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Old Apr 28, 2008, 12:30 PM   #1
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I've just got a Canon A650IS and when there is a bright light in the picture, I get a strange artifact on the image that is EXACTLY the same shape as the light source, but not at the light source. The result is the same as if there were a scratch or dent on the lens (I've seen this before), but I can't find one on the front lens (maybe on one of the other lenses). I'm thinking it's a manufacturing defect... anyone else got the same thing? I don't think it's normal lens flare because lens flare usually doesn't take on the exact shape of the light source. Any ideas what might be wrong before I try and return it?
(my A630 and A610 did not have these kinds of artifacts, until I scratched the lens of my A630 which is why I got the A650IS in the first place)
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Old Apr 28, 2008, 12:37 PM   #2
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it depends what angle you are to the light source

the best way for people to help you is to post the picture. without that u will only get guesses, and mine is lens flare



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Old Apr 28, 2008, 2:26 PM   #3
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It's probably flare related and you're just seeing some ghosting caused by reflections within the optical elements in the lens.

Here is an article on the subject:

http://www.vanwalree.com/optics/flare.html

This one shows how filters can often be a contributing cause to ghosting and flare issues. Personally, I never use UV filters with digital cameras.

http://www.vanwalree.com/optics/filterflare.html

I've seen far worse examples (usually with UV filters in harsher lighting).

If you're seeing something different, I'd downsize a photo to around 640 pixels wide and post it here for users to comment on. See this thread:

How to post your photos

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Old Apr 28, 2008, 5:48 PM   #4
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(Click to access images on flickr - see descriptions)
http://www.flickr.com/photos/[email protected]/2449568415/

http://www.flickr.com/photos/[email protected]/2450392372/
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Old Apr 29, 2008, 5:20 PM   #5
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I put the links to two sample images in my last post. Anyone have any idea if these are normal lens flare or a fault in the lenses like a small scratch or dent?
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Old Apr 29, 2008, 9:51 PM   #6
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I took a look at the first, and it appears to be normal flare to me. Without the Exif info, I'm not certain, but would guess you aperture was wide open, which is when this will show up if it is going to.

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Old Apr 29, 2008, 10:40 PM   #7
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Aperture was at 3.5... however, I just did a couple test shots in similar light conditions... didn't matter if the aperture was wide open or as closed as it could be... the result was exactly the same both time. And the thing is, why does the A650 do this in conditions that older cameras like the A75, A610, A630 would not? (I've been an owner of all and have taken plenty of night shots, and I saw this as a problem on my first shot with the A650 and its in pretty much every night shot). And the problem I'm refering to is not the glare around the lights, but rather the two dots out in the top right hand of the first shot.
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Old Apr 30, 2008, 1:10 AM   #8
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Yes, the two light spots in the upper right are what I was referring to also. If you have been taking these type shots with your other cameras and not seeing this effect, it may be due to a difference in lens coatings.

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