> Pentax D-FA50 f/1.4: comment from PF : "Most 50mm lenses don't have significant issues with geometric distortion, and the HD Pentax-D FA* 50mm F1. stable panoramic video stitching from unstructured camera array input. Traditionally, in order to construct a panoramic image including multiple faces of an object, consecutive video frames must be captured around the object so that. Parallax and object motion present challenges to image registration, leading to. In contrast, the method proposed in this work produces an unwrapped surface image of a three-dimensional spherical object. comment from PF 50mm lens comparison: "We are happy to report that none of the Pentax 50mm lenses had any measurable distortion." Conventional panorama techniques create a wide-angle image by stitching images taken from the same viewpoint. Some example images after warping are given below. So it should be clear that in order to avoid parallax, it is important to take all images from the same viewpoint. We can project the image to a cylinder surface at the beginning of stitching, by the following formula: where is the focal length of the camera, and is the center of image. Explanation of No-Parallax or Nodal Point: Even if your setup is. Unlike other artefacts like barrel distortion, correcting for parallax errors is impossible the best one can do is attempting to mask the misalignments by retouching the stitched panorama afterwards. focal length setting Distortion introduced by imperfect lenses Parallax (camera not. best choice when it comes to stitching individual images together with objects close up. comment from PF review "This lens is designed as a macro lens with a flat field of focus and no distortion and we were definitely not able to detect any distortion." The panoramic images used in this article were made by James Rigg. > Pentax D-FA70-200 f/2.8: 0.9% at 70mm, -0.6% 135mm, -0.5% 200mm problem with the DFA70-200 is the nodal point moves a lot from near front of the lens at 200mm to back of the camera at 70mm, very sensitive to the focal length and a pain to adjust in the field. For panoramas taken without a panoramic head, parallax error may. You may have to do a light meter reading for the brightest and darkest parts of your. ephotozine test: "70mm gives +1.45% pincushion distortion" Expose for your scene manually and dont change the exposure between shots. With the idea of reproducing a 4x5 exposure area by stitching multiple exposures from a Pentax K1, the "crop" factor between 4x5 and full frame being about 3x, for a wide angle shot I'd need to use a focal length of 100mm (more or less depending on the final FoV of the stitched composition). Going into Pentax forum in depth lens review or ephotozine test results, we can compare lenses on how much optical distorsion they produce. Along with parallax errors, non-ideal lens distorsion is a pain for stitching images since not all distorsion follow a nice a,b,c distorsion correction model, resulting in some mismatch between frames.
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