do about ut...



I have seen it on pictures taken with my friends cameras too, but it doesn't happen very often for them. For them it's like less than 1% of the time... Anyway, I'm sick and tired of it, so I'm going to throw away my crappy A70 and buy something else.
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Old Jul 26, 2004, 6:55 PM   #10
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Nick:

I doubt that his camera works any better than yours. It's only reflections from dust particles. I rarely see 'em, but they're fairly easy to recognize. It's probably because you have more dust particles floating in the air where you are taking flash photos.


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