AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |
Back to Blog
Panorama stitcher adjust for parallax2/19/2023 Cases studies Far straight object (Case 1)Ī straight object that's sufficiently far away from the camera can be long enough to encompass a large angle range when it's viewed from the entrance pupil location. The distance of the object from the camera is of outmost importance as any experienced panographer has verified that these problems are gone or substantially reduced when the subject is sufficiently distant from the camera (say more than two or three meters and the more the better). This has a detrimental effect for the correctness of the stitching of two images but this can also affect the appearance of a single image. I have made some measurements to assess the relation. In between these two extrema, the entrance pupil falls somewhere between them.the object is right on the longitudinal axis of the lens) the entrance pupil is about two centimeters behind the previous position. the object is located at a right angle from the lens shooting direction) the entrance pupil is located behind but very close to the front glass surface of the lens. When this angle is about 90 degrees (i.e.Let's recall that the position of the entrance pupil of a fisheye lens varies in accordance with the angle between the line of sight which the object of interest is seen and the optical longitudinal axis of the fisheye lens: When the seam (between two of the images to be stitched) sweeps a large range of angle of view from which the object space is seen, there may be subsequent stitching errors. Nevertheless, that special care cannot solve totally the problem of parallax errors or it does not in all occasions. This prescription is well known and is found on many good pages on the web. It is advisable to adjust correctly the position of the entrance pupil (aka nodal point and NPP = no-parallax point) to reduce the effect of parallax errors when stitching overlapping images. They are not directly related to gear set-up error, stitching tools misusage while these could magnified greatly the negative effect.Īnd after having found the root cause, I have elected to write this article to share my findings. Some straight edges or straight objects shot at very close distance and on a single image would appear unduly bowed when viewed in a rectilinear projection.Īfter verification that the origin of this problems had no connection with my (lack of) skill, I have investigated in order to pin down the real source.There was also very bad Control Point concordance on some seams. Need of heavy and lengthy post-processing because of stitching errors (sometimes huge).In the course of making them, I have stumbled on two difficulties that have made the production of the output panorama very problematic on some occasions: You may look at some of my spherical panoramas shot at VERY close range to the subject. Summary: When pano-macro-graphying with a fisheye, the output defished image of a straight line in real world. Parallax effect on a single fisheye image Fisheye Lens "Parallax effects" on a single image? Subject
0 Comments
Read More
Leave a Reply. |