This this week in Imagecraft Bootcamp we’re covering keystoning, also known as the tombstone effect or keystone effect,
The keystone effect, also known as the tombstone effect, is caused by attempting to project an image onto a surface at an angle, as with a projector not quite centered onto the screen it is projecting on. It is a distortion of the image dimensions, such as making a square look like a trapezoid, the shape of an architectural keystone, hence the name of the feature. In the typical case of a projector sitting on a table, and looking upwards to the screen, the image is larger at the top than on the bottom. Some areas of the screen may not be focused correctly as the projector lens is focused at the average distance only.
This is the final image, still a little wonky, but If I straighten the top part of the building I loose the horizon line and the bottom of the building. For the most part, I am happy with this image now.
First I used the Lens Correction as Mitch suggested, I tried, Auto, Vertical, Horizontal and Full, but I honestly I didn’t like what it did with any option, so I turned it off.
I tend to use the Lens Profile tab (same area) and I have set up all my lenses in this……it tends to calibrate better. I then went to Manual and tweaked a little further. I do not think I will get it much better than this.
I then went to the Crop & Straighten tool and tweaked the image until I was mostly happy; Horizon line straight and the bottom of the building where it meets the ground is most straight vertically as well.
I then adjusted the exposure, tweaked a few things as well and voila……there you have it.
OK So not a huge amount of difference, but it’s a start 🙂 I perhaps need to work with the manual setting and fiddle a bit more