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Old Aug 31, 2004, 4:34 PM   #1
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I took this shot this evening on my 300d and 18-55 efs lens. I was quite happy with it apart from the slightly washed out sky but the worst thing is the bending horizon. Ive read a little about barrel and pinch distortion but still dont understand it fully. Why does it happen? Is it the camera or lens? Can i stop it happening again? Can i fix it using PS7?
Any help would be gratefully appreciated.
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Old Aug 31, 2004, 5:18 PM   #2
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It is the lens, and you can indeed fix it with PS7 with careful and subtle application of the Pinch/Spherize filteror the "Distort" Transformation tool.

I'll take your image and see what I can accomplish with it later on tonight when I get home.
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Old Aug 31, 2004, 5:47 PM   #3
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There is a forum a little way down called Extreme ?Makeovers. Post it there and you'll get lots of people attempting to fix it and showing you how they did it. Monza just started a thread about this sort of thing to.
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Old Aug 31, 2004, 6:30 PM   #4
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At that focal length, with that lens the only way to fix it "in camera" is to put the horizon line right through the centre (boring) so software is your only hope.

Ira


Here is a "quick and Dirty" Paintshop fix, used pinch to fix the distortion and then did a very quick redraw od the horizon. I deleted the picture from my computer as soon as it was completed. This was just a 20 minute job to show how it could be done, it would take some practice to get it right.


If you have already viewed this image click refresh on your browser to see the final version.
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Old Aug 31, 2004, 11:22 PM   #5
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Monza's result is near identical to the result that I acheived.
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Old Aug 31, 2004, 11:39 PM   #6
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ok, monza pretty much told why it happened, but i'll go into more detail (at least wat i know about it )

because the shot was taken in wide angle, the lens causes a fisheye effect...not as drastic as the fisheye though, because (correct me if i'm wrong..cuz it's possible) the the lens "bends" the image, so that you fit more of the scene in, in one shot,

to fix it....and get the same composition, you'd need to take at least a couple steps backward, and probably float a couple feet in the air, and zoom a bit....that evens out the "bend" effect...but it will also "compress" the depth...which you probably won't want...

ok..hope this helps, and doesn't just confuse you..

lol

Vito
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Old Sep 1, 2004, 5:13 AM   #7
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Thanks alot guys, you've really helped. I've posted it in 'exteme makeovers' so l'll see what everyone else can do.
Thanks
mealers
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Old Sep 7, 2004, 12:28 PM   #8
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Iv'e just found this great little plug in for Photoshop. Just though i would share.
http://www.dpreview.com/learn/?/Imag...rection_01.htm
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