Warp Transformation
Posted: June 16th, 2013, 9:10 pm
I have an image, taken inside a forest, of a sunrise shining from between some trees. Because of the limited space where I was positioned and the height of the sun, the lens is pointing up a bit, resulting in some fairly obvious "key-stoning" of the trees.
I attempted to correct this distortion by using the Warp Transform and, although mostly successful, I notice the revised image still shows distortion, albeit of a different nature. The trees now "barrel out" where the tops and bottoms are the same distance from the image edges, but the middle portions are closer to the same edges, making it look like the trees are all slightly curved.
To correct the keystone effect, I merely moved the two upper grid points in towards each other. However, there does not seem to be anyway to place new points halfway along the edges to be able to control the middle of the image and prevent the barrelling I described.
Not familiar enough with this transform to know if I should be doing the operation differently or if I need to add another transform to deal with the second effect.
Any advice would be appreciated.
Marv
I attempted to correct this distortion by using the Warp Transform and, although mostly successful, I notice the revised image still shows distortion, albeit of a different nature. The trees now "barrel out" where the tops and bottoms are the same distance from the image edges, but the middle portions are closer to the same edges, making it look like the trees are all slightly curved.
To correct the keystone effect, I merely moved the two upper grid points in towards each other. However, there does not seem to be anyway to place new points halfway along the edges to be able to control the middle of the image and prevent the barrelling I described.
Not familiar enough with this transform to know if I should be doing the operation differently or if I need to add another transform to deal with the second effect.
Any advice would be appreciated.
Marv