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Old Aug 14, 2003, 12:43 AM   #1
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Default What went wrong here?

I would like some comments on this picture. It has a lot of chromatic abberation / blooming in it. As EricS already pointed out, it is only around certain edges of the white objects in the picture. It was taken with the canon 75-300 USM III lens. Is this normal for this lens, or is something going on?

The full sized image is at : http://www.pbase.com/image/18796286/original

Thanks for any comments!

Barthold

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Old Aug 14, 2003, 3:51 AM   #2
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Could it be that it's everywhere, but the white areas just show it more because of how all the different wavelenghts add up? :lol: :lol: :lol:

... and what APO elements are designed for!
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Old Aug 14, 2003, 10:52 AM   #3
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Another thing to note is that it seems to be mostly on the "top" of the things which are white. Look at the text on the side of the car. The bottom of the letters don't have it, but the top do.

I'm rather ignorant here, but is that normal for this problem (not all over, but on one side of an object?) And exactly what is this effect? CA? I want to learn so I use the right terms in the future.

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Old Aug 14, 2003, 12:07 PM   #4
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Eric, NHL,

Same here, I want to learn, and know if this is normal for this lens. If so, it pretty much sucks :-)

Barthold
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Old Aug 14, 2003, 3:34 PM   #5
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Hi,

Sorry but I had the same on my lens without the USM, this was the reason to buy a Sigma APO lens.

Greetings,
Frank
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Old Aug 14, 2003, 5:02 PM   #6
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You got me there as to why it only affects the top part. Could it be the angle of the light illuminating the scene?... EE background here with no optic experience; However if you guys want to talk DWDM, OC3-192, SONET or Optical Networks I'm all ear! :lol:

Is this just me? but this lens also shows lack of contrast as well...
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Old Aug 14, 2003, 6:36 PM   #7
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I see this as lens flare caused by the bright white next to a very dark area. Notice that it exists mostly were white boarders black.
The angle of the reflected white areas is governing the amount of flare and the location. Notice that on some of the other pictures the flare is much less especially were the contrasting colors are not so extreme.
Being a Zoom lens with all of its glass elements it would naturally be more likely have some flare in a situation like this.
I don't think you have a bad lens but a lens with certain limits which you have discovered.

Ted
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Old Aug 14, 2003, 7:48 PM   #8
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IMO it's not flare. Flare is usually strongest at one point diminishing as it spread out: http://jonathanclark.com/diary/flare/. The problem is even throughout the picture...It's not blooming either since blooming occurs with the CCD/sensor, the 10D does not have this and obviously the problem goes away with the lens...

Two down ?
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Old Aug 14, 2003, 8:22 PM   #9
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So are be back to Chromatic Aboration?

I wonder if there is a site which has examples of all these effects?

Eric
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Old Aug 14, 2003, 8:25 PM   #10
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Yeah if there is, I would like to know as well... Just so I know wtf you guys are talking about... :lol: Nah, I mean I would just like to see examples of what exactly to look for. Ive seen the ones with like interfence lines running through objects or blackness, and then ive seen this. I would just like to see examples of errors/undesired effects of digital photography.
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