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red99td5
12-10-2010, 11:23pm
Hi guys,
I recently took a series of 27 photos to form a hdr panorama of the grand tetons in the states. Unfortuanetly despite my best efforts some of the shots are not level. (perhaps the fact it was -20'c had something to do with this) I know how to use the ruler etc to fix this but wanted to ask a question. I took this series of photos sitting on the edge of a lake and you can clearly see the opposite side of the lake. So do i run the ruler along the opposite shoreline, or as the lake isn't huge will the roundness of the shoreline effect the leveling? Does that make sense?

Aaron

ricktas
13-10-2010, 6:24am
A few other factors come into play here. The most prominent being your lens. Not only could your horizon be crooked, but it could also be curved. Curvature of the horizon is caused by wide angle lenses and is a distortion prevelant in WA lenses. So you could need to both level the horizon and correct any distortion as well.

I use the ruler tool that you alluded to, I zoom in and look for something that I know is level (you can also use something that is known to be vertical). I then draw my ruler line, go to Image > Image Rotation > Arbitrary. Sometimes due to the elements of the photo it is hard to find a true vertical or horizontal, but you can only do the very best you can.

Distortion is corrected in the Filters Menu, Filters > Distort > Lens Correction.

Some camera's have the ability to display a grid in the viewfinder that allow you to get as level as possible at the time of shooting. Others have a 'level' built in. Some tripods have a small spirit level also. Use all the tools available to you to ensure your camera is as level as possible before taking the shot.

ZedEx
13-10-2010, 8:03am
I'm wondering if photoshop would correct this for you, when it goes to auto align the pano? Of if it would crop weird. Maybe just line them up roughly and see how it goes. The auto align function will do just that - align each layer, so as long as they're pretty much close then that should do. You can rotate the finished panorama after processing then

red99td5
13-10-2010, 11:58am
Thanks guys,
Thanks for your input.
This is one of the many attempts I have done of the photo
http://www.flickr.com/photos/25469702@N08/3576387063/in/set-72157618769158574/

Thanks for the tip Rick, yes i corrected for lens curvature and also shot at ~35mm from memory to try and avoid too many issues. The tripod had a bubble level and was set up level, it was more the fact i was standing amongst boulders and using a brand new ball head which i wasn't so comfortable with that led to a few issues. Also the sun was rising fast and i was trying to minimise the increasing light levels whilst taking 27 shots.

So my question was really about whether the opposite lake shore could be used to straighten each of the images or not. As you can see in the above image the dead pinetree on the very left isn't vertical for example.

Also in regards to workflow I have tried the following, how does it compare to everyone elses. Method 1, open all 27 images in camera raw, globally correct white balance, straighten each image, open in cs5,remove dust bunnies, then merge to pano.
Method 2 as above but then export as psd, then use autopano pro
Method 3 as above in method 1, but after cleaning merge each set as hdr in cs5 then merge to pano.

Aaron

ricktas
13-10-2010, 12:28pm
you can end up with optical illusions cause by a 3D world, being represented in 2D, where the shoreline is not an equal distance from the lens, across the photo. Just make the horizon level (as it should be), and forget about shorelines that jutt in and out.

OzzieTraveller
14-10-2010, 9:35am
Hey Ricki

I end up with "optical delusions caused by a 3D world, being represented in 2D" every day :cool: :cool:

Regards, Phil