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Joanna Trescott
08-06-2008, 05:19 PM
I shot this with Canon 20D, 10-22mm lens at 10 mm. 1/200 sec @ F20, ISO 400. Tripod mounted. I did a little dodge and burning. I am concerned about the tree in the upper lefthand corner -- the horizon is correct, but it looks askew. Any suggestions (besides new tilt lens)?

Robert Amoruso
08-06-2008, 10:07 PM
Joanna,

No I won't tell you to get a Tilt-Shift lens. :)

This appears to be barrel distortion. A problem with wide-angle zooms at their widest setting. You can use Photoshop. Filter > Distort > Lens Correction.
In the menu use REMOVE DISTORTION and I set it for -33 to get the repost below. Note how much of the image is lost. I also had to sharpen it again.

The most popular commercial program for these types of corrections is DxO Optics Pro at http://www.dxo.com/intl/photo/dxo_optics_pro/exclusive_features/overview.

The opposite of barrel distortion is pincushion distortion and is relate to longer focal length zooms.

Try a google search on barrel distortion and you ill find a ton of info and recommendations. I tried Panorama Tools (freeware) and one of its plug-ins CORRECT. Did not like it. Discussion at http://www.creativepro.com/article/photoshop-how-to-eliminate-barrel-distortion-caused-by-camera-lenses on PTools as well as using PS's Transform Tool.

Try Edit > Transform > Warp and pull the top left rectangle to the right to straighten the tree. The key to using the transform tool is trying to make it look natural.

Roman Kurywczak
08-07-2008, 09:24 AM
Hi Joanna,
It's funny you posted this one because I just had the same issue with my Pemaquid light image and I had the same delimma. Robert's re-post definitely corrected the lean and it is the technique I used on my post. The only issue I have, as I did with mine.....is that it removes so much of the canvas.......that I then don't like the crop.....as you lost a great deal of the potholes.
Here's another version and way of trying this. Open the imagre in PS. Grab the crop tool and select the entire image. In the top menu where brush size is........is a perpective box........check it.........grab the upper left corner and pull it out till it looks parallel to the tree. Hit OK. Now you have to crop .....or crop and clone in like I did. (I actually did it twice....going about 1/2 way each time then cloning in).
In the re-post i circled what appears to be a human shadow??? Be careful of this when composing.........but again.......a very nice use of lines and framing elements.
I only did the corrections on the left side..........as you can see the trees on the right are also leaning.......so same method can be used.

Robert Amoruso
08-07-2008, 11:34 AM
Thanks for adding the crop tool method Roman, I forgot that one.

Joanna Trescott
08-07-2008, 03:24 PM
Roman and Robert. I can't wait to try these methods...I should have lots of wide angles to work on. Thank you!

Stephen Stephen
08-08-2008, 11:43 AM
Joanna nice image and Robert and Roman have offered some great advice that I'll likely try as well.