Re: Can't do perspective correction
- Hi Leonard,
Leonard Evens wrote:
> I am using hugin 0.7.0 under Fedora Linux 9.Time to switch to the latest (pre-) release:
in your case <http://wiki.panotools.org/Hugin_Compiling_Fedora>
> I want to correct horizontal perspective on an image. I followed theRectilinear output should work. The tutorial defines three vertical
> instructions in the hugin tutorial at
> But it doesn't work and nothing I try works. I picked three horizontal
> lines at the top middle and bottom of the building. I get curved lines
> in the preview even though I've chosen rectilinear. I've tried all the
> possible options.
lines (shown as a blue, green and red pair). Poles for road signs can
often be used for those, also the edge of a building from the roof to
the ground level.
You seem to have used several horizontal lines. Only set those on the
actual horizon! They are useful e.g. to level a wavy horizon when you
shoot a panorama from a beach.
> I've attached the image file.You should upload that to your webspace (or something like flickr.com)
and post the URL here.
> Actually I know quite a lot about it4" x 5" (about 100 x 125 mm) with a 75 mm lens lead to a fov of roughly
> The picture was taken with a 4 x 5 view camera with a 75 mm lens with
> minimum distortion. I used a panoramic head and swung to the left 15
> degrees (yaw -15). I used a rise which translates into a vertical
> displacement of about 229 pixels. Is there some way to incorporate
> that information to produce the result I want?
67 degrees (short side) and 79 degrees (long side).
You should carefully optimize for shift (distance of image center from
the optical axis, 'e' = vertical and 'd' = horizontal) and shear (often
introduced by scanners, 't' = vertical and 'g' = horizontal, values in
pixels). Don't optimize all of them at once...
> This image is one half of a two image panaorama with the other halfHugin can correct correct all of that in the same project. Just add your
> turned 15 degrees to the right. I did manage to use hugin to merge
> these after some effort, but the resulting image still needed some
> horizontal perpective correction.
vertical lines and optimize not only yaw, pitch , roll and fov, but also
d/e and g/t as described above.
Hope that helps,